Radar apparatus

Patent metadata

Field	Value
Publication number	US-2020011983-A1
Application number	US-201716489548-A
Country	US
Kind code	A1
Filing date	Mar 31, 2017
Priority date	Mar 31, 2017
Publication date	Jan 9, 2020
Grant date	—

Abstract

Transmission radars (1-nTX) (nTX=1, 2, . . . , NTX) generate mutually different modulation codes Code(nTX, h) by cyclically shifting the same code sequence by mutually different cyclic shift amounts Δτ(nTX), and generate mutually different transmission RF signals (4-nTX) using the mutually different modulation codes Code(nTX, h). As a result, the number of transmission radars 1-nTX can be made larger, and target detection accuracy can be made higher than in a case where orthogonal codes are used as mutually different modulation codes.

First claim

1 .- 9 . (canceled)

10 . A radar apparatus comprising:
a plurality of transmission radars which generate mutually different modulation codes by cyclically shifting the same code sequence by mutually different cyclic shift amounts, generate mutually different transmission signals using the mutually different modulation codes, and emit the mutually different transmission signals; a reception radar which receives reflected waves of the transmission signals reflected by a target to be observed after the transmission signals are emitted from the plurality of transmission radars, and outputting a reception signal of the reflected waves; a signal processor which performs code demodulation on the reception signal output from the reception radar, using the modulation codes generated by the plurality of transmission radars; and a target detector which detects the target on a basis of a signal subjected to the code demodulation performed by the signal processor,
wherein the signal processor includes:
a frequency domain converter which converts the reception signal output from the reception radar into a frequency domain signal; and
a code demodulator which performs code demodulation on the frequency domain signal converted by the frequency domain converter, using the modulation codes generated by the plurality of transmission radars.

11 . The radar apparatus according to claim 10 , wherein the signal processor includes an integrator which integrates the signal subjected to the code demodulation performed by the code demodulator, and outputs the integrated signal to the target detector.

12 . The radar apparatus according to claim 11 , wherein the integrator includes a first integrator which coherently integrates the signal subjected to the code demodulation performed by the code demodulator, by performing hit-direction complex integration on the signal subjected to the code demodulation.

13 . The radar apparatus according to claim 12 , wherein the integrator includes a second integrator which integrates the signal integrated by the first integrator, on a basis of positions of the plurality of transmission radars, a position of the reception radar, and an assumed value of an angle with the target.

14 . The radar apparatus according to claim 11 , wherein the integrator includes a first integrator coherently integrates the signal subjected to the code demodulation performed by the code demodulator, by performing hit-direction Fourier Transform on the signal subjected to the code demodulation.

15 . The radar apparatus according to claim 14 , wherein the integrator includes a second integrator which integrates the signal integrated by the first integrator, on a basis of positions of the plurality of transmission radars, a position of the reception radar, and an assumed value of an angle with the target.

16 . The radar apparatus according to claim 10 , wherein the plurality of transmission radars use an M-sequence as the code sequence.

17 . The radar apparatus according to claim 10 , wherein the plurality of transmission radars use, as the code sequence, a cyclic code having a cross-correlation value that varies with cyclic shift amounts, set mutually different cyclic shift amounts on a basis of a value of integral of the cross-correlation value with the cyclic code, and cyclically shift the code sequence by the set cyclic shift amounts.

Assignees

• Mitsubishi Electric Corp

Inventors

• Kageme Satoshi
• Hara Teruyuki
• Ito Masanori

Classifications

• G01S7/282

  Transmitters · CPC title

• G01S13/325 Primary

  using transmission of coded signals, e.g. P.S.K. signals · CPC title

• G01S13/286

  frequency shift keyed · CPC title

• G01S13/225

  with cyclic repetition of a non-uniform pulse sequence, e.g. staggered PRF · CPC title

• G01S13/42 Primary

  Simultaneous measurement of distance and other co-ordinates (indirect measurement G01S13/46) · CPC title