BACKGROUND
Antennas are typically tested before being put to use. Testing of an antenna is important
for providing accurate measurements of the performance parameters of that antenna. It is very
common and frequent that antennas do not perform as desired or as theoretically expected. As
such, the antenna testing comes into play to measure or assess the actual performance metrics or parameters of antennas before using in the field.
[0002] For phased antenna arrays, performance parameters are typically measured over the
operational bandwidth and temperature. Measuring the performance parameters involves overthe-
air testing, typically done in the far field. Traditional antenna metrology requires expensive,
large test stations - for example far-field anechoic chambers or compact range. The traditional
approaches for performing factory acceptance testing are adequate in low-volume markets (e.g.
fire-control fighter jet .m&ar phased arrays) but are completely inadequate in high-volurne
markets (e.g. 5 6 base station phased arrays) or moderate-volurne markets (e.g. airborne satcom
phased arrays). In particular, most traditional testing techniques are expensive, require relatively
large testing space, and may not be adequate to perform some performance measurements.
[0003] Anechoic chambers, which are commonly used in testing phased antenna arrays and
other antennas can be costly. The cost usually increases with size of the chamber. Also, most
testing equipment can be costly and difficult to control or monitor. Such difficulty can make the
testing process slow, therefore, adding more to the total cost.
SUMMARY
LO0041 In one aspect, embodiments of the inventive concepts disclosed herein are directed to a
method of testing phased antenna arrays. The method can include positioning a phased antenna
array and a probe antenna at relative positions with respect to each other. The phased antenna
array can include a plurality of antenna elements. Either the phased antenna array can act as a
transmitting antenna and thc probe antenna can act as a receiving antenna, or the probe antenna
can act as the transmitting antenna and the phased antenna array can act as the receiving antenna.
The method can include causing the transmitting antenna to radiate a plurality of electromagnetic
waves sequentially. The method can include causing the phased antenna array to operate, during
transmission of each electromagnetic wave of the plurality of electromagnetic waves, according
to a corresponding configuration scheme. The corresponding configuration scheme can define a
respective set of antenna ele~nentsth at are active during the transmission of the electromagnetic
wave or a respective phasc coding scheme applied to the plurality of antenna elements during the
transmission of the electromagnetic wave. The method can include receiving, by the receiving
antenna, responsive to each radiated electromagnetic wave, a corresponding receive radio
frequency (RF) signal. The method can include determining, for each antenna element of the
plurality of antenna elements, corresponding amplitude and phase parameters using the receive
RF signals. The method can include determining one or more performance parameters of the
phased antenna array using the determined amplitude and phase parameters for the plurality of
antenna elements.
[0005] In a further aspect, the antenna subarrays can include a group of antenna subarrays with
corresponding antenna elements having a respective size and supporting a respective frequency
subband. The antenna subarrays can include another group of antenna subarrays with
corresponding antenna elements having a different size and supporting a different frequency
subband.
[0006] In a further aspect, the method can include positioning the probe antenna at a near field
location relative to the phased antenna array. The one or more performance parameters can
include co-polarized anten1l.d gtrin, cross-polarized antenna gain, co-polarized antenna directivity,
cross-polarized antenna directivity, antenna beam width, radiated power, cross-polarization
discrimination, antenna gain-to-noise-temperature, error vector magnitude, adjacent channel
power ratio, pulse quality, one or more side lobe levels, signal-to-noise ratio (SNR), or a
co~nbinationth ereof.
Atty. Dkt. No: 18CR047 (047141-13 11)
[0007] In a further aspect, the method can include determining a far field response of the
phased antenna array using the determined amplitude and phase parameters for each of the
plurality of antenna elements. In a further aspect, causing the phased antenna array to operate
according to a corresponding configuration scheme can include activating the plurality of
antenna elements one at a time. Each antenna element can be activated to transmit an
electromagnetic wave of the plurality of electromagnetic waves and the probe antenna can
receive, responsive to transmission of the electromagnetic wave by the antenna elemenf the
corresponding receive RF signal. Each antenna element can be activated to receive, responsive to
transmission of an electromagnetic wave of the plurality of electromagnetic waves by the probe
antenna, the corresponding receive RF signal. The method can further comprise determining, for
each antenna element of the plurality of antenna elements, the corresponding amplitude and
phase parameters using the corresponding receive RF signal received during activation of the
antenna element
[00081 In a further ,,mpeol*eaa5ing the phased antenna array to operate according to a
co~~espondincogn figuration scheme can include phase steering the plurality of antenna elements,
during transmission of each electromagnetic wave of the plurality of electromagnetic waves,
according to a respective phase coding scheme. Each phase coding scheme can define a
corresponding set of phase shifts or a corresponding set of time delays applied to the plurality of
antenna elements during transmission of a corresponding electromagnetic wave of the plurality
of electromagnetic waves. The method can further comprise transmitting each electromagnetic
wave of the plurality of electromagnetic waves by the plurality of antenna elements phase steered
according to the corresponding set of phase shifts or the corresponding set of time delays. The
antenna probe can receive, responsive to transmission of the electromagnetic wave by the
plurality of antenna elements, the corresponding receive RF signal. The method may comprise
transmitting each electromagnetic wave of the plurality of electromagnetic waves by the probe
antenna and the phased antenna array can receive, responsive to transmission of the
electromagnetic wave by the antenna probe, the corresponding receive RF signal.
Atty. Dkt.No: 18CR047 (047141-1311)
100091 In a further aspect, causing the phased antenna array to operate according to a
corresponding configuration scheme can include phase steering a group of active antenna
elements of the plurality of antenna elements, during transmission of each electromagnetic wave
or the plurality of electromagnetic waves, according to a respective phase coding scheme.
[0010] 111 a further aspect, the method can further include modifying the relative positions by
causing the antenna probe or the phased antenna array to move along a predefined path during
tra~~s~nissoiof nth e plurality of electromagnetic waves.
[0011] In a further aspect, the method can include positioning at least two antenna probes with
distinct polarizations, or positioning a single dual polarized antenna probe. In a further aspect,
the method can include positioning a plurality of probe antennas operating at different center
frequencies at various positions relative to the phased antenna array.
[0012] In a further aspect, the method can include applying a predefined phase offset to the
plurality of antenna elements, and receiving one or more additional receive signals at an angle
offset with respect to a main lobe of the receiving antenna
[00131 In one aspect, embodiments ofthe inventive concepts disclosed herein are directed to a
method of testing phased antenna arrays. The method can include positioning a phased antenna
array including a plurality of antenna elements and a probe antenna at relative positions with
respect to each other. Either the phased antenna array can act as a transmitting antenna and the
probe antenna can act as a receiving antenna, or the probe antenna can act as the transmitting
antenna and the phased antenna array can act as the receiving antenna. The method can include
applying, to each antenna element of the plurality of antenna elements, a corresponding phase
shift or a corresponding time delay to compensate for differences in signal propagation times
between the probe antenna and each of the plurality of antenna elements. The method can
include causing the transmitting antenna to radiate an electromagnetic wave. The method can
include receiving, by the receiving antenna, a receive radio frequency (RF) signal responsive to
radiating the electromagnetic wave. The method can include determining one or more
performance parameters of the phased antenna array using the receive RI: signal.
Atty. Dkt. No: 18CR047 (047141-131 1)
[0014J In a further aspect, the method can include positioning the probe antenna at a near field
location relative to the phased antenna array. In a further aspect, the one or more performance
parameters can include co-polarized antenna gain, cross-polarized antenna gain. co-polarized
antenna directivity, cross-polarized antenna directivity, antenna beamwidth, radiated power,
cross-polarization discrimination, antenna gai11-to-noise-temperature, error vector magnitude,
adjacent channel power ratio, pulse quality, one or more side lobe levels, and signal-to-noise
ratio (SNR).
[0015] In a further aspect, the method can include positioning at least two antelina probes with
distinct polarizations, or positioning a single dual polarized antenna probe. In a further aspect,
the method can include positioning a plurality of probe antennas operating at different center
frequencies at one or more positions relative to the phased antenna array.
[OO16] In one aspect, embodiments of the inventive concepts disclosed herein are directed to a
system for testing phased antenna arrays. The systein can include a signal generator circuit
communicatively coupled to a phased antenna array including a plurality of antenna elements or
a probe antenna positioned at a relative position with respect to the phased antenna array. The
signal generator circuit call generate one or more transmit radio frequency (RF) signals for
transmission by the phased antenna array or the probe antenna. Either the phased antenna array
can act as a transmitting antenna and the antenna probe can act as a receiving antenna, or the
antenna probe call act as the transmitting antenna and the phased antenna array can act as the
receiving antenna. The system can include a processor communicatively coupled to the signal
generator circuit, the phased antenna array, and the probe antenna. The processor can cause the
transmitting antennarro.sequkntially radiate a plurality of electromagnetic waves associated with
the one or more transmit RIz signals. The processor can cause the phased antenna array to
operate, during transmission of each electromagnetic wave of the plurality of electromagnetic
waves, according to a corresponding configuration scheme. The corresponding configuration
scheme can define a respective set of antenna elements that are active during the transmission of
the electromagnetic wave or a respective phase coding scheme applied to the plurality of antenna
elements during the transmission of the electromagnetic wave. The processor can obtain; from
the receiving antenna, responsive to each radiated electromagnetic wave, a corresponding receive
RF signal, the receive RF signal received by the receiving antenna responsive to the radiated
electromagnetic wave. The processor can determine. for each antelma element of the plurality of
antenna elements, corresponding amplitude and phase parameters using the receive RF signals.
The processor can determine one or more performance parameters of the phased antenna array
using the determined amplitude and phase parameters for the plurality of antenna elements.
[0017] In a further aspect, the processor can be embedded within the phased antenna array.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] Implementations of the inventive concepts disclosed herein may be better understood
when consideration is given to the following detailed description thereof. Such description
makes reference io the inciuded drawings. which are not necessarily to scale, and in which some
features may be exaggerated and some features {nay be o~nined or may be represented
schematically in the interest of clarity. Like reference numerals in the drawings may represent
and refer to the same or similar element, feature. or function. In the drawings:
[0019] FIG. 1 shows a diagram illustrating an example embodiment ofa phased antenna array
testing environment, according to inventive concepts ofthis disclosure;
[0020] FIGS. 2A-C show block diagrams illustrating example embodiments of various WSA
antenna arrays with distinct example beamformer circuits, according to inventive concepts of this
disclosure;
[00211 FIG. 3 shows a flowchart illustrating a method of testing phased antenna arrays,
according to inventive concepts of this disclosure;
[0022] 121G. 4 slio\vs a block diagram illustrating an approach for determining the far field
response of ae phased antenna array 106 based on amplitudelphase responses for each of the
Atty. Dkt. No: lXCR047 (047141-13 1 I)
antenna elements of the phased antenna array is shown, according to inventive concepts of this
disclosure;
100231 FIG. 5 shows example simulation results illustrating phaselamplitude responses of the
antenna elements of the phased antenna array is shown, according to inventive concepts of this
disclosure;
j0024j [FIG. 6 shows an example far field response of the phased antenna array determined
using the antenna elements' phasela~nplituder esponses shown in FIG. 5 is shown, according to
inventive concepts of this disclosure: and
[00251 [FIG. 7 shows a flowchart illustrating another method 700 of testing phased antcnna
arrays according to inventive concepts ofthis disclosure.
100261 FIG. 8 shows a block diagram of a phased antenna array testing system, according to
inventive concepts of this disclosure.
[00271 FIG. 9 shows a block diagram of another phased antenna array testing system,
according to inventive concepts of this disclosure.
100281 'The details of various embodiments of the methods and systems are set forth in the
accompanying drawings and the description below.
DETAILED DESCRIPTION
100291 Before describing in detail embodiments of ihe inventive concepts disclosed herein, it
should be observed that the inventive concepts disclosed herein include, but are not limited to a
novel structural combination of components and circuits. and not to the particular detailed
configurations thereof. Accordingly, the structure, methods, functions, control and arrangement
of components and circuits have, for the most part, been illustrated in the drawings by readily
understandable bloclc representations and schematic diagrams, in order not to obscure thc
disclosure with structural details which will be readily apparent to those slcilled in the art, having
Atty. Dlt. No: 18CR047 (047141-131 1 )
the benefit of ihe description herein. Further, the inventive concepts disclosed herein are not
limited to the particular embodiments depicted in the diagrams provided in this disclosure, hut
should be construed in accordance with the language in the claims.
[0030] Methods and systems described herein allow phased antenna array testing methods that
are accurate, relatively fast (e.g., compared to conventional testing techniques), efficient. While
conventional antenna testing methods may allow for testing one or very few phased antenna
at-rays per day, the methods and systems described herein allow for testing many phased antenna
arrays per day. For instance, the methods described below with regard to FIGS. 3 and 7 can
allow for determining the radiation pattern of a phased antenna array in about seven seconds
instead of hours. The increased testing speed allows for using a relatively smaller number of
testing systems (or testing equipment') to test a given number (e.g., thousands) of phased antenna
arrays, and therefore, reduces the testing space used. The reduction in testing equipment used
reduces the testing cost and so does the reduction of testing space since anechoic chambers are
very costly and their cost increases with their size.
[0031j Also, conventional antenna testing methods and systems usually employ moving
mechanical parts (e.g., motors) that need to be maintained. These moving mechanical parts can
add to the complexity of the testing methods and slow the testing process. Specifically, using a
motor to rotate or move a robe antenna or a phased antenna array call be much slower and less
accurate than steering antenna elements of the phased antenna array by applying a set of time
delays or phase shifts.
100321 Referring now to the drawings, FIG. I shows a diagram illustrating an example
embodiment of a phased antenna array testing environment 100, according to inventive concepts
of this disclosure. In brief overview, the phased antenna array testing environment 100 can
include an antenna testing chamber 102, an antenna testing control system 104, a phased antenna
array 106, and one or more probe antennas, such as probc antennas 10%-108c which are referred
to hereinafter either individually or in combination as probe antenna(s) 108. The antenna testing
control system 104, the phased antenna array 106, and the one or more probe antennas 108 can
Atty. Dkt. No: 18CR047 (047141-131 1)
be arranged within the antenna testing chamber 102. l'he antenna testing control system 104 and
the one or more probe antennas 108 can be viewed as forming a phased antenna array testing
system 110 for testing the phased antenna array 106. While FIG. 1 shows a single phased
antenna array 106 being tested, the phased antenna array testing system 1 10 can be used to test a
plurality of phased antenna arrays 106 as discussed in further detail below.
I00331 The antenna testing chamber 102 can include a radio frequency (RF) anechoic chamber.
A RF anechoic chamber can be a room designed to completely, or substantially, absorb
reflections of electromagnetic waves radiated by the phased antenna array 106 or tile one or more
probe antennas 108. For instance, the walls, ceiling and floor of the RF anechoic chamber can be
made of or lined with electromagnetic wave absorbing material. The walls and ceiling of the RF
anechoic chamber can also be designed to block electromagnetic waves in the surrounding
environment from penetrating into anechoic chamber. The testing chamber 102 can be sized to
host the phased antenna array testing system 110 and the phased antenna array(s) 106 to be
tested. For instance;the~s?zc~ef the testing chamber 102 can be defined based on the sizes of
components of the phased antenna array testing system 110, the size of the phased antenna
arrayis) 106 to be tested, the number of phased antenna arrayis) to be tested (e.g., per a given
time duration), the distance(s) between the phased antenna array(s) 106 and the probe antenna(s)
108. or a combination thereof.
[0034] In some implementations, the phased antenna array testing system 110 and the phased
antenna array(s) 106 to be tested can be arranged in open space (or outdoor). Specifically,
embodiments for testing phased antenna arrays described in this disclosure can be performed in
an open space environment (not within a testing chamber 102). For instance, an electromagnetic
wave absorbing material can be laid on a portion of the ground between the phased antenna
array(s) 106 and the probe antcnna(s) 108 to prevent or mitigate reflections of the ground. Other
techniques may be employed to eliminate or mitigate background noise within the open space
testing environment.
Atty. Dkl.No: 18CR047 (047141-1311)
100351 An operator can use the phased antenna array testing system 110 to test the phased
antenna array 106 by measuring one or more performance parameters of the phased antenna
array 106. The phased antenna array 106 can be an electronically scanned array (ESA) antenna
or an adive ESA (AESA) antenna. The phased antenna array 106 can include a plurality of
antenna elements (also referred to as radiating elements) 112 that form an array. The array of
antenna elements 112 can be a one-dimensional (I-D) array, a two-dimensional (2-D) array, or a
three-dimensional (3-D) array. Each of the antenna elements 11 2 can act as a separate antenna
configured to receive, transmit, or alternate between transmitting and receiving radio frequency
(RF) signals. The phased antenna array 106 can include a network of RI: amplifiers and phase
shifiers (or time delay elements) communicatively coupled to the plurality of antenna elements
112. The network of RF amplifiers and phase shifters (or time delay elemelits) can allow for
steering of beams received or transmitted by the phased antenna array 106.
[0036] When manufaciured, the phased antenna array 106 can be designed to have specific
performance parameters (OFr-a dio characteristics) suclt as gain (G), directivity, radiation pattern,
beam width, radiated power (or effective isotropic radiated power (EIRP)), cross correlation
discrimination, gain-to-noise-temperature (GIT), error vector magnitude (EVM), adjacent
channel power ratio (ACPR), pulse quality, side lobe levels, signal-to-noise ratio (SNR), or a
combination thereof. However, due to manufacturing andlor design errors, the phased antenna
array 106 may perform as desired and the actual performance parameters of the phased antenna
array 106 may be different from the corresponding theoretical performance parameters defined,
for example, during the design process of the phased antenna array 106. The phased antenna
array testing processes described herein allow for measuring the actual performance parameters
,,,.
(or radio characteristics) of the phased antenna array 106.
[0037] During the testing processes described herein, the phased antenna array 106 can operate
(or act) as transmitting antenna while the probe antenna(s) 108 call operate as receiving
antenna(s), or the probe antenna(s) 108 can operate as transmitting anlenna(s) while the phased
antenna array 106 can operate (or act) as receiving antenna. For instance, the antenna testing
control system 104 can cause a probe antenna 108 to radiate electromagnetic waves, and the
Atty. Dlt. No: 18CR047 (047141-131 1)
phased antenna array 106 can receive, responsive to the tra~lsmission of the electromagnetic
waves, corresponding RF signals. The antenna testing control system 104 may cause the phased
antenna array 106 to radiate specific electromagnetic waves, and the probe antenna(s) 108 can
receive, responsive to the transmission of the electromagnetic waves, corresponding receive RF
signals. The antenna testing co~ltrols ystem 104 can determine (or compute) one or more actual
performance parameters of the phased antenna array 106 based on the received RF signals.
[0038J The probe antenna(s) 108 cm include a horn a~lte~maa, loop probe antenna, a
rectangular antenna, a dipole antenna probe, or other type of antenna known to a person skilled
in the art. The probe antenna(s) 108 can be single polarized or dual polarized. The one or more
probe antenna(s) 108 lnay be arranged at fixed position(s) relative to the phased antenna array
106. The one or more probe antenna(s) 108 may be arranged or positioned at different angles
with respect to an axis 114 that is orthogonal to a front surface (planar or curved) of the phased
antenna array 106 along which the antenna elements 112 are arranged. For instance, probe
antenna 108a can be arranged.at angle 00 = O", the probe antenna 108b can be arranged at angle
8, = 45", and the probe antenna 10% can be arranged at angle 02 = 60'. The points 1 16 indicate
can be indicative of various angles or positions along which the one or more probe antennas 108
may be arranged. The axis 114 may be pointing to (or passing through) a center point of the
phased antenna array 106. The angles with respect to the axis 114 (or the points 116) at which
the probe antennas 108 may be positioned can be defined in a three-dimensional (3D) space. The
points 116 defining potential angles, relative to the axis 1 14, at which (or along which) the probe
antennas 108 can be positioned or arranged can fonn a half sphere or a two-dimensional (2D)
plane.
[0039] Referring to FIGS. 2A-2C, various arrangements of probe antennas 108 are illustrated,
according to inventive concepts of this disclosure. As illustrated in FIG. 2A, the phased antenna
array testing system 110 can include a horizo~ltally polarized probe antenna 108-1 and a
vertically polarized probe antenna 108-2, or more generally at least two differently polarized
probe antennas. The probe antennas 108-1 and 108-2 are also referred to hereinafter individually
or collectively as probe antenna(s) 108. The differently polarized probe antennas 108-1 and 108-
Atty. Dkt. No: 18CR047 (047141-1 31 1)
2 may be arranged or positioned relatively close to each other (e.g., with correspond~nga ngles
relative to the axis 1 14 that are different by 0" to 3' or 0' to 5") or substantially apart from each
other (e.g., with corresponding angles relative to the axis 114 that are different by 10" or more).
The differently polarized probe antennas 108-1 and 108-2 may be positioned at different
altitudes (e.g., relative to the ground or the floor of the antenna testing chamber 102) or along the
same altitude. The differently polarized probe antennas 108-1 and 108-2 allow for radiating or
receiving dual polarized electromagnetic waves and, therefore, measuring performance
parameters that are associated with distinct polarization components of the phased antenna array
106. The phased antenna array testing system 110 may include multiple pairs of differently
polarized probe antennas.
[0040] Referring to FIG. 2B, the phased antenna array testing system 110 can include a
plurality of probe antennas 108-1 through 108-n (referred to herein individually or in
combination as probe antenna(s) 108) operating at different frequency bands associated with
diffel.ent center frequencies fi,$, ...,$;, where n is an integer greater than 1. Each robe antenna
108-i, where i = 1,2, ... , n, can be configured to operate at a corresponding center frequency5 of
the frequencies fi, ,fi, . . ., ,fi. The probe antennas 108-1 ihrough 108-n can be arranged or
positioned relatively close to each other (e.g., with corresponding angles relative to the axis 114
that are different by 0' to 3' or 0" to 5') or substantially apart from each other (e.g., with
corresponding angles relative to the axis 114 that are different by 10" or more). The probe
antennas 108-1 through 108-n may be positioned at different altitudes (e.g., relative to the
ground or the floor of the antenna testing chamber 102) or along the same altitude. The phased
antenna array testing system 110 may include a plurality of n-tuples of probe antennas (such as
the n-tuple 108-1 through 108-n). For instance, at least two of the n-tuples of probe antennas can
be polarized differently (e.g., one n-tuple can be horizontally polarized and another can be
vertically polarized). Probe antennas 108-i operating at a given center frequency ,f; can be
positioned at different locations (e.g., at different angles with respect to axis 114). The use of
probe antennas 108-1 through 108-n operating at distinct frequency bands allows for radiating or
receiving electromagnetic waves at different frequencies and assessing the performance
Atty. Dkt.No: 18CR047(047141-1311)
parameters of the phased antenna array 106 over a wide frequency band (e.g., the combination of
the frequency bands at which the probe antennas 108-1 through 108-n operate). The use of probe
antennas 108-1 through 108-n operating at distinct frequency bands can allow determining the
operating frequency band ofthe phased antenna array 106.
[0041] Referring to FIG. 2C, the phased antenna array testing system 110 can include a probe
antenna 108 configured lo move relative to the phased antenna array 106. A positioning system
(not shown in FIGS. 1 and 2A-2C) can cause the probe antenna 108 to move, for example, along
a predefined path (e.g., one or more straight lines or curves) or between predefined positions
(e.g., positions indicated by points 11 6 in FIG. 1). The positioning system may cause the phased
antenna array 106, or both probe antenna 108 and the phased antenna array 106, to move
according to corresponding predefined path(s) or between corresponding predefined positions.
Using a moving probe antenna 108 andlor a moving phased antenna array 106 can facilitate
measuring performance parameters for a plurality of phased antenna arrays 106 or measuring
additional performmce'.pn;ameterr~( q.rad;ia tion pattern or one or more side lobe levels) of a
phased antenna array 106. For instance, when testing a plurality of phased antenna arrays 106,
the antenna testing control system 104 may cause the phased antenna arrays 106 to be activated
one at a time and cause the probe antenna 108, or the plurality of phased antenna arrays 106, to
move according to a predefined motion pattern, for example, such that the active phased antenna
array 106 is positioned at a predefined location relative to the probe antenna(s) 108. For
example, the antenna testing control system 104 may (1) cause the phased antenna arrays 106 to
be displaced, along a predefined path, by a specific distance, (2) activate the phased antenna
array 106 located at a specific position, (3) cause radiation of electromagnetic waves between the
active phased antenna array and the probe antenna(s) 108, and (4) repeat the steps (1) through (4)
until all phased antenna arrays 106 are activated for testing. In another example, the antenna
testing control system 104 may cause the probe antenna 108 to move according to a plurality of
predefined displacement and activate a distinct pliased antenna array 106 after each displacement
until all phased antenna arrays 108 are tested.
Atty. Dkt. No: 18CR047 (047141 -1 3 11)
[0042] Other arrangements of probe antennas 108 are also contemplated by the current
disclosure. For example, the phased antenna array testing system 110 can include one or more
probe antennas 108 according to a combination of the arrangement discussed above with regard
to FIGS. 2A-2C. For instance, the phased antenna array testing system 11 0 can include at least a
pair of differently polarized probe antennas 108 that are configured to move relative to the
phased antenna array 106. The phased antenna array testing system 110 can include an n-tuple of
probe antennas 108 that are configured to operate at different frequency bands and move relative
to the phased antenna array 106. The phased antenna array testing system 110 can include at
least two n-tuples of probe antennas (with probe antennas 108 in each n-tuple operating at
differcnt frequency bands) that are polarized differently (e.g., one n-tuple can have horizontal
polarization and another can have a vertical polarization). The at least two n-tuples of probe
antennas may be configured to move relative to the phased antenna array 106.
[0043] Referring back to FIG. 1, the antenna testing control system 104 can be
co~n~nunicativelcyo upled-to.$hcphased antenna array(s) 106 and the probe antenna(s) 108. The
antenna testing control system 104 can include a combination of one or more electronic devices
and one or more electriclelectronic circuits. For instance, the antenna testing control system 104
can include a signal generator circuit, a network analyzer, a signal analyzer, a controller, a
processor, a memory, a computing device, or a combination thereof. The antenna testing control
system 104 can control electromagnetic wave radiation by the phased antenna array(s) 106 or the
probe antenna(s) 108. For example, the antenna testing control system 104 can generate and
provide KF signals to be transmitted as electromagnetic waves by the phased antenna array(s)
106 or the probe antenna(s) 108. The antenna testing control system 104 can control
configuration schemes (or beam steering) ofthe phased antcnna array(s) 106. The antenna testing
control system 104 can send instructions to the phased antenna array 106 indicative of a
configuration scheme (or phase configuration scheme). A configuration scheme (or a phase
configuration scheme) can be indicative of (or can define) a group of antenna elements 1 12 of
the phased antenna array 106 to be activated, phase shifts (or time delays) for various antenna
elements 112 (e.g., all the antenna elements 112 or a group of antenna elements to be activated),
Atty. Dkt. No: 18CR047 (047141-13 11)
attenuations or power amplifications values for various antenna elements 1 12, or a combination
thereof. The antenna testing control system 104 can control the order and timing according to
which the phase configuration schemes are implemented by the phased antenna array 106.
[0044] The antenna testing control system 104 can obtain RF signals received by the receiving
antenna(s) (the probe antenna(s) 108 or the phased antenna array 106) and process the received
RF signals received to determine or compute performance parameters of the phased antenna
array 106. The antenna testing control system 104 can calculate the performance parameters of
the phased antenna array 106 and provide the calculated performance parameters for storage in a
memory or remote database, or for display on a display device communicatively coupled to the
phased antenna array testlng system 110. may also be communicatively coupled to a positioning
system for controlling positions of the phased antenna array(s) 106 and the probe antenna(s) 108.
I00451 The antenna testing control system 104 can further include a positioning system (not
shown in FIG. 1). The positioning system can be communicatively coupled to the antenna testing ... d < b
control system 104. The positioning system can include one or more mechanical structures for
mechanically supporting the phased antenna array 106 or the probe antenna(s) 108. The
positioning system can include a motor, wheels, or other mechanical components to cause the
phased antenna array 106 or the probe antenna(s) 108 to automatically move between different
positions or along a predefined path. For example, the positioning system can receive
instructions (or signals indicative of instructions) from the antenna testing control system 104
and cause Llie phased antenna array 106 or the probe antenna(s) 108 to move between different
predefined positions or along a predefined path, for example, as described above.
100461 Referring to FIG. 3, a flowchart illustrating a method 300 of testing phased antenna
arrays is shown, according to inventive concepts of this disclosure. In brief overview, the method
300 can include positioning a phased antenna array and an antenna probe at relative positions
with respect to each other with one of them acting as a transmitting antenna and the other acting
as a receiving antenna (BLOCK 302), and causing the transmitting antenna to radiate a plurality
of electromagnctic waves sequentially (BLOCK 304). The method 300 can include causing the
Atty. Dlt. No: 18CR047 (047141-13 1 1)
phased antenna array to operate, during transmission of each electromagnetic wave of the
plurality of electromagnetic waves, according to a corresponding configuration scheme (BLOCK
306), receiving, by the receiving antenna, responsive to each radiated electromagnetic wave, and
one or Inore corresponding receive radio frequency (RF) signals (BLOCK 308). The method 300
can include determining, for each antenna element of the plurality of antenna elements, a
corresponding signal response using the receive RF signals (BLOCK 310), and determining one
or more perfor~na~icpea rameters of the phased antenna array using the determined signal
responses for the plurality of antenna elements (BLOCK 3 12).
[0047] The method 300 can include positioning a phased antenna array 106 and an antenna
probe 108 at relative positions with respect to each other with one of them acting as a
transmitt~ng antenna and the other acting as a receiving antenna (BLOCK 302). During the
process of testing the phased antenna array 106, the phased antenna array 106 can act a
transmitting antenna (\vhile the probe antenna LO8 can act as the receiving antenna) or as a
receiving antenna (while ihe probe antenna 108 can act as the transmitting antenna). Under the
principal of ieciprocity, the recelve and transmit properties of the phased anteillla array 106 are
identical. For instance, the radiation pattern of the phased antenna array 106 is the same in the
transmit mode and the receive mode. Accordingly, when measuring the performance parameters
of the phased antenna array 106, the phased antenna array can be arranged to operate as the
transmitting antenna or the receiving antenna.
[0048J The antenna testing control system 104 can include, or can have access to, a testing
schedule (or testing plan). The testing schedule can include indications of which entity among
the phased antenna array 106 and the probe antenna 108 to act as the transmitting antenna and
which entity to act as the receiving entity, the number of probe antennas 108 used, the relative
locations of the phased antenna array 106 and the probe antenna(s) 108, a sequence of transmit
RF signals to be transmitted (e.g., as radiated electromagnetic waves), timing information (e.g.,
time of transmission of each transmit RF signal or time intervals between successive
transmissions of transmit RF signals), a plurality of configuration schemes ofthe phased antenna
array, motio~i information (e.g., where and/or when the probe antenna 108 or the phased antenna
Any. Dkt. No: 18CR047 (047141-131 1)
array 106 islare to be moved), or a combination thereof. The antenna testing control system 104
can include, or can have access to, indications of properties of the probe antenna 108 (e.g.,
performance parameters, geometry parameters such as size and shape, type of probe antenna 108,
or a combination thereoo. The antenna testing control system 104 can include, or can have
access to, indications of design properties of the phased antenna array 106, such as the number of
antenna elements 112 in the phased antenna array 106, the arrangement of the antenna elements
11 2 (e.g., number of rows and columns in the array and the number of antenna elements in each
row or column), the spacing between the antenna elements 112, positions of the antenna
elements in the three-dimensional space, the orientations of the antenna elements, the shape of
the phased antenna array 106 (e.g., planar or curved), or a combination thereof.
100491 At the start of the process of testing the phased antenna array 106, a user (e.g., a
technician) may manually position or mount the phased antenna array 106 and the probe antenna
108 on corresponding mechanical support elemenis. The mechanical support elements can be
positioned (e.g., fixed) at predefined testing positions. The positions of the mechanical support
eleme~its can be adjustable, and the antenna testing conlrol system 104 can instruct the
positioning system to move probe antenna 108, the phased antenna array 106, or the
conesponding mechanical support elements to predefined positions at which the phased antenna
array 106 and the probe antenna 108 are to be tested. The phased antenna array 106 can be
positioned to face the probe antenna 108 (or one of the probe antennas I08 if more than one is
used). for example, as illustrated in FIG. 1.
[0050] Positioning the probe antenna 108 can include positioning the probe antenna 108 at a
near field location relalive lwthe pt~aseda ntent~aa rray 106. For instance, the distance between
the phased antenna array 106 and the probe antenna 108 can be less than the dominant
wavelengtll h of the transmitted KF signal (or radiated electromagnetic wave), less than 2xh less
than 3 x h or less than 5xh. Such arrangement can allow for using a relatively small antenna
testing chamber 102. In some cases, the user or the position~ngs ystem may position the probe
antenna 108 at a far field location relative to the phased antenna array 106. In such cases, the
Atty. Dlit. No: 18CR047 (047141-13 11)
distance between the phased antenna array 106 and the probe antenna 108 may be, for example,
greater than 5x1, greater than iOxh, or greater than some other predefined distance.
[0051] Positioning the probe antenna 108 can include positioning a single dual polarized probe
antenna 108 or positioning at least two probe antennas 108 with distinct polarizations (e.g.,
including one horizontally polarized probe antenna and one vertically polarized probe antenna)
as discussed above with regard to FIG. 2A. For instance, the user or the positioning system can
position a pair of antennas 108-1 and 108-2 that are distinctly polarized or a plurality of such
pairs as discussed above with regard to FIG. 2A. Using a dual polarized probe antenna 108 or a
pair of distinctly polarized probe antennas, such as probe antennas 108-1 and 108-2 of FlG. 2A,
can allow for assessing the co-polarized and cross-polarized response or performance of the
phased antenna array 106.
[0052j Positioning the probe antenna 108 can include positioning a plurality or probe antennas
108 at different positions relative lo the phased antenna array 106 as discussed above with regard
,*,,,
to FIG. I. The plurality of probe antennas may include one or more n-tuples each of which
associated with n distinct operating center frequencies fi, fz, ..., f,, as discussed above with
regard to FIG. 2B. Using a plurality of probe antennas operating at various center frequencies
allows for assessing the performance parameters of the phased antenna array 106 over a
relatively wide frequency band. For example, when using a single probe antenna 108, the testing
of the phased antenna array 106 is constrained to the operating frequency band of that probe
antenna 108. In some cases, the probe antenna(s) 108 andlor the phased antenna array 106 may
be configured to move as discussed above with regard to FIG. 2C.
" . & ,
[0053] The method 300 can include causing the transmitting antenna to radiate a plurality of
electromagnetic waves sequentially (BLOCK 304). The antenna testing control system 104 can
send instructions to the transmitting antenna (the phased antenna array 106 or the probe
antenna(s) 108) to cause the transmitting antenna to radiate each of the plurality of
electromagnetic waves, for example, according to the testing schedule. The antenna testing
control system 104 may send a separate instruction or coinrnand for each elecironlagnetic wave
Atty. Dkt. No: 18CR047 (047141-131 1)
to be radiated by the transmitting antenna, or send one instruction commanding the transmitting
antenna to transmit or radiate the electromagnetic waves according to a specified time schedule.
The plurality of electro~nagnetic waves rnay correspond to a single transmit RF signal or a
plurality of distinct transmit RF signals (e.g., transmit RF signals associated with distinct
bandwidths or center frequencies). For example radiating the plurality of electro~nagneticw aves
may include the transmitting antenna transmitling a single transmit RF signal repeatedly at
multiple time instances, transmitting time-shifted versions of the single transmit RF signal at tlie
multiple time instances, or transmitting distinct transmit R17 signals at the multiple time
instances. In general, the antenna testing control system 104 can control the transmit RF signal(s)
to be transmitted by the transmitting antenna, the radiation time of each electromagnetic wave,
the order according to which the plurality of elcctro~nagnetic waves are transmitted, or a
combination thereof.
[0054) In the case where multiple probe antennas 108 acting as transmitting antennas are used
(e.g., as discussed with regard to FIGS. 1, 2A and 2B), the probe antennas 108 may transmit
simultaneously or sequentially, one at a tirne. Also, if a moving probing antenna 108 (e.g., as
d~scussedw ith regard to FIG. 2C) is used as the transmitting antenna, the probe antenna 108 {nay
perform one or Inore transnlissions while in one location, move to another location to perform
one or more other transmissions, then to a third location and so on and so forth. The probe
antenna 108 may transmit (or radiate) electromagnetic waves while moving. The antenna testing
control system 104 can have access to the location of the moving probe antenna 108 (or the
location of a moving phased antenna array 106) at each instance an electromagnetic wave is
rad~atedb y the transmitting antenna or received by the receiving antenna.
LO0551 The method 300 can include causing the phased antenna array 106 to operate, during
transmission of each electromagnetic wave of the plurality of electromagnetic waves, according
to a corresponding configuration scheme (BLOCK 306). Each configuration scheme can be
indicative of the antenna elements 112 of the phased antenna array 106 (e.g., all or a subset of
the antenna elements 112) to be activated, the phase shift (or time delay) to be applied to each
antenna element, the power amplification to be applied to each antenna element 112, or a
Atty. Dkt. No: 18CR047 (047141-131 1)
combination thereof. Each configuration scheme can be associated with a corresponding
electromagnetic wave radiated by the transmitting antenna. The antenna testing control system
104 may send a separate instruction to the phased antenna array 106 for each configuration
scheme to be applied (e.g., prior to radiating the corresponding electromagnetic wave by the
transmitting antenna), or may send one instruction indicative of the plurality of the configuration
schemes and a time schedule according to which to apply each of the configuration schemes.
100561 In the case where the phased antenna array 106 operates as the transmitting antenna, thc
phased antenna array 106 may apply or implement each configuration scheme prior to radiating
the corresponding electromagnetic wave. For instance, the phased antenna array 106 can receive
an indication of a transmit RF signal and an indication of a configuration scheme. The phased
antenna array 106 can apply the configuration scheme (e.g., by activating one or more antenna
elements 112, applying to one or more antenna elements 112 corresponding phase shifis or time
delays, applying lo one or more antenna elements 112 corresponding power amplifications, or a
combination thereof), and transmit the transmit RF signal by each of the active antenna elemen&
112. The electromagnetic wave radiated or transmitted by the phased antenna amay 106 can be
the sum of the waves radiatedltransmitted by the active antenna elements 112. The phased
antenna array 106 can then apply another configuration scheme and radiate a new
electromagnetic wave as each of the now active antenna elements 112 transmits the same (or
another) transmit RF signal. The phased antenna array 106 can apply a different configuration
scheme for each electromagnetic wave to be transmittedlradiated.
[0057] In the case where the phased antenna array 106 operates as the receiving antenna, the
phased antenna array l06may apply or implement each configuration scheme prior to (or while)
the probe antenna(s) 108 radiating the corresponding electromagnetic wave. For instance, the
antenna testing control system 104 can instruct the probe antenna 108 to transmit or radiate an
electromagnetic wave (e.g., by providing an indication of a transmit RF signal) and instruct the
phased antenna array 106 to apply a configuration scheme. The phased antenna array 106 can
apply the configuration scheme (e.g., by activating one or more antenna elements 112, applying
to one or more antenna elements 112 corresponding phase shifts or time delays, applying to one
Atty. Dkt. No: 18CR047 (047141-13 11)
or more antenna elements 112 corresponding power amplifications, or a combination thereof)
prior to the start of transmission or radiation of thc electromagnetic wave by the probe antenna
108. The phased antenna array 106 (or active antenna elements 108 thereof) can receive the
radiated electromagnetic wave while operating according to the applied configuration scheme.
The phased antenna array 106 can then apply another configuration scheme to receive another
electromagnetic wave radiated or transmitted by the probe antenna 108. This process can be
repeated with a different (or separate) configuration scheme applied by the phased antenna array
106 each time. The probe antenna 108 can radiate or transmit the same electromagnetic wave
(e.g., corresponding to the transmit RF signal) repeatedly. In other words, the plurality of
electro~nagneticw aves transmitted by the probe antenna 108 can include (or represent) multiple
tra~is~nissionosft he same transmit RF signal at different time instances.
[0058] Causing the phased antenna array 106 to operate, during transmission of each
electromagnetic wave of the plurality of electromagnetic waves, according to a corresponding
configuration scheme can include activating the plurality of antenna elements 112 one ai a time
such that each antenna element is activated during transmission of a corresponding
electro~nagneticw ave of the plurality of electromagnetic waves. Each configuration scheme can
be indicative of a corresponding antenna element 1 12 of the plurality of antenna ele~ne~iotfs the
phased antenna array 106 to be activated. For instance, when operating as the transmitting
antenna, the phased antenna array 106 may activate a first antenna element 112 and cause the
activated first antenna element 112 to transmit a transmit RF signal while the reset of antenna
elements 112 are deactivated. The phased antenna array 106 may then activate a second antenna
element 112 (while deactivating the first antenna element 112) and cause the second antenna
, ,.,
element 112 to transmit the transmit RF signal (or another transmit RF signal). The phased
antenna array 106 may continue activating the antenna elements 112 one at a time and causing
the activated antenna element 112 to transmit the transmit RF signal (or a corresponding transmit
RF signal), for example, until all antenna elements 112 of the phased antenna array 106 have
been activated and transmitted transmit RI' signal(s).
Alty. Dlt. No: 18CR047 (047141-131 1)
100591 When operating as thc receiving antenna, the phased antenna array 106 may activate
(e.g., based on instruction or command from the antenna testing control system 104) an antenna
element 112 such that the activated antenna element 112 receives a first electromagnetic wave
radiated by the probe antenna 108. The phased antenna array 106 may then activate another
antenna element 1 12 (while deactivating the previously activated antenna element 112) such that
the now activated antenna element 112 receives a second electromagnetic wave radiated by the
probe antenna 108. The phased antenna array 106 may continue activating the antenna elements
112 one at a time and having each activated antenna element 112 receive an electromagnetic
wave radiated by the probe antenna 108, for example, until all antenna elements 112 of the
phased antenna array 106 have been activated.
I00601 Causing the phased antenna array 106 to operate, during transmission of each
electromagnetic wave of the plurality of electromagnetic waves, according to a corresponding
configuration scheme can include the phased antenna array 106 (e.g., based on instruction(s) or
command(s) from the antenna testing control system 104) phase steering the plurality of antenna
elements 1 12, during transmission of each electroinagnetic wave, according to a respective phase
coding scheme. Each phase coding scheme can define a corresponding set of phase shifts (or a
corresponding set of time delays) applied to the plurality of antenna elements 112 during
transmission of the corresponding electromagnetic wave. That is, each phase coding scheme can
define for each antenna element 1 12 a corresponding phase shift (or a corresponding time delay)
according to which that antenna element 112 is to operate. Each phase coding scheme may also
define a set of power a~nplifications applied to the plurality of antenna elements 112 during
transmission of the corresponding electromagnetic wave. That is, each phase coding scheme can
define for cach antenna clement 112 a corresponding power amplification according to which
that antenna element 1 12 is to operate.
[0061] For instance, when operating as the transmitting antenna, the phased antenna array 106
can phase steer the antenna elements 112 according to a first phase coding scheme and cause the
antenna elements 112 to transmit a transmit RF signal while operating according to the first
phase coding scheme. As such, the antenna elements 112 can simultaneously transmit various
Atty. Dkt. No: 18CR047 (047141-13 11j
time delayed (or phase shifted) versions of the transmit RF signal that add up to form an
electro~nagneticw ave radiated by the phased antenna array. The phased antenna array 106 can
phase steer the antenna elements 1 12 according to a second phase coding scheme and cause the
antenna elements 112 to transmit the transmit RF signal (or another transmit RF signal) while
operating according to the second phase coding scheme. The phased antenna array 106 can
continue phase steering the antenna elements 112 and causing the antenna elements 112 to
transmit the transmit RF signal until all phase coding schemes are applied to the antenna
elements 112. By applying various phase coding schemes when transmitting the transmit RF
signal(s), the phased antenna array 106 can radiate a plurality of electromagnetic waves
sequentially. The electromagnetic waves radiated by the phased antenna array 106 may be
different from each other, for example, when distinct phase coding schemes arc applied to the
antenna elements 112.
[0062] When operating as the receiving antenna, the phased antenna array 106 can phase steer
the antenna elements 1 12,accw~ding,taof irst phase coding scheme to receive an electromagnetic
wave radiated by the probe antenna 108. While all antenna elements 112 are exposed to the same
magnetic wave (radiated by the probe antenna 108), the antenna elements 112 can receive
different phase shifted (or time delayed) versions of the electro~nagnetic wave (or a
corresponding RF signal) given that different phase shifts (or time delays) can be applied to
separate antenna elements 112. The phased antenna array 106 can phase steer the antenna
elements 112 according to a second phase coding scheme to receive another electromagnetic
wave radiated by the probe antenna 108. The phased antenna array 106 can continue phase
steering the antenna ele~nents 112 until all phase coding schemes (e.g., of a predelined set of
coding schemes) are sequentially applied to the antenna elements 112 to receive a plurality of
electromagnetic waves sequentially radiated by the probe antenna 108. The plurality of
electromagnetic waves sequentially radiated by the probe antenna 108 may be associated with a
single transmit RF signal that is repeatedly transmitted by the probe antenna 106, or may be
associated with distinct transmit RF signals.
Atty. Dkt. No: 18CR047 (047141-131 1)
[0063] In some instances, causing the phased antenna array 106 to operate, during transmission
of each electromagnetic wave of the plurality of electromagnetic waves, according to a
corresponding configuration scheme can include can include activating a group of antenna
elements of the plurality of antenna elements 112 and phase steering the antenna elements of the
activated group. For instance, the phased antenna array 106 (whether operating as the
transmitting antenna or the receiving antenna) can activate the plurality of antenna elements 112
one group (e.g., block of antenna elements) at a time. The phased antenna array 106 can
sequentially apply to each activated group of antenna elements a corresponding plurality of
phase coding schemes. For example, four distinct phase coding schemes may be sequentially
applied to a group of four activated antenna elements 1 12. Each coding scheme defines the phase
shifts (or time delays) andior power amplifications to be applied to the antenna elements of the
corresponding group of active antenna elements. Each configuration scheme can define a group
of antenna elements to he activated and a phase coding scheme to be applied to that group of
antenna elements. This approach, where each configuration scheme defines a corresponding
..,., .,,
group (or block) of antenna elements to be activated and a corresponding phase coding scheme
to be applied to the group of active antenna elemenis, allows for testing blocks of antenna
elements separately.
100641 The method 300 can include the receiving antenna (the phased antenna array 106 or the
probe antenna 108) receiving, responsive to each electromagnetic wave radiated by the
transmitting antenna, a corresponding receive RF signal (BLOCK 308). When the phased
antenna array 106 operates as the receiving antenna, the receive RF signal can be a summation of
signals received by active antenna elements 112. For example, when the antenna elements 112
are activated one at a time, each receive RF signal can bc a signal received by the corresponding
active antenna element phased shifted (or time delayed) by any phase shift (or time delay) value
associated the active antenna element 112 andlor amplified by an amplitudeipower amplification
value associated with the active antenna elements. When the antenna elements 1 12 are activated
one group at a time, each receive RF signal can be a su~n~natioonf phased shifted (or time
delayed) andlor amplified versions (e.g., according to phase coding scheme applied to the group
24
4836-4692-6683
Atty. Dkt. No: 18CR047 (047141-131 1)
of antenna elements) of signals received by the corresponding active group of antenna elements.
When separate phase coding schemes are applied to all the antenna elements 112, one phase
coding scheme at a time, each receive RF signal can be a summation of phased shifted (or time
delayed) and/or amplified versions (e.g., according to the phase coding scheme applied) of
signals received by the plurality of antenna elements 112 of the phased antenna array 106. The
phase shifting (or time delays) and/or the amplificatio~is can be applied by the network of RF
amplifiers and phase shifiers (or time delay elements) of the phased antenna array 106 or by a
processor (or controller) of the phased antenna array 106.
[0065] When the phased antenna array 106 operates as the transmitting antenna, each receive
RF signal can represent the signal received by the probe antenna 108 (responsive to a
corresponding electromagnetic wave rad~atedb y the phased antenna array 106) amplified by any
amplitude/power amplification associated with the probe antenna array 108. In the case where
multiple probe antennas 108 acting as receiving antennas are used (e.g., as discussed with regard
to FIGS. 1, 2A and B;, the probe antennas 108 may receive electromagnetic waves
simulta~ieously or sequentially (e.g., activated one at a time). Also, if a moving probing antenna
108 (e.g., as discussed with regard to FIG. 2C) is used as the receiving antenna, the probe
antenna 108 may receive one or Inore radiated electromagnetic waves while in one location,
move to another location to receive one or more other waves, then to a third location and so on
and so forth. The probe antenna 108 may receive electromagnetic waves while moving. The
antenna testing control system 104 can have access to the location of the moving probe antenna
108 (or the location of a moving phased antenna array 106) at each instance an electromagnetic
wave is radiated by the transmitting antenna or received by the receiving antenna.
[OO66] The method 300 can include determ~ning, for each antenna element 1 12 of the plurality
of antenna elements 112, a corresponding signal response using the receive RF signals (BLOCK I I 310) The antenna testing co~ltrols ystem 104 can obtain a plurality of receive RF signals from
the receiving antenna As discussed above, each of the plural~ty of receive RF signals can be
associated with a corresponding antenna clement 112 (act~nga s a transmitter or as a receiver). a
corresponding group of active antenna elements (acting as transmitters or as receivers) and a
Atty. Dkt. No: 18CR047 (047141-131 1)
corresponding phase coding scheme applied to that group of active antenna elements, or a
corresponding phase coding scheme applied to the plurality of antenna elernents 112 (acting as
transmitters or as a receivers) of the phased antenna array.
[0067] Assuming that the phased antenna array 106 has K (K is an integer) antenna elements
and that N (N is an integer) receive RI"ignals obtained by the antenna testing control system
104, each receive RF signal Y,(o) (in the frequency domain) can be described as:
1 he integer z represents an index of signal transmission (or reception) events by the transmitting
antenna (or the receiving antenna) or an index of the receive RF signals. The integer k represents
an index of the antenna elements 112 of the phased antenna array 106. The signal X(w)
represents the transmit RF signal (in the frequency domain) used by the transinitling antenna,
and w is the angular frequency. Each parameter W,,,, can be a complex weighting parameter
associated with the k-th antenna element and defined, for example, by the phase coding scheme
applied during the i-th transmissionlreception event. For instance, tlie complex weighting
parameter W,,, can be indicative of the time delay (or phase shift) andlor power amplification
applied by the phased antenna array 106 to the signal transmitted or received by the k-th antenna
element during the i-the transmissionlreception event. As used herein a transmission or reception
event refers to a transmission (or a reception) of an electromagnetic wave by the transmitting
antenna (or receiving antenna). The con~plexw eighting parameters W,,k for all k = 1, ..., K and
all i = 1, . . ., Nare known to the antenna testing control system 104 since these parameters can be
predefined in the -configurntion schemes (or phase coding schemes) applied by the phased
antenna array 106 during the various transmissionlreception events. Each parameter Ak can be a
complex weighting parameter associated with the k-th antenna element that can be indicative of
phase shift and signal attenuation due to the distance between the k-th antenna element and the
phased antenna array, the gain of the probe antenna 108 at the direction of transmission or
reception, the gain of the k-th antenna element at the direction of transmission or reception, or a
combination thereof. For instance, thc complex weighting parameter Ak can be indicative of the
Atty. Dkt. No: 18CR047 (047141-131 1)
time delay (or phase shift) andlor power amplification applied by the phased antenna array 106
to the signal transmitted or received by the k-th antenna element during the i-th
transmissionlreceptio~i event. The cornplex weighting parameters Ak for It =1, ..., K are the
unknowns in the set of equations (1).
[0068j The formulation in the set of equations (1) illustrates that each receive RF signal Y,(w)
can be expressed, in the frequency domain, as a weighted sum of the transmit RF signal X(w). In
the case where all the antenna elements 112 of the phased antenna array 106 are activated with a
distinct phase coding scheme applied by the phased antenna array 106 during each of the
tran~missionireceptione vents, the complex weighting parameters Ak can be non-zero for all k =
1. ..., K, and the complex weighting parameters WLacka n be non-zero for all i=I, ..., Nand all k
- - 1, ..., K. In the case where the antenna elements 1 12 are activated one group at a time, the set
of equations (I) can be re-written as
where S, represents the set of indices for the active antenna elements during the i-th
transmissionireception event. In the case where the antenna elements 112 are activated one at a
time, the set of equations ( I ) reduces to
where the integer q(ii represents the index of the active antenna element during the i-th
transmissionireception event.
[0069] Since the transmit RF signal X(w) and the complex weigliting parameters WLaakr e
already ltnown, the antenna testing control system 104 can solve for the complex weighting
parameters Ak using any of the sets of equalions ( I ) , (2), or (3) depending on the type of
configuration schemes applied or implemented by the phased antenna array 106. For example,
using equation (3), the antenna testing control system 104 can compute A,(,) as:
Atty. Dkt. No: 18CR047 (047141-13 11)
The antenna testing control system 104 can solve the set of equations (I) for the complex
weighted parameters Ak as long as N 2 K and the N equations (1) are linearly independent. The
phase coding schelnes used can be selected or designed (e.g., by the antenna testing control
system 104) such that the set of equations (1) are linearly independent with N 2 K. For the set
of equations (2), the antenna testing control system 104 can solve each subset of equations
associated with a corresponding group of activated antenna elements separately given that the
number of equations for each group (or block) S, of active antenna elements is greater than or
equal to the number of antenna elernents in that group (or block). The phase coding schemes
associated with each group (or block) of antenna elements S, can be selected or designed (e.g., by
the antenna testing control system 104) to be greater than the number of antenna elernents in that
group (or block) aid such that the corresponding equations (among the set of equations (2)) are
linearly independent.
10070) Once tlie complex weighting parameters A,are determined, ihe antenna testing control
systeln 104 can determine a signal response for each antenna element 112. The antenna testing
control system 104 can remove from each complex weighting parameters Akthe effect of the
probe antenna gain (along ihe angle of arrival!deparlure of the received!transmitted
electromagnetic wave), the time delay due to the electrornagnetie wave propagation between the
probe antenna and the k-th antenna element, and electromagnetic wave attenuation (if any) due to
the electromagnetic wave propagation between the probe antenna and the k-th antenna element.
For instance, the antenna testing control system 104 can compute a new set of complex
weighting parameters Bk such that
where Gp(8, q) represents the gain of the probe antenna 108 along the angle of electromagnetic
wave propagation, and the parameter pkelWS represents the amplitude attenuation and the phasc
Atty. Dkt. No: 18CR047 (047141-1 31 1)
shift due to electromagnetic propagation between the probe antenna 108 and the k-th antenna
element. In some instances, the amplitude attenuation parameter p,, can be equal to 1. The
radiation pattern of the probe antenna 108 may be known in advance to the antenna testing
control system 104. For instance, a representation of the radiation pattern of the probe antenna
108 [nay be stored in a memory accessible by the antenna testing control system 104. The
antenna testing control system 104 can precompute the parameter pke'os (for each antenna
element with index k) based on the distance between the probe antenna 108 and the k-th antenna
element.
100711 The antenna testing control system 104 can determine the signal response for each
antenna element as BkX(w). If the phased antenna array 106 is acting as the transmitting
antenna, the signal response BkX(w) can be viewed as the RF signal radiated at the surface of
the k-th antenna element when no weighting (e.g., as a phase shift andlor a power amplification)
is applied at the phased antenna array 106 in association with the k-th antenna element. The
complex weighting parameter Bk can be viewed as representing a phase and amplitude response
of the k-th antenna element. Hence, determining a signal response for each antenna element can
include determining phase and amplitude responses (or phase and amplitude parameters) for each
antenna element. The phase and amplitude responses defined by complex weighting pculinleter
Bk ale independent of the probe antenna 108 and the distance between (or the positions of) the
phased antenna array 106 and probe antenna 108. When a complex weigllting W,n (e g., as phase
shift andlor power amplification) is applied by the phased antenna array 106, the RF signal
radiated at the surface of the k-th antenna element can be equal to WL,kBI,X(w)I.n ihe case where
the phased antenna array 106 is ac1in.g as the receiving antenna, the signal response BkX(w) can
be viewed as the RF signal received at the surface of the k-th antenna element before any
weighting (e.g., as a phase shift andlor a power amplification) is appl~ed at the phased antenna
array 106 in association with the k-th antenna element.
[0072] In some instances, additional equations (similar to equations (1)) can be formulated, for
example, \vhen using multiple probe antennas 108. The multiple probe antennas 108 can be
associated with distinct locations (as discussed with respect to FIG. I), distinct polarizations (as
Atty. Dkt. No: 18CR047 (047141-131 1)
discussed with regard to FfG. 2A). distinct operating center frequencies (as discussed with regard
to FIG. 2B), or a combination thereof. In such instances, a separate set of equations (similar to
the set of equations (I)) can be formulated for each probe antenna 108. Accordingly, the antenna
testing control system 104 can solve multiple sets of equations and determine multiple signal
responses (or multiple phase and amplitude responses) for each antenna element. For example,
for a given antenna element, the antenna testing control system 104 can determine a signal
response for each center frequency andlor for each wave polarization (e.g., Horizontal and
vertical polarizations).
f0073j The method 300 can include determining one or more performance parameters of the
phased antenna array 106 using the determined signal responses (or the determined phase and
a~npl~tupdaer ameters) for the plurality of antenna elements 112. For instance, the antenna testing
control system 104 can use the detennined amplitudelphase response (or amplitude and phase
parameters) for each of the antenna elements 112 to determine a far field response of the phased
antenna array 106. The antenna testing control system 104 can use far field response of the
phased antenna array 106 to determine the performance parameters of the phased antenna array
106.
[0074] In some instances, the antenna testing control system 104 can use the phaselamplilude
responses of the antenna ele~nentsa nd an average individual antenna element radiation pattern
(e.g., representative of the radiation pattern of each antenna element 112 assuming similarly
behaving antenna elements 112) to determine the far field response (or radiation pattern) of the
phased antenna array 106. For instance, the far field response (or radiation pattern) of the phased
antenna array can be compu~ed as a weighted sum of the average individual antenna element
radiation pattern scaled by the phaselamplitude responses of the antenna elements 112.
[0075] Referring to FIG. 4, a block diagram illustrating an approach for determining the far
field response of the phased antcnna array 106 based on amplitudelphasc response (or amplitude
and phase parameters) for each of the antenna elements 112 is shown, according to inventive
concepts of this disclosure. By determining the phaselamplitude response for each antenna
Atty. Dkt. No: 18CR047 (047141-131 1)
element, thc antenna testing control system 104 can determine the electric (or magnetic) ficld
andlor electric current over a closed surface 402 around the phased antenna array. In particular,
the electric (or magnetic) field andlor electric cur~ento ver the closed surface 402 are non-zero
only over the portion 404 of the closed surface 402 that is facing (or ici ftont of) the antenna
elements 112 since electromagnetic waves radiated by the antenna elements 112 do not
propagate along the sides or the back of the phased antenna array 106.
[0076] According to the surface equivalence principle (or surface equivalence theorem), if the
fieldslcurrents are uniquely known over a closed surface (e.g. two of the electric field E,
magnetic field H, the magnetic flux density B vector, 01 the current density vector J) then the
fieldsicurrents everywhere inside or outside of the volume defined by the closed surface can be
uniquely identified or determined. Accordingly, the antenna testing control system 104 can. for
example, determine the electric field E and thc current density 3 vector based on the portion 404
of the closed surface 402 based on the determined amplitudelphase response for each antenna
element 1 12 of the phased anh-iriua,array 106. The antenna testing control system 104 can set the
electric field E and the current density J vector to zero on the rest of the closed surface 402. The
antenna testing control system 104 can then apply a Fourier transform to the determined
phaseiamplitude responses of the antenna elements 112 to determine a far field response of the
phased antenna array 106 according to the surface equivalence principle.
[0077] Referring to FIG. 5, examplc simulation results illustrating phaselampl~tude responses
of the antenna elements 112 of the phased antenna array 106 are shown, according to inventive
concepts of this disclowre. Each diamond shaped cell represents a corresponding antenna
element 1 12 of the pt~asrda rficnna array 106.
100781 Referring to FIG. 6, an examplc far field response of the phased antenna array 106
determined using the antenna elements' phaselamplitude responses shown in FIG. 5 is shown,
according to inventive concepts of this disclosure. The far field response shown in FIG. 6
represents a radiation pattern of the phased antenna array 106 along an azimuth angle range
between -100 and 100 degrees and an elevation angle range between -100 and 100 degrees.
Atty. Dkt. No: 18CR047 (047141-13 11)
[00791 When the phased antenna array 106 applies phase shifts (or time delays) andlor power
amplifications to the antenna elements 1 12 defined by the complex weighting parameters V,' (or
WE,,,), for k = 1. . . ., K, the antenna testing control system 104 can incorporate these co~nplex
weighting parameters into the phaseia~nplitude responses of the antenna elements 112, for
example, as VkBk (or WE,kBk)B. y determining the electric (or magnetic) fieldslcurrents over the
closed surface 402 based on the phaseia~nplituder esponses VkBk (or WLCkBkt)h,e antenna testing
control system 104 can use the Fourier transform to determine the far field response (or radiation
pattern) of the phased antenna array 106 when phase steered according to the complex weighting
parameters Vk (or WE,,), fork= I , ..., K.
(00801 Rased on the determined radiation patter of the phased antenna array 106, the antenna
testing control system 104 can determine one or Inore other performance parameters of the
phased antenna array including the phased antenna array gain (e.g., co-polarized gain and crosspolarized
gain), the co-polarized phased antenna array directivity (e.g., co-polarized directivity
and cross-polarized directivity), thephased antenna array beamwidth, thc radiated powel; the
cross-polarizalion discrimination, the antenna gain-to-noise-temperature, the error vector
magnitude, the adjacent channel power ratio, the pulse quality, one or more side lobe levels,
signal-to-noise ratio (SNR), or a combination thereof. For instance, the antenna testing control
system 104 can determine the peak phased antenna gain based on ihe peak value (at the main
lobe) of radiation pattern of the phased antenna array 106. To determine the co-polarized gain
and cross-polarized gain, two probe antennas 108 wit11 distinct polarizations (as discussed with
regard to FIG. 2A) can be used. One probe antenna 108 can be polarized similar the phased
antenna array 106 4e.g- bolh ,with ,!~orizonlal polarizations) and another probe antenna with
cross-polarization (e.g., vertical polarization when the phased antenna array has horizontal
polarization). The antenna testing control system 104 can determine a co-polarized far field
response and cross-polarized far field response of the phased antenna array 106. The antenna
testing control system 104 can determine the co-polarized gain using the determined co-polarized
far field response, and determine the cross-polarized gain using the determined cross-polarized
. . far field response of the phased antenna array.
Atty. Dkt. No: 18CR047 (047141-131 1)
[OOSl] The antenna testing control system 104 can determine the directivity as:
where F(B,cp) represents the far field response of the phased antenna array 106 along the
elevation angle B and azimuth angle cp. To determine the co-polarized directivity and the crosspolarized
directivity, the antenna testing control system 104 can evaluate equation (6) for the copolarized
far field response of the phased antenna array 106 and the cross-polarized far field
response of the phased antenna array 106 separately.
[0082] The antenna beamwidth of the phased antenna array 106 can be defined as the half
power beamwidth or the null to null beamwidth. The antenna testing control system 104 call
determine the angular separat~on in which the magnitude of the radiation pattern decreases by
50% (or 3 dB) from the peak of the main lobe in the case of the half power beamwidth. The
antenna testing control system 104 can determine ihe angular separation in which the magnitude
of the radiation pattern decreases zero from the peak of ihe main lobe in the case of the null to
null beamwidth. The antenna testing control system I04 call determine the radiated power as the
summation of the radiated powers of each of the antenna elements 112. The antenna testmg
control system 104 can also determine the cross-polarization discrimination, the antenna gain-tonoise-
temperature. the error vector magnitude, the adjacent channel power ratio, ilie pulse
quality, one or more side lobe levels, and the signal-to-noise ratio (SNR) using the determined
radiation pattern(s) of the phased antenna array andlor the determined phaselamplitude responses
(or phaselamplitude paramete~s)o f the phased antenna array 106.
[0083] Referring to FIG. 7, a flowchart illustrating another method 700 of testing phased
antenna arrays is shown, according to inventive concepts of this disclosure. In brief overview,
the method 700 can include positioning a phased antenna array and an antenna probe at relative
positions with respect to each other with one of them acting as a transmitting antenna and the
other acting as a receiving antenna (BLOCK 702), and applying to antenna elements of the
phased antenna array phase shifts to compensate for differences in signal propagation times
Atty. Dkt. No: 18CR047 (047141-131 1)
between the antenlia probe the antenna elements (BLOCK 704). The method 700 can include
causing the transmitting antenna to radiate an electromagnetic wave (BLOCK 706), receiving a
RF signal responsive to radiating the electromagnetic wave (BLOCK 708), and determining one
or more performance parameters of the phased antenna array using the receive d RF signal
(BLOCK 71 0).
[0084] The step 702 of method 700 can be similar to step 302 of method 300 described above.
The method 700 can also includc the a~itelinat esting control system causing the phased antenna
array 106 to apply to the antenna elements 112 phase shifts to compensate for d~ffere~iceins
signal propagation times between the antenna probe 108 and the antenna elements 112 (BLOCK
704). That is, the phase shifts are applied such that s~gnalstr ansmitted by the antenna elements
112 add up constructively at the receiving probe antenna 108, or signals received by the antenna
elements 112 add up constructively at the receiving phased antenna array 106. For instance, the
phase shift (or time delay) applied to each antenna element may be selected (e.g., by the antenna
testing control system 104q $of~wnipensatef or the propagating time between the probe antenna
and that antenna element 1 12. Applying phase shifts to the antenna eleme~lts 1 12 to compensate
for differences in signal propagation times between the antenna probe 108 and the antenna
elements 112 can cause the peak of the main lobe of the phased antenna array 106 to be aligned
with the probe antenna 108
[0085] The steps 706 and 708 of method 700 can be similar to the steps 304 and 308 of method
300 described above, except that the antenna testing control system 104 can cause the phased
antenna array 106 to increment (or modify) the phase shifts already applied to antenna elements
112 by a comlnonphase tfffsa, anapefform another transmission reception event. Such phase
offset can cause the peak of the main lobe (or the main lobe) of the phased antenna array 06 to
rotate by a predefined angle. The antenna testing control system 104 can repeat incrementing or
modifying the phase shifts (or time delays) applied to the antenna elements 112 by the same (or
another) phase offset value or (or offset calibration) to further tilt (or rotate) the radiation pattern
of the phased antenna array 106. For example, referring back to FIG. I, the offset calibrations
can cause the peak of the main lobe (or the main lobe) of the phased antenna array 106 to be
Atty. Dkt. No: 18CR047 (047141-1311)
aligned with a new position point 116 with each offset calibration. Such approach can allow for
determining the far tield response at various angles. I'or each receive RF signal (associated with
a corresponding offset calibration), the gain of the phased antenna array 106 (or the far field
I response) along an orientation angle (with respect to the peak of the main lobe of the radiation
pattern of the phased antenna array 106) associated with calibrated phases of the antenna
j
elements can be determined as
1
I where GA is the gain (or far field response) of the phased antenna array along the orientation
1 angle, GR is the gain (or far field response) along the same orientation angle of a reference (or
standard gain) antenna, PA is received power of the phased antenna array 106, and P, is the
received power of the reference antenna. The gain CR and the power and P, for each orientation
angle can be known to (or accessible to) the antenna testing control system 104, and the power
PA f the phased antenna array 106 can be computed for each phase calibration (or orientation of
the radiation pattern of the phased antenna array 106) based on, for example, the corresponding
received (or transmitted) signal by the phased antenna array. Accordingly, the antenna testing
co~ltrols ystem 104 sample the radiation pattern of the phased antenna array 106 by applying the
phase offset calibrations.
[0086] Using the measured samples of the radiation pattern (or far field response) of the
phased antenna array 106, ihe antenna testing control system 104 can determine one or more
perforrnallce parameters of the phased antenna array 106. For example, the antenna testing
' .. ,
control system 104 can determine the performance parameters including the phased antenna
array gain (e.g., co-polarized gain and cross-polarized gain), the co-polarized phased antenna
array directivity (e.g., co-polarized directivity and cross-polarized directivity), the phased
antenna array beamwidth, the radiated power, the cross-polarization discrimination, the antenna
gain-to-noise-temperature, the error vector magnitude, the adjacent channel power ratio, the
pulse quality, one or more side lobe levels, signal-to-noise ratio (SNR), or a combination thereof,
Atty. Dkt. No: 18CR047 (047141-13 11)
using the measured radiation pattern (or samples thereof) as discussed above with regard to FIG.
3. By applying the phase offset calibrations, the antenna testing control system 104 can
determine the far field response of the phased antenna array 106 without necessarily scanning the
beam anywhere near the probe antenna 108.
[0087] Referring to I'IG. 8, a block diagram of a phased antenna array testing system 800 is
shown, according to inventive concepts of this disclosure. While conventional testing systems
typically employ a network analyzer which is considered as a complex and expensive equipment,
the system 800 can include a first low noise block (LNB) down-converter 802 (e.g., a circuit) to
down-convert signals received kom phased antenna array 804 to an intermediate frequency. The
system 800 can include a first DVB-T USB device 806 and a computing device 808. 7 he first
DVB-T USB device 806 can couple the first (LNB) down-converter 802 to the computing device
808.
[0088] The computing device 808 can include, for example, a laptop, a desktop, a hardware
server, a tablet, a mobile device, or a printed circuil board. The computing device 808 can be
configured (e.g., through executable software instructions) to perform tasks and processes
described above as performed by the antenna testing control system 104, such as controlling and
monitoring phase steering of the phased antenna array, processing receive RF signals,
determining performance parameters of the phased antenna array, or a combination thereof. The
computing dev~ce 808 can be communicatively coupled through a second DVB-T USB device
810 and a second low noise blocli (1,NB) down-converter 812 (e.g., a circuit) to the probe
antenna 814. I he second low noise block (LNB) down-converter 812 can down-convert receive
s~gnalso btained by the probe snteima 814 to an intermediate frequency.
[0089] The system 800 can include a signal generator circuit 816 for generating, for example,
baseband transmit RF signals. The signal generator circuit 816 can be communicatively coupled
to the computing device 808, for example, to receive instructions from the computing device 808
andlor provide copies of generated baseband transmit RF signals lo the computing device 808.
The signal generator circuit (or device) 816 can be communicatively coupled to the transmitting '
Atty. Dkt. No: 18CR047 (047141-1311)
antenna (phased antenna array 804 or the probe antenna 814 through an up-converter block (or
circuit) 8 18. The up-converter block 816 can up-convert signals provided by the signal generator
circuit 816 to an intermediate (or high) frequency, and provided the up-converted signals to the
transmitting antenna.
[0090] Referring to FIG. 9, a block diagram of another phased antenna array testing system
900 is shown, according to inventive concepts of this disclosure. The system 900 can be similar
to the system 800 except that the computing device 808 in system 800 is replaced with a USR
hub 902 that is communicatively coupled the phased antenna array 904, and the phased antenna
array includes a processor 906 that is configured to perform the tasks or operating performed by
the computing device 808 in system 800. Specifically, the processor 906 can be configured (e.g.,
through executable software instructions) to perforin tasks and processes described above as
performed by the antenna testing control system 104, such as controlling and ~nonitoringp hase
steering of the phased antenna array 904, processing receive RF signals, determining
performance para~netemotfh e1pI1~sed.*antennma ay 904, or a combination thereof.
[0091] The construction and arrangement of the systems and methods are described herein as
illustrative examples and are not to be construed as limiting. Although only a few embodiments
have been described in detail in this disclosure, many modifications are possible (e.g., variations
in sizes, dimensions, structures, shapes and proportions of the various elements, values of
parameters, mounting arrangements, use of materials, colors, orientations). For example, the
position of elements may be reversed or otherwise varied and the nature or number of discrete
elements or positions may be altered or varied. Accordingly, all such modifications are intended
to be included within The sscope'cifiheinventive concepts disclosed herein. The order or sequence
of any operational flow or method of operations may be varied or re-sequenced according to
alternative embodiments. Other substitutions, nlodifications, changes, and omissions may be
made in the design, operating conditions and arrangement of the exemplary embodiments
without departing from the broad scope of the inventive concepts disclosed herein.

CLAIMS
WIHAT IS CLAIMED IS:
1. A method of testing phased antenna arrays, the method comprising:
positioning a phased antenna array including a plurality of antelilia elements and a probe
antenna at relative positions with respect to each other, either ihe phased antenna array acting as
a transmitting antenna and tlie probe antenna acting as a receiving antenna, or the probe antenna
acting as the transmitting antelma and the phased antenna array acting as the receiving antenna;
causing the transmitting antenna to radiate a plurality of electromagnetic waves
sequentially;
causing the phased antenna array to operate, during transmission of each electrolnagnetic
wave of the plurality of electromagnetic waves, according to a corresponding configuration
scheme, the corresponding configuralion scheme defining a respective set of antenna elements
that are active during the transmission of the electromagnetic wave or a respective phase coding
,+.,~.
scheme applied to the plurality of antenna elements during the trans~nissio~oi f the
electromagnetic wave;
receiving, by the receiving antenna, responsive to each radiated electromagnetic wave, a
corresponding receive radio frequency (RF) signal;
determining, for each antenna element of the plurality of antenna elements;
corresponding amplitude and phase parameters using the receive RF signals; and
determining one or more performance parameters of the phased antenna array using the
determined amplitude and phase parameters for the plurality of antenna elements.
,,',
2. The method of claim 1 comprising:
positioning the probe antenna at a near field location relative to the phased antenna array.
3. The method of claim 1, wherein the one or more performance parameters include at least one
of:
co-polarized antenna gain;
Atty. Dkt. No: 18CR047 (047141-131 1)
cross-polarized antenna gain
co-polarized antenna directivity;
cross-polarized antenna directivity:
antenna beam width;
radiated power;
cross-polarization discrimination;
antenna gai11-to-noise-temperature;
en-or vector magnitude;
adjacent channel power ratio;
pulse quality;
one or more side lobe levels; and
signal-to-noise ratio (SNR).
4. The method of claim 1 comprising:
deterlnining a far field response of the phased antenna array using the determined
amplitude and phasc parameters for each ofthe plurality of antenna elements.
5. The method of claim 1, wherein causing the phased antenna array to operate according to a
corresponding configuration scheme includes:
activating the plurality of antenna elements one at a time such that each antenna element
is activated to:
transmit an electromagnetic wave of the plurality of electromagnetic waves and
the probe anconnareceiving, responsive to transmission of the electromagnetic wave by
the antenna element, the corresponding receive RF signal; or
receive, responsive to transmission of an electromagnetic wave of the plurality of
electromagnetic waves by the probe antenna, the corresponding receive RF signal.
Atty. Dkt. No: 1 SCR047 (047 I41 - I 3 11)
6. The method of claim 5 comprising:
determining, for each antenna element of the plurality of antenna elements, the
corresponding amplitude and phase parameters using the corresponding receive RF signal
received during activation of the antenna element.
7. The method of claim 1, wherein causing the phased antenna array to operate according to a
corresponding configuration scheme includes:
phase steering the plurality of antenna elements, during transmission of each
electro~nagneticw ave of the plurality of electromagnetic waves, according to a respective phase
coding scheme, each phase coding scheme defining a corresponding set of phase shifts or a
corresponding set of time delays applied to the plurality of antenna elements during transmission
of a corresponding electromagnetic wave of the plurality of electromagnetic waves.
8. The method of claim 7 comprising:
transmitting each electro~nagneticw ave of the plurality of electromagnetic waves by the
plurality of antenna eleinents phase steered according to the corresponding set of phase shifts or
the 'orresponding set of time delays, the antenna probe receiving, responsive to transmission of
the electromagnetic wave by the plurality of antenna elemenis, the corresponding receive RF
signal; or
transmitting each electromagnetic wave of the plurality of electromagnetic waves by the
probe antenna and the phased antenna array receiving, responsive to transmission of the
electromagnetic wave by the antenna probe, the corresponding receive RF signal.
, , ,, .
9. The method of claim 1, wherein causing the phased antenna array to operate according to a
corresponding co~ifigurations cheme includes:
phase steering a group of active antenna elements of the plurality of antenna elements,
during transmission of each electromagnetic wave of the plurality of electromagnetic waves,
according to a respective phase coding scheme.
Atty. Dkt. No: 18CR047 (047141-131 1)
10. I he method of claim I further comprising modifying the relative positions by causing the
antenna probe or the phased antenna array to move along a predefined path during transmission
of the plurality of electromagnetic waves.
1 1. The method of claim 1 comprising:
positioning at least two antenna probes with distinct polarizations; or
positioning a single dual polarized antenna probe.
12. The method ofclaim 1 comprising:
positioning a plurality of probe antennas operating at different center frequencies at
various positions relative to the phased antenna array.
13. The method of claim 1 further comprising:
applying a predefined phase offset to the plurality of antenna elements; and
receiving one or more additional receive signals at an anglc offset with respect to a main
lobe of the receiving antenna.
14. A method of testing phased antenna arrays, the method comprising:
positioning a phased antenna array including a plurality of antenna elements and a probe
antenna at relative positions with respect to each other, either the phased antenna array acting as
a transmitting antenna and the probe antenna acting as a receiving antenna, or the probe antenna
actiug as the transmitting antenna and the phased antenna array acting as the receiving antenna;
applying, to eaoh anton~na.elcrnenot f the plurality of antenna elements, a corresponding
phase shift or a corresponding time delay to compensate for differences in signal propagation
times between the probe antenna and each of the plurality of antenna elements;
causing the transmitting antenna to radiate an electromagnetic wave;
receiving, by the receiving antenna, a receive radio frequency (RF) signal responsive to
radiating the electrornagnctic wave; and
Atty. Dkt. No: 18CR047 (047141-131 1)
determining one or more performance parameters of the phased antenna array using the
receive RF signal.
15. The method of claim 14 comprising:
positioning the probe antenna at a near field location relative to the phased antenna array
16. The method of claim 14, wherein the one or more performance parameters include at least
one of:
co-polarized antenna gain;
cross-polarized antenna gain;
co-polarized antenna directivity;
cross-polarized antenna directivity;
antenna heamwidth:
radiated power;
cross-polarization discrimination;
antenna gain-to-noise-temperature;
error vector magnitude;
adjacent channel power ratio;
pulse quality;
one or more side lobe levels; and
signal-to-noise ratio (SNR).
17. The method of claim 4$-cornprisii?g:
positioning at least two antenna probes with distinct polarizations: or
positioning a single dual polarized antenna probe.
18. The method of claim 14 comprising:
positioning a plurality of probe antennas operating at different center frequencies at one
or more positions relative to the phased antenna array.
Atty. Dlt. No: 18CR047 (047141-131 1)
19. A system for testing phased antenna arrays, the system comprising:
a signal generator circuit, com~nunicativelyc oupled to a phased antenna array including a
plurality of antenna elements or a probe antenna positioned at a relative position with respect to
the phased antenna array, to generate one or more transmit radio frequency (RF) signals for
transmission by the phased antenna array or the probe antenna, either the phased antenna array
acting as a transmitting antenna and the antenna probe acting as a receiving antenna, or the
antenna probe acting as the transmitting antenna and the phased antenna array acting as the
rec,eiving antenna; and
a processor communicatively coupled to the signal generator circuif the phased antenna
array, and the probe antenna, the processor configured to:
cause the transmitting antenna to sequentially radiate a plurality of
electro~nagneticw aves associated with the one or more transmit RF signals;
cause the phased antenna array to operate, during transmission of each
electromagnetic wave of the plurality of electromagnetic waves, according to a
corresponding configuralion scheme, the corresponding configuration scheme defining a
respective set of antenna elen~cnts that are active during the transmission of the
electromagnetic wave or a respective phase coding scheme applied to the plurality of
antenna elements during the transmission of the electromagnetic wave;
obtain, from the receiving antenna, responsive to each radiated electromagnetic
wave, a coi~espondingre ceive RF signal, the receive RF signal received by the receiving
antenna responsive to the radiated electromagnetic wave;
determiiie;.,far cwh antenna element of the plurality of antenna elements,
corresponding amplitude and phase parameters using the receive RF signals; and
determine one or more perfor:-lance parameters of the phased antenna array using
the determined amplitude and phase palameters for the plurality of antenna elements.
20. The system of claim 19, wherein the processor is embedded within the phased antenna array.