FMCW radar with dynamic waveform model based on ego motion

1 . A method performed by a radar sensor system, the method comprising:

transmitting by a radar sensor a radar signal having a predefined pulse repetition interval (PRI);

monitoring ego velocity of the radar sensor;

detecting that the ego velocity has crossed one or more predetermined ego velocity thresholds; and

decreasing the predefined PRI upon detecting that the ego velocity exceeds one of the one or more predetermined ego velocity thresholds; and

increasing the predefined PRI upon detecting that the ego velocity falls below one of the one or more predetermined ego velocity thresholds;

wherein decreasing or increasing the predefined PRI comprises generating a computed PRI value as a function of the ego velocity and a predetermined maximum detectable target radial velocity such that a maximum unambiguous radial velocity for the computed PRI and a carrier frequency of the radar signal is at least equal to a sum of the ego velocity and the predetermined maximum detectable target radial velocity.

2 . The method of claim 1 , wherein:

a first predetermined ego velocity threshold is one of the one or more predetermined ego velocity thresholds; and

the first predetermined ego velocity threshold represents an ego velocity below which the predefined PRI is applied for radar signal transmission, and above which the predefined PRI is decreased.

3 . The method of claim 1 , further comprising detecting that the ego velocity has exceeded a second predetermined ego velocity threshold that is one of the one or more predetermined ego velocity thresholds that is higher than the first predetermined ego velocity threshold by at least one of a predetermined amount and a predetermined percentage, and further decreasing the predefined PRI upon detecting that the ego velocity exceeds the second predetermined ego velocity threshold.

4 . The method of claim 1 , wherein the one or more predetermined ego velocity thresholds comprise a plurality of predetermined ego velocity thresholds.

5 . The method of claim 4 , further comprising detecting a decrease in the ego velocity to a level below one of the plurality of predetermined ego velocity thresholds, and increasing the predefined PRI based on the one of the plurality of the predetermined ego velocity thresholds.

6 . The method of claim 1 , further comprising detecting a decrease in the ego velocity to a level below a first predetermined ego velocity threshold, the first predetermined ego velocity threshold being one of the one or more predetermined ego velocity thresholds and increasing the predefined PRI.

7 . The method of claim 6 , further comprising generating the computed PRI value based on at least the predetermined maximum detectable target radial velocity and the ego velocity of the radar sensor.

8 . A radar sensor system comprising:

a transmit antenna configured to transmit a radar signal into an environment of the radar sensor system;

a receive antenna configured to receive a return signal from the environment of the radar sensor system responsive to the radar signal; and

radar processing circuitry that is configured to perform acts comprising:

causing the transmit antenna to transmit a radar signal having a predefined pulse repetition interval (PRI);

monitoring ego velocity of the radar sensor;

detecting that the ego velocity has crossed one or more predetermined ego velocity thresholds;

decreasing the predefined PRI upon detecting that the ego velocity exceeds one of the one or more predetermined ego velocity thresholds; and

increasing the predefined PRI upon detecting that the ego velocity falls below one of the one or more predetermined ego velocity thresholds; and

wherein decreasing or increasing the predefined PRI comprises generating a computed PRI value as a function of the ego velocity and a predetermined maximum detectable target radial velocity such that a maximum unambiguous radial velocity for the computed PRI value and a carrier frequency of the radar signal is at least equal to a sum of the ego velocity and the predetermined maximum detectable target radial velocity.

9 . The radar sensor system of claim 8 , further comprising detecting that is one of the one or more predetermined ego velocity thresholds that represents an ego velocity below which the predefined PRI is applied for radar signal transmission, and above which the predefined PRI is decreased.

10 . The radar sensor system of claim 9 , further comprising detecting that the ego velocity has exceeded a second predetermined ego velocity threshold that is one of the one or more predetermined ego velocity thresholds that is higher than the first predetermined ego velocity threshold by at least one of a predetermined amount and a predetermined percentage, and further decreasing the predefined PRI upon detecting that the ego velocity exceeds the second predetermined ego velocity threshold.

11 . The radar sensor system of claim 10 , wherein the one or more predetermined ego velocity thresholds comprise a plurality of equally spaced predetermined ego velocity thresholds.

12 . The radar sensor system of claim 11 further comprising detecting a decrease in the ego velocity to a level below one of the plurality of predetermined ego velocity thresholds, and increasing the predefined PRI based on the one of the plurality of ego velocity thresholds.

13 . The radar sensor system of claim 9 , further comprising detecting a decrease in the ego velocity to a level below the first predetermined ego velocity threshold and increasing the predefined PRI PRI.

14 . The radar sensor system of claim 8 , further comprising generating the computed PRI value based on at least the predetermined maximum detectable target radial velocity and the ego velocity of the radar sensor.

15 . A central processing unit comprising:

a computer-readable medium having stored thereon instructions which, when executed by a processor, cause the processor to perform certain acts;

one or more processors configured to execute the instructions, the acts comprising:

causing a transmit antenna to transmit a radar signal having a predefined pulse repetition interval (PRI);

monitoring ego velocity of the radar sensor;

detecting that the ego velocity has crossed one or more predetermined ego velocity threshold; and

decreasing the predefined PRI upon detecting that the ego velocity exceeds one of the one or more predetermined ego velocity thresholds; and

increasing the predefined PRI upon detecting that the ego velocity falls below one of the one or more predetermined ego velocity thresholds; wherein decreasing or increasing the predefined PRI comprises generating a computed PRI value as a function of the ego velocity and a predetermined maximum detectable target radial velocity such that a maximum unambiguous radial velocity for the computed PRI value and a carrier frequency of the radar signal is at least equal to a sum of the ego velocity and the predetermined maximum detectable target radial velocity.

16 . The central processing unit of claim 15 , wherein a first predetermined ego velocity threshold is one of the one or more predetermine ego velocity thresholds, and wherein the first predetermined ego velocity threshold represents an ego velocity below which the predefined PRI is applied for radar signal transmission, and above which the predefined PRI is decreased.

17 . The central processing unit of claim 15 , further comprising detecting that the ego velocity has exceeded a second predetermined ego velocity threshold that is one of the one or more predetermined ego thresholds that is higher than the first predetermined ego velocity threshold by at least one of a predetermined amount and a predetermined percentage, and further decreasing the predefined PRI upon detecting that the ego velocity exceeds the second predetermined ego velocity threshold.

18 . The central processing unit of claim 17 , wherein the one or more predetermined ego velocity thresholds comprise a plurality of equally spaced predetermined ego velocity thresholds.

19 . The central processing unit of claim 18 , further comprising detecting a decrease in the ego velocity to a level below one of the plurality of predetermined ego velocity thresholds, and increasing the predefined PRI based on the one of the plurality of predetermined ego velocity thresholds.

20 . The central processing unit of claim 15 , further comprising detecting a decrease in the ego velocity to a level below a first predetermined ego velocity threshold, the first predetermined ego velocity threshold being one of the one or more predetermined ego velocity thresholds, and increasing the predefined PRI.