SYSTEM AND METHOD FOR REDUCING THE EFFECT OF A RADAR INTERFERENCE SIGNAL

• US 20070120731A1
• Filed: 12/28/2006
• Published: 05/31/2007
• Est. Priority Date: 12/15/2004
• Status: Active Grant

• Current Assignee: Valeo Radar Systems, Inc. (Valeo SE)
• Original Assignee: Valeo Radar Systems, Inc. (Valeo SE)
• Inventors: Kelly, Thomas, Woodington, Walter, Aeder, R.
• Granted Patent: US 7,683,827 B2
• Time in Patent Office: Days
• 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 7/021 Auxiliary means for detecting or identifying radar signals or the like, e.g. radar jamming signals
• CPC Class Codes: G01S 7/36 Means for anti-jamming , e.g. ECCM, i.e. electronic counter-counter measures

Abstract

A system and method are provided to reduce the effect of an interfering signal in a radar return signal for a frequency modulated continuous wave (FMCW) radar. Once the interfering signal is detected, an extent of the interfering signal is determined and the data that was corrupted by the interfering signal is not included in the processing of the radar return signal. This allows the radar to detect a target in the presence of the interfering signal. The system and method can benefit any FMCW radar that is within the range of an interfering radar source (e.g. another FMCW radar, a police radar gun, a pulse radar, etc.) operating in the same frequency band as the FMCW radar. An alternative arrangement provides a system and method for determining the frequency of the interfering signal and then avoiding transmitting power in that portion of the frequency spectrum where the interfering signal is present.

Claims

1. A method of radar processing, comprising:

receiving an RF received signal;

detecting the presence of an interfering signal within the RF received signal;

selecting a sweep range to avoid the interfering signal; and

transmitting a frequency modulated continuous wave (FMCW) RF signal having the sweep range.

2. The method of claim 1, further including:

detecting a frequency of the interfering signal, wherein the sweep range is selected to avoid the frequency of the interfering signal.

3. The method of claim 1, wherein the detecting the presence of the interfering signal comprises:

generating time samples associated with the RF received signal;

generating an array having array values associated with the time samples;

generating at least one threshold associated with the array values; and

comparing the array values with the at least one threshold.

4. The method of claim 3, further including detecting that the interfering signal exists if at least a selected number of array values reach the at least one threshold.

5. The method of claim 3, wherein the array values comprise a selected one of slope values, higher order derivative values, time sample absolute values, or power values.

6. The method of claim 3, wherein the generating at least one threshold comprises generating at least one of a first threshold related to a maximum expected array value or a second threshold related to a mean of the array values.

7. A method of radar processing, comprising:

generating time samples associated with an RF return signal;

generating an array having array values associated with the time samples;

generating at least one threshold associated with the array values; and

comparing the array values with the at least one threshold.

8. The method of claim 7, further including detecting that an interfering signal exists if at least a selected number of array values reach the at least one threshold.

9. The method of claim 7, wherein the array values comprise a selected one of slope values, higher order derivative values, time sample absolute values, or power values.

10. The method of claim 7, wherein the generating the at least one threshold comprises generating at least one of a first threshold related to a maximum expected array value or a second threshold related to a mean of the array values.

11. The method of claim 7, further including:

identifying an array sample extent from among the array values and associated with interfering signal; and

selecting a guard band value, which provides a guard band beyond the array sample extent.

12. The method of claim 11, wherein the guard band value is dynamically selected in accordance with at least one of the array sample extent or a maximum array value associated with the interfering signal.

13. A radar system, comprising:

an RF receiving module adapted to receive an RF received signal and adapted to provide a downconverted signal in response to the RF return signal;

an RF signal sampling module coupled to the RF receiving module and adapted to generate time samples associated with the downconverted signal; and

an interference detector coupled to receive the time samples, adapted to detect the presence of an interfering signal and adapted to select a sweep range to avoid the interfering signal; and

an RF transmitting module adapted to transmit a frequency modulated continuous wave (FMCW) RF signal having the sweep range.

14. The system of claim 13, wherein the interference detector includes an array processor adapted to generate an array having array values associated with the time samples, adapted to generate at least one threshold associated with the array values, and adapted to compare the array values with the at least one threshold.

15. The system of claim 14, wherein the array processor is further adapted to determine the interfering signal exists if at least the selected number of array values reach the at least one threshold.

16. The system of claim 14, wherein array values comprise a selected one of slope values, higher order derivative values, time sample absolute values, or power values.

17. The system of claim 13, wherein the at least one threshold includes at least one of a first threshold related to a maximum expected array value or a second threshold related to a mean of the array values.