Range sidelobe suppression

Patent metadata

Field	Value
Publication number	US-9739873-B2
Application number	US-201414463448-A
Country	US
Kind code	B2
Filing date	Aug 19, 2014
Priority date	Aug 19, 2014
Publication date	Aug 22, 2017
Grant date	Aug 22, 2017

Abstract

A system, apparatus, and method for receiving a signal. In one implementation, the system includes a receiver, a correlator, and a range sidelobe envelope generator. The receiver receives the signal. The correlator compresses the signal with a reference signal. The range sidelobe envelope generator generates a range sidelobe envelope function based on the compressed signal.

First claim

The invention claimed is:

1. A system for processing a signal, the system comprising:
a receiver for receiving the signal;
a correlator for compressing the signal with a reference signal, thereby resulting in a compressed signal; and
a range sidelobe envelope generator for generating, using a maximum convolution function, a range sidelobe envelope function based on the compressed signal.

2. The system of claim 1 , wherein the reference signal comprises a chirp signal.

3. The system of claim 1 , wherein the signal is compressed using auto-correlation.

4. The system of claim 1 , further comprising:
an envelope pattern table for storing a plurality of range sidelobe envelope patterns; and
wherein the range sidelobe envelope generator selects one of the range sidelobe envelope patterns, resulting in a selected range sidelobe envelope pattern.

5. The system of claim 4 , wherein the selected range sidelobe envelope pattern comprises a first plurality of samples and wherein the compressed signal comprises a second plurality of samples, and wherein the range sidelobe envelope generator further comprises:
a first multiplier for multiplying a first one of the first plurality of samples of the selected range sidelobe envelope pattern and a first one of the second plurality of samples of the compressed signal, resulting in a first product;
a second multiplier for multiplying a second one of the first plurality of samples of the selected range sidelobe envelope pattern and a second one of the second plurality of samples of the compressed signal, resulting in a second product; and
wherein the range sidelobe envelope generator selects a larger product of the first product and the second product.

6. The system of claim 1 , further comprising:
a range shifter for aligning the range sidelobe envelope function with the compressed signal.

7. The system of claim 6 , further comprising:
a clipper for clipping values of the range sidelobe envelope function that are below a predetermined value to the predetermined value.

8. An apparatus for processing a signal, the apparatus comprising:
receiver operable to receive the signal; and
a non-transitory computer-readable medium connected to the receiver, the non-transitory computer readable medium having stored thereon computer-executable instructions which, when executed by a computer, cause the computer to:
compress the signal with a reference signal, thereby resulting in a compressed signal; and
generate, using a maximum convolution function, a range sidelobe envelope function from the compressed signal.

9. The apparatus of claim 8 , wherein compressing the signal further comprises auto-correlating the signal.

10. The apparatus of claim 8 , wherein the non-transitory computer-readable medium further comprising computer-executable instructions that cause the computer to:
select a particular one of a plurality of range sidelobe envelope patterns, resulting in a selected range sidelobe envelope pattern.

11. The apparatus of claim 10 , wherein the selected range sidelobe envelope pattern comprises a first plurality of samples and wherein the compressed signal comprises a second plurality of samples, and wherein the non-transitory computer-readable medium further comprising computer-executable instructions that cause the computer to:
multiply a first one of the first plurality of samples of the selected range sidelobe envelope pattern and a first one of the second plurality of samples of the compressed signal, resulting in a first product;
multiply a second one of the first plurality of samples of the selected range sidelobe envelope pattern and a second one of the second plurality of samples of the compressed signal, resulting in a second product; and
select a larger product of the first product and the second product.

12. The apparatus of claim 8 , wherein the non-transitory computer-readable medium further comprising computer-executable instructions that cause the computer to:
align the range sidelobe envelope function with the compressed signal.

13. The apparatus of claim 12 , wherein the non-transitory computer-readable medium further comprising computer-executable instructions that cause the computer to:
clip the range sidelobe envelop function from values that are below a predetermined value to the predetermined value, thereby resulting in a clipped range sidelobe envelope.

14. A method for processing a radar signal, comprising:
receiving the radar signal with a receiver;
correlating the radar signal with a reference signal, thereby resulting in a compressed signal; and
generating, using a maximum convolution function, a range sidelobe envelope function based on the compressed radar signal.

15. The method of claim 14 , wherein the radar signal comprises a radar chirp signal.

16. The method of claim 14 , wherein compressing the radar signal comprises auto-correlating the radar signal.

17. The method of claim 14 , wherein generating the range sidelobe envelope function comprises:
selecting a particular one of a plurality range sidelobe envelope patterns, resulting in a selected range sidelobe envelope pattern.

18. The method of claim 17 , wherein the selected range sidelobe envelope pattern further comprises a first plurality of samples and wherein the compressed signal comprises a second plurality of samples, wherein the method further comprises:
multiplying a first one of the first plurality of samples of the selected range sidelobe envelope pattern and a first one of the second plurality of samples of the compressed signal, resulting in a first product;
multiplying a second one of the first plurality of samples of the range sidelobe envelope function and a second one of the second plurality of samples of the compressed signal, resulting in a second product; and
selecting a larger product of the first product and the second product.

19. The method of claim 14 , further comprising:
aligning the range sidelobe envelope function with the compressed signal.

20. The method of claim 19 , further comprising:
clipping the range sidelobe envelop function from values that are below a first predetermined value to a second predetermined value, thereby resulting in a clipped range sidelobe envelope; and
reducing the compressed signal by the amount of the clipped range sidelobe envelope.

21. A system for processing, a signal, the system comprising:
a receiver for receiving the signal;
a correlator for compressing the signal with a reference signal, thereby resulting in a compressed signal;
a range sidelobe envelope generator for generating a range sidelobe envelope function based on the compressed signal;
a range shifter for aligning the range sidelobe envelope function with the compressed signal; and
a clipper for clipping values of the range sidelobe envelope function that are below a predetermined value to the predetermined value.

22. An apparatus for processing a signal, the apparatus comprising:
receiver operable to receive the signal; and
a non-transitory computer-readable medium connected to the receiver, the non-transitory computer readable medium having stored thereon computer-executable instructions which, when executed by a computer, cause the computer to:
compress the signal with a reference signal, thereby resulting in a compressed signal;
generate a range sidelobe envelope function from the compressed signal;
align the range sidelobe envelope function with the compressed signal; and
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Assignees

• Navico Holding As

Inventors

• Lilburn Lindsay
• Phillips Roger

Classifications

• G01S7/32 Primary

  Shaping echo pulse signals; Deriving non-pulse signals from echo pulse signals · CPC title

• G01S13/284

  using coded pulses · CPC title

• G01S13/28 Primary

  with time compression of received pulses · CPC title