Description:TECHNICAL FIELD
[0001] The present disclosure relates, in general, to broadband phased array antenna systems, and more specifically, relates to a system and hybrid method of efficient transmission of electromagnetic energy suited for wideband compact radar, electronic warfare and communication systems.

BACKGROUND
[0002] Any phased array antenna system requires pre-determined phases applied to individual radiators to be changed as per the scanning requirement. Apart from the phase control, amplitude control, gain using a low noise amplifier during receive and power amplifier during transmission might be required. The power amplifier and the LNA should preferably be at the element level to ensure feasible heat management due to the low wattage of the power amplifier during transmission and low noise during the reception. Therefore, a phased array antenna system requires the above electronic module at the radiating element level.
[0003] Conventional methods for phased array systems utilize either the “tile” or “brick” configuration for integrating the antenna with the electronic modules. R.J Mailloux discussed the configuration and its advantages and disadvantages. Tile based configuration provides a very low profile phased array system but suffers from space limitation for electronic modules and thermal management. Brick based configuration provides enough space for electronic modules and efficient thermal management but suffers from higher profile.
[0004] Conventional medium of implementation of radiating structure for tile configuration are printed patch and its variants. Such radiating structures suffer from bandwidth limitations. Whereas for the brick configuration, slotted waveguide and printed dipoles are conventional radiating structures. The slotted waveguide brick again suffers from bandwidth limitation. The printed dipoles have wide band but suffers from higher profile in phased array systems. Feed structures for phased arrays can be divided into two levels - electronic modules and power combiner/splitters. Printed transmission medium like micro-strip, strip-line etc., are generally used for electronic modules as these modules are mostly RFIC. Both printed and waveguide-based transmission medium may be used for power combiner/splitter. Waveguide based transmission provides lower loss compared to printed medium based transmission. Printed medium based transmission is simpler to implement as electronic modules (RFICs) can be made in a single printed circuit board. However, for larger arrays at higher frequency the feed loss (power splitter/combiner) becomes a hindrance for efficient phased array antenna system. Therefore, phased array antenna system prefers a hybrid medium of transmission where feed section have waveguide-based transmission as first level (power combiner/splitter) and printed medium of transmission as second level (RFICs).
[0005] An example of such devices is recited in a patent US11462837B2 that provides such a hybrid method of waveguide-based level two feed structure and printed based level one feed structure along with radiation element. Another example is recited in a patent US2022320750A1 that provides a phased array system with impedance transformation unit and MEMS based phase shifter integrated with a printed radiating element in a brick based configuration. Yet another example is recited in a literature Phased Array Antenna Element with Embedded Cavity and MMIC using Direct Digital Manufacturing”, Merve Kacar, Jing Wang, Gokhan Mumcu that reports a printed phased array antenna with an integrated phase shifter in tile based configuration. However, the existing device suffers from limitations that include low gain and low efficiency.
[0006] Therefore, it is desired to overcome the drawbacks, shortcomings, and limitations associated with existing solutions, and develop a phased array antenna system having high gain,high efficiency,wide scanning, wide bandwidth, ease of integration with electronic modules,integrated calibration provisions and compact form-factor.

OBJECTS OF THE PRESENT DISCLOSURE
[0007] An object of the present disclosure relates,in general, to broadband phased array antenna systems, and more specifically, relates to a system and hybrid method of efficient transmission of electromagnetic energy suited for wideband compact radar, electronic warfare and communication systems.
[0008] Another object of the present disclosure is to provide a wide band phased array antenna system that is disclosed with a wide band of operation along with high gain and efficiency.
[0009] Another object of the present disclosure is to provide a system that creates a phased array antenna using a hybrid mode of transmission.
[0010] Another object of the present disclosure is to provide a system having an efficient three levels of energy transfer.
[0011] Another object of the present disclosure is to provide a system having electromagnetic energy tapping mechanism using a trapezoid-shaped printed structure.
[0012] Another object of the present disclosure is to provide a mechanism wherein the RF frontend is concealed within the radiating section.
[0013] Yet another object of the present disclosure is to provide a calibration provision integrated within the antenna system.

SUMMARY
[0014] The present disclosure relates to, in general, to broadband phased array antenna system, and more specifically, relates to a system and hybrid method of efficient transmission of electromagnetic energy suited for wideband compact radar, electronic warfare and communication systems.
[0015] The present disclosure relates to a wideband phased array antenna system that includes a hybrid mechanism to transfer guided electromagnetic energy to radiated electromagnetic energy using three levels of energy transfer. The three levels include a first level that transfers guided electromagnetic energy from a coaxial connector to a contactless ridge guide, wherein the electromagnetic energy flows in the horizontal plane. A second level transfers the guided electromagnetic energy from the contactless ridge guide to concealed RF front-end strip line, wherein the electromagnetic energy flows in the vertical plane. A third level transfers the guided electromagnetic energy from the concealed RF front end of strip-line-based architecture to flared metal radiating section, where the electromagnetic energy radiates into free space.
[0016] Various objects, features, aspects, and advantages of the inventive subject matter will become more apparent from the following detailed description of preferred embodiments, along with the accompanying drawing figures in which like numerals represent like components.

BRIEF DESCRIPTION OF THE DRAWINGS
[0017] The following drawings form part of the present specification and are included to further illustrate aspects of the present disclosure. The disclosure may be better understood by reference to the drawings in combination with the detailed description of the specific embodiments presented herein.
[0018] FIG. 1A illustrates an exemplary isometric view of a wideband phased array antenna system, in accordance with an embodiment of the present disclosure.
[0019] FIG. 1B illustrates an exemplary side view of a wideband phased array antenna system, in accordance with an embodiment of the present disclosure.
[0020] FIG. 1C illustrates an exemplary functional component of the second section of the wideband phased array antenna system, in accordance with an embodiment of the present disclosure.
[0021] FIG. 1D illustrates an exemplary side view of the second section, in accordance with an embodiment of the present disclosure.
[0022] FIG. 2 illustrates an exemplary view of the concealed RF front-end PCB of the wideband phased array antenna system, in accordance with an embodiment of the present disclosure.
[0023] FIG. 3 illustrates an exemplary mechanism of calibration of the wide band phased array antenna system, in accordance with an embodiment of the present disclosure.
[0024] FIG. 4 illustrates an exemplary flow chart of a method of creating a wide-band phased array, in accordance with an embodiment of the present disclosure.

DETAILED DESCRIPTION
[0025] The following is a detailed description of embodiments of the disclosure depicted in the accompanying drawings. The embodiments are in such detail as to clearly communicate the disclosure. If the specification states a component or feature “may”, “can”, “could”, or “might” be included or have a characteristic, that particular component or feature is not required to be included or have the characteristic.
[0026] As used in the description herein and throughout the claims that follow, the meaning of “a,” “an,” and “the” includes plural reference unless the context clearly dictates otherwise. Also, as used in the description herein, the meaning of “in” includes “in” and “on” unless the context clearly dictates otherwise.
[0027] The present disclosure relates, in general, to broadband phased array antenna systems, and more specifically, relates to a system and hybrid method of efficient transmission of electromagnetic energy suited for wideband compact radar, electronic warfare and communication systems.
[0028] The present disclosure relates to a method of creating a wideband phased array antenna using a hybrid feeding technique with good electromagnetic performance in a compact footprint is disclosed. The disclosed antenna uses a hybrid method of feeding a combination of concealed printed strip-line-based RF frontend interconnecting phase shifter and an antenna element and a contactless metal ridge low-loss power divider. Electromagnetic waves in the feed section of the disclosed antenna array traverse from a contactless ridge guide i.e., metal structures to a concealed RF front end i.e., printed structures, where beam steering, combining etc are performed and finally the electromagnetic energy traverses to the wide band antenna element constructed of a flared metal radiating section. The disclosure also provides a calibration mechanism in which printed structures are used in between the radiating structures. The present disclosure can be described in enabling detail in the following examples, which may represent more than one embodiment of the present disclosure.
[0029] The advantages achieved by the system of the present disclosure can be clear from the embodiments provided herein. The disclosure provides a method of creating such hybrid antenna arrays using a simple fabrication mechanism. This unique mechanism ensures that a wideband phased array can be formed using low loss and compact form-factor. The description of terms and features related to the present disclosure shall be clear from the embodiments that are illustrated and described; however, the invention is not limited to these embodiments only. Numerous modifications, changes, variations, substitutions, and equivalents of the embodiments are possible within the scope of the present disclosure. Additionally, the invention can include other embodiments that are within the scope of the claims but are not described in detail with respect to the following description.
[0030] FIG. 1A illustrates an exemplary isometric view of a wideband phased array antenna system, in accordance with an embodiment of the present disclosure.
[0031] Referring to FIG. 1A, wideband phased array antenna system 100 of the present invention is disclosed. The wideband phased array antenna system 100 can include five primary sections (102, 104, 202, 302) shown in FIG. 1A to FIG. 3 respectively. Electromagnetic energy experiences three levels of hybrid transformation as it passes through the above-mentioned primary sections (102, 104, 202, 302).
[0032] The proposed method of creating a wide band phased array using the hybrid mechanism of transfer of guided electromagnetic energy to radiated electromagnetic energy using three levels of energy transfer and concealed phase shifting along with other electronic elements. The three levels of energy transfer are as follows:
[0033] The first level transfers guided electromagnetic energy from a coaxial connection to a contactless ridge guide where the electromagnetic energy flows in the horizontal plane. The second level transfers guided electromagnetic energy from the contactless ridge guide to concealed RF front-end strip line-based guided medium where the electromagnetic energy flows in the vertical plane. The third level transfers guided electromagnetic energy from concealed RF front-end strip line to flared metal radiating section where the electromagnetic energy radiates into free space.
[0034] In transmit mode of operation, the electromagnetic energy enters the wideband phased array antenna system 100 through the coaxial connector 106 shown in FIG. 1B. The electromagnetic energy flows to the second section 104 after encountering a mode conversion. The mode conversion from TEM of coaxial connector 106 to Quasi TEM of ridge guide 110 is facilitated by a circular ring-based mode converter 108 as shown in FIG. 1C.
[0035] FIG. 1C illustrates an exemplary functional component of the second section of the wideband phased array antenna system, in accordance with an embodiment of the present disclosure. The second section 104 of the wide band phased array antenna system 100 is the contact less ridge guide 110 encased within an array of rectangular blocks 112.The array of rectangular blocks 112 ensures the efficient energy flow within the ridge guide 110 and minimal along the gaps S shown in FIG. 1B. The second section 104 can contain four cylinders 116 used as a mounting structure as well as ensuring appropriate gaps for the proper functioning of the array of rectangular blocks 112. The mechanism of the contactless guide facilitates ease of fabrication and ensures a low loss energy transfer.
[0036] The system can include the circular ring-based mode converter 108 that converts the transverse electric and magnetic (TEM) mode of the coaxial connector 106 to the quasi-TEM mode of the contactless ridge guide 110. The contactless ridge guide 110 with full metal configuration as the first level of transfer of electromagnetic energy and distribute the energy. The distributed energy flows to the concealed RF front end 202 by a combination of an electromagnetic energy tapping provision 114. The distributed energy is tapped by a trapezoid-shaped PCB 204 serving as a tapping probe into the concealed RF front end 202.
[0037] The tapped energy is processed with desired amplification, and phase shift to obtain beam steering. The energy transfer occurs with the RF front-end beam processing like phase shift, attenuation in the second level of transfer and incurring low loss and compactness during the overall three levels of transfer. The phase shifting element and associated electronic modules are concealed along with the strip-line between the flared metal radiating section 102 to construct the antenna element.
[0038] FIG. 2 illustrates an exemplary view of the RF front-end PCB of the wideband phased array antenna system, in accordance with an embodiment of the present disclosure.
[0039] The second section 104 which uses the ridge guide 110 in quasi-TEM mode performs the first level of electromagnetic energy transfer. This section transfers the electromagnetic energy to a plurality of elements. The distributed energy flows to the third section 202 (also referred to as RF front end PCB 202, herein) shown in FIG. 2 by a combination of a novel electromagnetic energy tapping provision 114 along with a trapezoid-shaped PCB 204.The mechanism forms the second level of hybrid transformation of the wide band phased array antenna system 100.
[0040] The trapezoid-shaped PCB 204 serves as a tapping probe to tap the distributed energy from the tapping provision 114 to the concealed RF front end 202. The concealed RF front end 202 uses a strip-line-based architecture which is concealed within the metallic phased array antenna element 102 (also referred to as first section 102). The electromagnetic energy inside the strip-line encounters electronic modules 206 which ensure proper phase, amplitude and gain as required by the wideband phased array antenna system 100. The electromagnetic energy after desired amplification and phase shift flow through slot line 208, which facilities the conversion of guided electromagnetic energy to radiated electromagnetic energy as it flows through the all-metal flared radiation section 102. Provisions have been made in the wide band phased array system 100 to reduce the edge effects by termination 210 of the edge elements in the phased array.
[0041] The electromagnetic energy flowing from the concealed RF front end 202 to the flared radiating section 102 forms the third level of hybrid energy transformation. Section 102 is used as a split block (124, 126) to ensure RF front end PCB 202 is concealed inside it. Section 102 further contains a groove structure 128 to ensure air strip-line formation facilitating low-loss energy transformation.
[0042] FIG. 1D illustrates an exemplary side view of the second section, in accordance with an embodiment of the present disclosure. As per FIG. 1D, the height H can be optimally chosen based on bandwidth and profile. If H is chosen on the higher side the bandwidth may be higher at the cost of a higher profile. However, if H is chosen on the lower side the bandwidth may be lower but lower profile. Therefore, H should be chosen optimally based on the application. The section 102 also contains vertical slot 122 and horizontal slot 120, which provides a smoother transition from the guided electromagnetic energy mode to radiated electromagnetic energy mode. As seen in FIG. 1D rectangular PCB projections 118 which house the trapezoid-shaped probes 204 facilitate the second level of energy transformation.
[0043] FIG. 2 illustrates an exemplary view of the RF front-end PCB of the wideband phased array antenna system, in accordance with an embodiment of the present disclosure. The third level transfers guided electromagnetic energy from concealed RF front-end strip line to flared metal radiating section, where the electromagnetic energy radiates into free space.
[0044] FIG. 3 exemplifies a mechanism of calibration of the wide band phased array antenna system 100. The fourth section 302 can include a PCB with micro-strip traces (304-1 to 304-3) intended to couple the power radiated by the radiating flare section 102.The traces are to optimally chosen by varying their width to couple the necessary power without degrading the patterns or reducing efficiency.
[0045] Thus, the present invention overcomes the drawbacks, shortcomings, and limitations associated with existing solutions, and provides a wide-band phased array antenna system that is disclosed with a wide band of operation along with high gain and efficiency. The system creates a phased array antenna using a hybrid mode of transmission. The system has an efficient three levels of energy transfer, the system having electromagnetic energy tapping mechanism using a trapezoid shaped printed structure. The present disclosure provides a mechanism wherein RF frontend is concealed within the radiating section and a calibration provision is integrated within the antenna system.
[0046] FIG. 4 illustrates an exemplary flow chart of a method of creating a wide-band phased array, in accordance with an embodiment of the present disclosure.
[0047] Referring to FIG. 4, the method 400 includes at block 402, providing a hybrid mechanism to transfer guided electromagnetic energy to radiated electromagnetic energy using three levels of energy transfer.
[0048] At block 404, transferring, at the first level, the guided electromagnetic energy from a coaxial connector (106) to a contactless ridge guide (110), wherein the electromagnetic energy flows in the horizontal plane.
[0049] At block 406, transferring, at a second level, the guided electromagnetic energy from the contactless ridge guide (110) to concealed RF front end strip line (202), wherein the electromagnetic energy flows in the vertical plane.
[0050] At block 408, transferring, at a third level, the guided electromagnetic energy from the concealed RF front end strip line (202) to flared metal radiating section, wherein the electromagnetic energy radiates into free space.
[0051] It will be apparent to those skilled in the art that the system 100 of the disclosure may be provided using some or all of the mentioned features and components without departing from the scope of the present disclosure. While various embodiments of the present disclosure have been illustrated and described herein, it will be clear that the disclosure is not limited to these embodiments only. Numerous modifications, changes, variations, substitutions, and equivalents will be apparent to those skilled in the art, without departing from the spirit and scope of the disclosure, as described in the claims.
ADVANTAGES OF THE PRESENT INVENTION
[0052] The present disclosure provides a wide band phased array antenna system that is disclosed with wide band of operation along with high gain and efficiency.
[0053] The present disclosure provides a system that creates a phased array antenna using a hybrid mode of transmission.
[0054] Another object of the present disclosure is to provide a system having an efficient three levels of energy transfer which in turn ensures low loss and high efiiciency and thereby high gain.
, Claims:1. A wideband phased array antenna system (100) comprising:
a hybrid mechanism to transfer guided electromagnetic energy to radiated electromagnetic energy using three levels of energy transfer, the three levels comprising:
a first level that transfers guided electromagnetic energy from a coaxial connector (106) to a contactless ridge guide (110), wherein the electromagnetic energy flows in the horizontal plane;
a second level transfers the guided electromagnetic energy from the contactless ridge guide (110) to concealed RF front-end (202)of strip-line-based architecture, wherein the electromagnetic energy flows in the vertical plane; and
a third level transfers the guided electromagnetic energy from the concealed RF front end (202) to flared metal radiating section (102), wherein the electromagnetic energy radiates into free space.
2. The system as claimed in claim 1, wherein the system comprises a circular ring-based mode convertor (108) that converts the transverse electric and magnetic (TEM) mode of the coaxial connector (106) to quasi-TEM mode of the contactless ridge guide (110).
3. The system as claimed in claim 1, wherein the contactless ridge guide (110) with full metal configuration as the first level of transfer of electromagnetic energy and distribute the energy.
4. The system as claimed in claim 1, wherein the distributed energy flows to the concealed RF front end (202) by a combination of an electromagnetic energy tapping provision (114).
5. The system as claimed in claim 1, wherein the distributed energy is tapped by a trapezoid-shaped PCB (204) serving as a tapping probe into the concealed RF front end (202).
6. The system as claimed in claim 1, wherein the tapped energy is processed with desired amplification, phase shift to obtain beam steering.
7. The system as claimed in claim 1, wherein the energy transfer occurs with the RF front-end beam processing like phase shift, attenuation in the second level of transfer and incurring low loss and compactness during the overall three levels of transfer.
8. The system as claimed in claim 1, wherein the phase shifting element and associated electronic modules are concealed along with the strip-line between the flared metal radiating section (102) to construct the antenna element.
9. A method (400) of creating a wide band phased array, the method comprising:
providing (402) a hybrid mechanism to transfer guided electromagnetic energy to radiated electromagnetic energy using three levels of energy transfer;
transferring (404), at a first level, the guided electromagnetic energy from a coaxial connector (106) to a contactless ridge guide (110), wherein the electromagnetic energy flows in the horizontal plane;
transferring (406), at a second level, the guided electromagnetic energy from the contactless ridge guide (110) to concealed RF front end (202) of strip-line-based architecture, wherein the electromagnetic energy flows in the vertical plane; and
transferring (408), at a third level, the guided electromagnetic energy from the concealed RF front end to flared metal radiating section, wherein the electromagnetic energy radiates into free space.