System and method for generating a radar detection threshold

• US 7,336,219 B1
• Filed: 12/30/2005
• Issued: 02/26/2008
• Est. Priority Date: 12/30/2005
• Status: Active Grant

• Current Assignee: Valeo Radar Systems, Inc. (Valeo SE)
• Original Assignee: Valeo Raytheon Systems, Inc. (Valeo SE)
• Inventors: Lohmeier, Stephen P., Wimmer, Wilson J.
• Primary Examiner(s): Tarcza; Thomas H.
• Assistant Examiner(s): Chen; Shelley
• Application Number:
  US11/322,684
• Time in Patent Office: 788 Days
• Field of Search: 342/159
• US Class Current: 342/159
• CPC Class Codes: G01S 13/34 using transmission of continuous, frequency-modulated waves while heterodyning the received signal, or a signal derived therefrom, with a locally-generated signal related to the contemporaneously transmitted signal
• CPC Class Codes: G01S 13/48 using multiple beams at emission or reception
• CPC Class Codes: G01S 13/931 of land vehicles
• CPC Class Codes: G01S 2013/9315 Monitoring blind spots
• CPC Class Codes: G01S 2013/9321 Velocity regulation, e.g. cruise control
• CPC Class Codes: G01S 2013/93274 on the side of the vehicles
• CPC Class Codes: G01S 7/2922 by using a controlled threshold
• CPC Class Codes: G01S 7/354 Extracting wanted echo-signals Doppler systems G01S13/50
• CPC Class Codes: G01S 7/356 involving particularities of FFT processing

Abstract

A method for generating a radar detection threshold includes computing a first plurality of percentile values associated with frequency domain values of frequency domain signals. The first plurality of percentile values is used to generate detection threshold values. Apparatus for generating a radar detection threshold includes a first percentile processor adapted to compute a first plurality of percentile values associated with frequency domain values of frequency domain signals. A threshold processor is adapted to use the plurality of percentile values to generate detection threshold values.

Claims

1. A method of generating a radar threshold associated with a radar, comprising:

transmitting a plurality of radio frequency (RF) signals;

receiving a plurality of composite signals, each composite signal including at least one of a received RF signal and a noise signal;

converting the plurality of composite signals to provide a plurality of baseband signals;

transforming the plurality of baseband signals to the frequency domain to provide a respective plurality of frequency domain signals, each one of the plurality of frequency domain signals having a corresponding plurality of frequency domain values and a respective plurality of frequency bins;

computing a first plurality of percentile values from the plurality of frequency domain values associated with at least two of the plurality of frequency domain signals; and

generating a detection threshold associated with the first plurality of percentile values.

2. The method of claim 1, wherein each one of the plurality of composite signals is associated with a same single receive beam.

3. The method of claim 1, wherein the transmitted RF signals comprise RF chirp signals.

4. The method of claim 1, wherein the generating comprises:

selecting a first offset value; and

combining the first offset value with the first plurality of percentile values.

5. The method of claim 1, wherein the generating comprises:

selecting the detection threshold values to be equal to the first plurality of percentile values.

6. The method of claim 1, wherein the computing the first plurality of percentile values comprises:

partitioning magnitudes of the plurality of frequency domain values into a plurality of magnitude ranges;

partitioning the plurality of frequency bins into a plurality of frequency bin ranges;

counting numbers of frequency domain values, from among the plurality of frequency domain values, that fall within the plurality of magnitude ranges at each of the frequency bin ranges; and

computing the first plurality of percentile values from the numbers of frequency domain values that fall within the plurality of magnitude ranges at each of the frequency bin ranges.

7. The method of claim 1, further comprising:

computing a second plurality of percentile values from the plurality of frequency domain values associated with the at least two of the plurality of frequency domain signals; and

combining the first plurality of percentile values and the second plurality of percentile values to provide one or more detection threshold values.

8. The method of claim 7, wherein the combining comprises selecting from among the first plurality of percentile values and the second plurality of percentile values to provide the one or more detection threshold values.

9. The method of claim 7, wherein the combining comprises selecting largest values from among the first plurality of percentile values and the second plurality of percentile values to provide the one or more detection threshold values.

10. The method of claim 7, wherein the combining comprises:

selecting a first offset value;

selecting a second offset value;

adding the first offset value to each one of the first plurality of percentile values to provide first threshold values;

subtracting the second offset value from the second plurality of percentile values to provide second threshold values; and

selecting one or more values from among the first threshold values and second threshold values to provide the one or more detection threshold values.

11. The method of claim 10, wherein at least one of the first offset value and the second offset value is equal to zero.

12. The method of claim 10, wherein the selecting one or more values from among the first threshold values and the second threshold values comprises selecting largest values from among the first threshold values and the second threshold values to provide the one or more detection threshold values.

13. The method of claim 7, wherein the computing the first plurality of percentile values comprises:

partitioning magnitudes of the plurality of frequency domain values into a plurality of magnitude ranges;

partitioning the plurality of frequency bins into a plurality of frequency bin ranges;

counting numbers of frequency domain values, from among the plurality of frequency domain values, that fall within the plurality of magnitude ranges at each of the frequency bin ranges; and

computing the first plurality of percentile values from the numbers of frequency domain values that fall within the plurality of magnitude ranges at each of the frequency bin ranges, and wherein the computing the second plurality of percentile values comprises;

partitioning magnitudes of the plurality of frequency domain values into a plurality of magnitude ranges;

partitioning the plurality of frequency bins into a plurality of frequency bin ranges;

counting numbers of frequency domain values, from among the plurality of frequency domain values, that fall within the plurality of magnitude ranges at each of the frequency bin ranges; and

computing the second plurality of percentile values from the numbers of frequency domain values that fall within the plurality of magnitude ranges at each of the frequency bin ranges.

14. The method of claim 7, wherein the radar has a field of view, the method further including moving the radar so that a variety of objects pass through the field of view.

15. The method of claim 1, wherein the radar has a field of view, the method further including moving the radar so that a variety of objects pass through the field of view.

16. Apparatus for generating a radar threshold, comprising:

a radar transmitter adapted to transmit a plurality of RF signals;

a radar receiver adapted to receive a plurality of composite signals, each composite signal including at least one of a received RF signal and a noise signal;

a baseband converter adapted to convert the plurality of composite signals to provide an associated plurality of baseband signals;

a frequency domain processor adapted to transform the plurality of baseband signals to the frequency domain to provide a respective plurality of frequency domain signals, each one of the plurality of frequency domain signals having a corresponding plurality of frequency domain values and a respective plurality of frequency bins;

a first percentile processor adapted to compute a first plurality of percentile values from the plurality of frequency domain values associated with at least two of the plurality of frequency domain signals; and

a threshold processor adapted to generate a detection threshold associated with the first plurality of percentile values.

17. The apparatus of claim 16, wherein each one of the plurality of composite signals is associated with a same single receive beam.

18. The apparatus of claim 16, wherein the transmitted RF signals comprise RF chirp signals.

19. The apparatus of claim 16, wherein the threshold processor includes:

a first threshold processor adapted to combine a first offset value to the first plurality of percentile values.

20. The apparatus of claim 16, wherein the threshold processor includes:

a selection processor adapted to select the detection threshold values to be equal to the first plurality of percentile values.

21. The apparatus of claim 16, wherein the first percentile processor comprises:

a magnitude partitioning processor adapted to partition magnitudes of the plurality of frequency domain values into a plurality of magnitude ranges;

a frequency bin partitioning processor adapted to partition the plurality of frequency bins into a plurality of frequency bin ranges; and

an occurrence processor adapted to count numbers of frequency domain values, from among the plurality of frequency domain values, that fall within the plurality of magnitude ranges at each of the frequency bin ranges, and further adapted to compute the first plurality of percentile values from the numbers of frequency domain values that fall within the plurality of magnitude ranges at each of the frequency bin ranges.

22. The apparatus of claim 16, further comprising:

a second percentile processor adapted to compute a second plurality of percentile values from the plurality of frequency domain values associated with the at least two of the plurality of frequency domain signals; and

a combining processor adapted to combine the first plurality of percentile values and the second plurality of percentile values to provide one or more detection threshold values.

23. The apparatus of claim 22, wherein the combining processor is further adapted to select one or more values from among the first plurality of percentile values and second plurality of percentile values to provide the one or more detection threshold values.

24. The apparatus of claim 22, wherein the combining processor is further adapted to select one or more values largest values from among the first plurality of percentile values and the second plurality of percentile values to provide the one or more detection threshold values.

25. The apparatus of claim 22, wherein the combining processor comprises:

a first threshold processor adapted to add a first offset value to the first plurality of percentile values to provide first threshold values;

a second threshold processor adapted to subtract a second offset value from the second plurality of percentile values to provide second threshold values; and

a selection processor adapted to select from one or more values among the first threshold values and second threshold values to provide the one or more detection threshold values.

26. The apparatus of claim 25, wherein at least one of the first offset value and the second offset value is equal to zero.

27. The apparatus of claim 25, wherein the selection processor is adapted to select one or more values largest values from among the first threshold values and the second threshold values to provide the one or more detection threshold values.

28. The apparatus of claim 22, wherein the first percentile processor comprises:

a magnitude partitioning processor adapted to partition magnitudes of the plurality of frequency domain values into a plurality of magnitude ranges;

a frequency bin partitioning processor adapted to partition the plurality of frequency bins into a plurality of frequency bin ranges; and

an occurrence processor adapted to count numbers of frequency domain values, from among the plurality of frequency domain values, that fall within the plurality of magnitude ranges at each of the frequency bin ranges, and further adapted to compute the first plurality of percentile values from the numbers of frequency domain values that fall within the plurality of magnitude ranges at each of the frequency bin ranges, and wherein the second percentile processor comprises;

a magnitude partitioning processor adapted to partition magnitudes of the plurality of frequency domain values into a plurality of magnitude ranges;

a frequency bin partitioning processor adapted to partition the plurality of frequency bins into a plurality of frequency bin ranges; and

an occurrence processor adapted to count numbers of frequency domain values, from among the plurality of frequency domain values, that fall within the plurality of magnitude ranges at each of the frequency bin ranges, and further adapted to compute the second plurality of percentile values from the numbers of frequency domain values that fall within the plurality of magnitude ranges at each of the frequency bin ranges.