Orthogonal linear frequency modulation for MIMO radar

Patent metadata

Field	Value
Publication number	US-9933520-B1
Application number	US-201514753887-A
Country	US
Kind code	B1
Filing date	Jun 29, 2015
Priority date	Jun 29, 2015
Publication date	Apr 3, 2018
Grant date	Apr 3, 2018

Abstract

Disclosed herein are embodiments that relate to phase coded linear frequency modulation for a radar system. Embodiments include transmitting at least one signal pulse with a binary phase shift keying (BPSK) encoding. The method also includes receiving a signal associated with reflection of the at least one transmitted signal pulse. The received signal may include at least two channels. Further, the method may also include processing the received signal to determine target information. The processing may include performing a despread operation that provides a phase offset based on a filtering range. Additionally, the processing may include performing a reconstruction operation that comprises creating a virtual spatial channel based on combining the two received channels. Yet further, the processing may include determining the target information based on the virtual spatial channel. An autonomous vehicle may be controlled based on the determined target information.

First claim

What is claimed is:

1. A method of signaling with a radar system comprising:
transmitting, by a radar unit, at least one signal pulse, wherein the transmitting comprises transmitting the at least one signal pulse with a binary phase shift keying (BPSK) encoding;
receiving, by the radar unit, a signal associated with reflection of the at least one transmitted signal pulse, wherein the received signal comprises at least two channels;
processing the received signal to determine target information, wherein the processing comprises:
performing a despread operation, wherein the despread operation provides a phase offset based on a filtering range;
performing a reconstruction operation, wherein the reconstruction operation comprises creating a virtual spatial channel based on combining the at least two channels; and
determining the target information based on the virtual spatial channel; and

controlling an autonomous vehicle based on the determined target information.

2. The method according to claim 1 , wherein the despread operation further comprises mixing each reflection signal with a respective conjugate signal.

3. The method according to claim 1 , wherein the processing further comprises, mixing, using a stretch processor, the received reflection signal with reference signals corresponding to the transmitted pulse.

4. The method according to claim 1 , wherein the BPSK encoding creates a square wave having a frequency, wherein the square wave frequency is half of a frequency of an analog-to-digital converter frequency.

5. The method according to claim 1 , wherein transmitting the at least one signal pulse comprises transmitting a waveform configured to contain clutter within half a pulse repetition frequency when processed by a receiving system.

6. The method according to claim 1 , wherein transmitting the at least one signal pulse comprises transmitting a waveform configured to place BPSK switching boundaries between range filters.

7. The method according to claim 1 , further comprising wherein transmitting the at least one signal pulse comprises transmitting a waveform having a linear frequency modulation.

8. A radar system comprising:
a radar unit comprising:
a transmitter configured to transmit at least one signal pulse with a binary phase shift keying (BPSK) encoding;
a receiver configured to receive a signal associated with reflection of the at least one transmitted signal pulse, wherein the received signal comprises at least two channels;

a processing unit being configured to:
perform a despread operation on the received signal, wherein the despread operation provides a phase offset based on a filtering range;
perform a reconstruction operation, wherein the reconstruction operation comprises creating a virtual spatial channel based on combining the at least two channels;
determine target information based on the virtual spatial channel; and
control an autonomous vehicle based on the determined target information.

9. The system according to claim 8 , wherein the despread operation further comprises mixing each reflection signal with a respective conjugate signal.

10. The system according to claim 8 , wherein the processing further comprises, mixing, using a stretch processor, the received reflection signal with reference signals corresponding to the transmitted pulse.

11. The system according to claim 8 , wherein the BPSK encoding creates a square wave having a frequency, wherein the square wave frequency is half of a frequency of an analog-to-digital converter frequency.

12. The system according to claim 8 , wherein the at least one signal pulse is configured to contain clutter within half the pulse repetition frequency when processed by a receiving system.

13. The system according to claim 8 , wherein the at least one signal pulse is configured to place BPSK switching boundaries between range filters.

14. The system according to claim 8 , further comprising wherein the at least one signal pulse has a linear frequency modulation.

15. An article of manufacture including a non-transitory computer-readable medium, having stored thereon program instructions that, if executed by a computing device, cause the computing device to perform operations comprising:
transmitting, by a radar unit, at least one signal pulse, wherein the transmitting comprises transmitting the at least one signal pulse with a binary phase shift keying (BPSK) encoding;
receiving, by the radar unit, a signal associated with reflection of the at least one transmitted signal pulse, wherein the received signal comprises at least two channels;
processing the received signal to determine target information, wherein the processing comprises:
performing a despread operation, wherein the despread operation provides a phase offset based on a filtering range;
performing a reconstruction operation, wherein the reconstruction operation comprises creating a virtual spatial channel based on combining the at least two channels; and
determining the target information based on the virtual spatial channel; and

controlling an autonomous vehicle based on the determined target information.

16. The article of manufacture according to claim 15 , wherein the despread operation further comprises mixing each reflection signal with a respective conjugate signal.

17. The article of manufacture according to claim 15 , wherein the processing further comprises mixing, using a stretch processor, the received reflection signal with reference signals corresponding to the transmitted pulse.

18. The article of manufacture according to claim 15 , wherein the BPSK encoding creates a square wave having a frequency, wherein the square wave frequency is half of a frequency of an analog-to-digital converter frequency.

19. The article of manufacture according to claim 15 , wherein transmitting the at least one signal pulse comprises transmitting a waveform configured to contain clutter within half the pulse repetition frequency when processed by a receiving system.

20. The article of manufacture according to claim 15 , wherein transmitting the at least one signal pulse comprises transmitting a waveform configured to place BPSK switching boundaries between range filters.

21. The article of manufacture according to claim 15 , further comprising wherein transmitting the at least one signal pulse comprises transmitting a waveform having a linear frequency modulation.

Assignees

• Waymo Llc

Inventors

• Campbell Timothy

Classifications

• G01S13/325

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

• G01S13/343

  using sawtooth modulation · CPC title

• G01S2013/9319

  Controlling the accelerator · CPC title

• G01S13/42

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

• G01S13/931 Primary

  of land vehicles · CPC title