Method and apparatus with radar signal processing
A radar signal processing method includes: extracting a first chirp sequence signal of a first carrier frequency and a second chirp sequence signal of a second carrier frequency from a radar signal received through an array antenna in a radar sensor; generating a first range-Doppler map by performing frequency conversion on the first chirp sequence signal; detecting a first target cell corresponding to a first target in the first range-Doppler map; determining a first ambiguous Doppler velocity of the first target based on first frequency information of the first target cell; determining a first range of an unambiguously measurable Doppler velocity through the first chirp sequence signal; estimating second ambiguous Doppler velocities based on the first ambiguous Doppler velocity and the first range; and determining a Doppler velocity of the first target by performing partial frequency conversion on the second chirp sequence signal based on the second ambiguous Doppler velocities.
1. A radar signal processing method, comprising:
determining a first ambiguous Doppler velocity of a target based on a range-Doppler map according to a first chirp sequence signal of a first carrier frequency;
estimating second ambiguous Doppler velocities according to ambiguity of the first ambiguous Doppler velocity; and
determining a Doppler velocity of the target based on an optimal ambiguity number determined by performing a partial frequency conversion on a second chirp sequence signal of a second carrier frequency based on the second ambiguous Doppler velocities.
2. The method of claim 1 , wherein the estimating the second ambiguous Doppler velocities comprises:
determining a range of an unambiguously measurable Doppler velocity through the first chirp sequence signal; and
estimating the second ambiguous Doppler velocities based on the first ambiguous Doppler velocity and the range.
3. The method of claim 2 , wherein the range is determined based on a chirp repetition period of the first chirp sequence signal.
4. The method of claim 2 , wherein the second ambiguous Doppler velocities correspond to candidates for the unambiguously measurable Doppler velocity.
5. The method of claim 1 , wherein the determining of the Doppler velocity of the target comprises:
Determining the optimal ambiguity number using the second ambiguous Doppler velocities; and
determining the Doppler velocity of the target based on the optimal ambiguity number.
6. The method of claim 1 , further comprising:
extracting the first chirp sequence signal of the first carrier frequency and the second chirp sequence signal of the second carrier frequency from a radar signal received through an array antenna in a radar sensor; and
generating the range-Doppler map by performing frequency conversion on the first chirp sequence signal.
7. The method of claim 1 , wherein determining the first ambiguous Doppler velocity of the target comprises:
detecting a target cell corresponding to a target in the first range-Doppler map; and
determining the first ambiguous Doppler velocity of the target based on frequency information of the target cell.
8. The method of claim 1 , wherein the determining of the Doppler velocity of the target comprises:
determining a range of an unambiguously measurable Doppler velocity through the first chirp sequence signal;
determining the optimal ambiguity number by performing the partial frequency conversion on the second chirp sequence signal based on the second ambiguous Doppler velocities; and
determining the Doppler velocity of the target based on the first ambiguous Doppler velocity, the optimal ambiguity number, and the range.
9. The method of claim 8 , wherein the determining of the optimal ambiguity number comprises:
mapping the second ambiguous Doppler velocities to a Doppler spectrum of the second chirp sequence signal; and
determining an ambiguity number of a value that is the greatest on the Doppler spectrum among the second ambiguous Doppler velocities to be the optimal ambiguity number.
10. The method of claim 1 , wherein the ambiguity of the first ambiguous Doppler velocity and the second ambiguous Doppler velocities is a result of an aliasing effect.
11. A non-transitory computer-readable storage medium storing instructions that, when executed by a processor, configure the processor to perform the method of claim 1 .
12. A radar signal processing apparatus, comprising:
a radar sensor configured to receive a radar signal through an array antenna; and
a processor configured to
determine a first ambiguous Doppler velocity of a target based on a range-Doppler map according to a first chirp sequence signal of a first carrier frequency extracted from the radar signal;
estimate second ambiguous Doppler velocities according to ambiguity of the first ambiguous Doppler velocity; and
determine a Doppler velocity of the target based on an optimal ambiguity number determined by performing a partial frequency conversion on a second chirp sequence signal of a second carrier frequency based on the second ambiguous Doppler velocities.
13. The apparatus of claim 12 , wherein, for the estimating the second ambiguous Doppler velocities, the processor is further configured to:
determine a range of an unambiguously measurable Doppler velocity through the first chirp sequence signal; and
estimate the second ambiguous Doppler velocities based on the first ambiguous Doppler velocity and the range.
14. The apparatus of claim 13 , wherein the range is determined based on a chirp repetition period of the first chirp sequence signal.
15. The apparatus of claim 13 , wherein the second ambiguous Doppler velocities correspond to candidates for the unambiguously measurable Doppler velocity.
16. The apparatus of claim 12 , wherein, for the determining of the Doppler velocity of the target, the processor is further configured to:
determine the optimal ambiguity number using the second ambiguous Doppler velocities; and
determine the Doppler velocity of the target based on the optimal ambiguity number.
17. The apparatus of claim 12 , wherein the processor is further configured to:
extract the first chirp sequence signal of the first carrier frequency and the second chirp sequence signal of the second carrier frequency from a radar signal received through an array antenna in a radar sensor; and
generate the range-Doppler map by performing frequency conversion on the first chirp sequence signal.
18. The apparatus of claim 12 , wherein, for the determining the first ambiguous Doppler velocity of the target, the processor is further configured to:
detect a target cell corresponding to a target in the first range-Doppler map; and
determine the first ambiguous Doppler velocity of the target based on frequency information of the target cell.
19. The apparatus of claim 12 , wherein, for the determining of the Doppler velocity of the target, the processor is further configured to:
determine a range of an unambiguously measurable Doppler velocity through the first chirp sequence signal;
determine the optimal ambiguity number by performing partial frequency conversion on the second chirp sequence signal based on the second ambiguous Doppler velocities; and
determine the Doppler velocity of the target based on the first ambiguous Doppler velocity, the optimal ambiguity number, and the range.
20. A vehicle, comprising:
a radar sensor configured to receive a radar signal through an array antenna;
a processor configured to
determine a first ambiguous Doppler velocity of a target based on a range-Doppler map according to a first chirp sequence signal of a first carrier frequency extracted from the radar signal;
estimate second ambiguous Doppler velocities according to ambiguity of the first ambiguous Doppler velocity; and
determine a Doppler velocity of the target based on an optimal ambiguity number determined by performing a partial frequency conversion on a second chirp sequence signal of a second carrier frequency based on the second ambiguous Doppler velocities; and
a controller configured to control the vehicle based on the Doppler velocity.