1. A MIMO radar signal processing device comprising:
a plurality of transmission signal generating units to generate transmission
signals different from each other and output the generated transmission signals to
5 corresponding transmission antennas;
a plurality of matched filter banks, each receiving a reception signal from a
reception antenna corresponding to each of a plurality of reception antennas that capture
reflected waves obtained by transmission waves transmitted from the transmission
antennas, reaching an object and being reflected as arrival waves and transmission
10 signals from the plurality of transmission signal generating units, and outputting
matched filter outputs serving as vector elements of reception signal vectors using the
transmission signals from the plurality of transmission signal generating units as a
replica of a matched filter; and
a bidirectional angle measuring unit to obtain a bidirectional measured angle
15 value constituted by a direction-of-departure and a direction-of-arrival in a reception
signal vector of interest corresponding to a range Doppler cell given in target detection
processing among reception signal vectors for matched filter outputs from the plurality
of matched filter banks.
20 2. The MIMO radar signal processing device according to claim 1, wherein the
bidirectional measured angle value by the bidirectional angle measuring unit is obtained
by obtaining a direction-of-departure and a direction-of-arrival at which a directional
spectrum obtained using a transmission array steering vector related to the transmission
signal and a reception array steering vector related to the reception signal as variables
25 indicates a maximum value as a direction-of-departure and a direction-of-arrival
constituting the bidirectional measured angle value in the reception signal vector of
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interest.
3. The MIMO radar signal processing device according to claim 1, wherein the
bidirectional measured angle value by the bidirectional angle measuring unit is obtained
5 by obtaining a direction-of-departure and a direction-of-arrival at which a directional
spectrum obtained using a direction-of-departure and a direction-of-arrival constituting
the bidirectional measured angle value in the reception signal vector of interest as
variables indicates a maximum value, as a direction-of-departure and a direction-ofarrival constituting a bidirectional measured angle value in the reception signal vector of
10 interest.
4. The MIMO radar signal processing device according to claim 1, wherein when
there is a directional spectrum indicating a plurality of local maximum points in a
directional spectrum obtained by using a direction-of-departure and a direction-of15 arrival constituting the bidirectional measured angle value in the reception signal vector
of interest as variables, the bidirectional measured angle value by the bidirectional angle
measuring unit is obtained by calculating a difference between a direction-of-departure
and a direction-of-arrival corresponding to each of directional spectra indicating a
plurality of local maximum points, and obtaining a direction-of-departure and a
20 direction-of-arrival corresponding to a directional spectrum in which the difference
between the direction-of-departure and the direction-of-arrival is minimum, as a
direction-of-departure and a direction-of-arrival constituting the bidirectional measured
angle value in the reception signal vector of interest.
25 5. The MIMO radar signal processing device according to claim 1, wherein the
bidirectional measured angle value by the bidirectional angle measuring unit is obtained
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by obtaining a directional spectrum with a multipath steering vector as a variable, the
multipath steering vector being a sum of a virtual array steering vector corresponding to
a direction-of-departure and a direction-of-arrival different from each other and a virtual
array steering vector obtained by switching a direction-of-departure and a direction-of5 arrival with respect to the virtual array steering vector when the direction-of-departure
and the direction-of-arrival constituting the bidirectional measured angle value in the
reception signal vector of interest as variables are different from each other, obtaining a
directional spectrum with a virtual array steering vector corresponding to the same
direction-of-departure and the direction-of-arrival when the direction-of-departure and
10 the direction-of-arrival constituting the bidirectional measured angle value in the
reception signal vector of interest as variables are the same, and obtaining the directionof-departure and the direction-of-arrival at which the obtained directional spectrum has
a maximum value as the direction-of-departure and the direction-of-arrival constituting
the bidirectional measured angle value in the reception signal vector of interest.
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6. The MIMO radar signal processing device according to any one of claims 1 to
5, further comprising a propagation mode distinguishing unit to distinguish, by the
bidirectional side angle value, whether a propagation mode of a reception signal vector
of interest for the bidirectional measured angle value calculated by the bidirectional
20 angle measuring unit is a direct propagation mode or a multipath propagation mode.
7. The MIMO radar signal processing device according to claim 6, wherein the
propagation mode distinguishing unit compares a value of a difference between a
direction-of-departure and a direction-of-arrival constituting the bidirectional measured
25 angle value obtained by the bidirectional angle measuring unit with a threshold,
distinguishes the propagation mode as a direct propagation mode when the value of the
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difference is equal to or less than the threshold, and distinguishes the propagation mode
as a multipath propagation mode when the value of the difference exceeds the threshold.
8. A reception signal processing device of a MIMO radar signal processing
5 device, the reception signal processing device comprising:
a plurality of matched filter banks, each receiving a reception signal from a
reception antenna corresponding to each of a plurality of reception antennas that capture
reflected waves obtained by transmission waves transmitted from transmission
antennas, reaching an object and being reflected as arrival waves and transmission
10 signals from the plurality of transmission signal generating units, and outputting
matched filter outputs serving as vector elements of reception signal vectors using the
transmission signals from the plurality of transmission signal generating units as a
replica of a matched filter; and
a bidirectional angle measuring unit to calculate a bidirectional measured angle
15 value constituted by a direction-of-departure and a direction-of-arrival in a reception
signal vector of interest corresponding to a range Doppler cell given in target detection
processing among reception signal vectors for matched filter outputs from the plurality
of matched filter banks.
20 9. The reception signal processing device of the MIMO radar signal processing
device according to claim 8, further comprising a propagation mode distinguishing unit
to distinguish, by the bidirectional side angle value, whether a propagation mode of a
reception signal vector of interest for the bidirectional measured angle value calculated
by the bidirectional angle measuring unit is a direct propagation mode or a multipath
25 propagation mode.
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10. A method for distinguishing a propagation mode of a reception signal vector of
interest for a reception signal obtained by converting arrival waves captured by a
plurality of reception antennas, the method comprising the step of
obtaining, by a bidirectional angle measuring unit, a bidirectional measured
5 angle value constituted by a direction-of-departure and a direction-of-arrival in a
reception signal vector of interest corresponding to a range Doppler cell given in target
detection processing among reception signal vectors for matched filter outputs output
from a plurality of matched filter banks.