Flexible wideband radar receiver architecture with enhanced sensitivity, dynamic range, instantaneous bandwidth, and range window capability

• US 10,345,432 B1
• Filed: 03/29/2016
• Issued: 07/09/2019
• Est. Priority Date: 03/29/2016
• Status: Active Grant

• Current Assignee: Lockheed Martin Corporation (Martin Marietta Corporation)
• Original Assignee: Lockheed Martin Corporation (Martin Marietta Corporation)
• Inventors: Koubiadis, Fotis P., Giampaolo, Jude C.
• Primary Examiner(s): Magloire, Vladimir
• Assistant Examiner(s): Pervin, Nuzhat
• Application Number:
  US15/083,968
• Time in Patent Office: 1,197 Days
• Field of Search: 342195
• CPC Class Codes: G01S 7/352 Receivers

Abstract

A signal processing system including a plurality of receivers configured to receive a return signal from a transmitted radio frequency (RF) waveform. A mode control processor is configured to selectively and independently alter at least one characteristic of a signal down conversion process performed by each receiver. A digital signal processor is configured to integrate the outputs of the plurality of receivers.

Claims

1. A signal processing system, comprising:

a plurality of receivers configured to receive a return signal from a transmitted radio frequency (RF) waveform;

a mode control processor coupled to the plurality of receivers and configured to generate at least one control signal to selectively alter, for a single pulse repetition interval (PRI), at least one characteristic of a signal down conversion process performed by each receiver for the single PRI relative to at least one other receiver of the plurality of receivers; and

a digital signal processor configured to integrate the outputs of the plurality of receivers for the single PRI,

wherein a first subset of receivers of the plurality of receivers configures a maximum instantaneous bandwidth for the single PRI by combining, according to a same time, the received return signal individually with each of a first plurality of different waveforms having respective different frequencies.

2. The system of claim 1, wherein the at least one characteristic includes a time at which the signal down conversion process occurs.

3. The system of claim 2, wherein the at least one control signal comprises respective first control signals indicative of a time offset relative to a master clock reference to be supplied to each receiver.

4. The system of claim 3, wherein the at least one characteristic further includes a frequency of a local oscillator signal used in the signal down conversion process.

5. The system of claim 4, wherein the at least one control signal comprises respective second control signals indicative of the frequency of the local oscillator signal to be supplied to each receiver.

6. The system of claim 4, wherein the mode control processor is further configured to:

configure a first receiver of the plurality of receivers to down convert the received return signal using a first local oscillator signal of a first frequency at a first time; and

configure a second receiver of the plurality of receivers to down convert the received return signal using a second local oscillator signal of a second frequency, distinct from the first frequency, at the first time.

7. The system of claim 6, wherein the mode control processor is further configured to:

generate a first control signal, as one of said at least one control signal, indicative of the first time;

generate a second control signal, as one of said at least one control signal, indicative of the first local oscillator signal of the first frequency;

generate a third control signal, as one of said at least one control signal, indicative of the second local oscillator signal of the second frequency;

communicate the first and second control signals to the first receiver; and

communicate the first and third control signals to the second receiver.

8. The system of claim 6, wherein the mode control process is further configured to:

configure a third receiver of the plurality of receivers to down convert the received return signal using a third local oscillator signal of a third frequency at a second time; and

configure a fourth receiver of the plurality of receiver to down convert the received return signal using the third local oscillator signal of the third frequency at a third time, distinct from the second time.

9. The system of claim 8, wherein the mode control processor is further configured to:

generate a first control signal, as one of said at least one control signal, indicative of the second time;

generate a second control signal, as one of said at least one control signal, indicative of the third time;

generate a third control signal, as one of said at least one control signal, indicative of the third local oscillator signal of the third frequency;

communicate the first and third control signals to the third receiver; and

communicate the second and third control signals to the fourth receiver.

18. The system of claim 1, wherein a second subset of receivers of the plurality of receivers configures a maximum window range for the single PRI by combining, at respective different times, the received return signal individually with each of a second plurality of different waveforms having a same frequency.

10. A signal processing system, comprising:

a plurality of receivers configured to receive a return signal from a transmitted radio frequency (RF) waveform;

one or more computer processors; and

a memory in communication with the one or more computer processors and storing program instructions, the one or more computer processors operative with the program instructions to,

in response to a first control signal to set a maximum instantaneous bandwidth for a single pulse repetition interval (PRI);

configure a first receiver of the plurality of receivers to combine the received return signal with a first waveform of a first frequency at a first time for the single PRI;

configure a second receiver of the plurality of receivers to combine the received return signal with a second waveform of a second frequency different from the first frequency and at the first time for the single PRI; and

in response to a second control signal to set a maximum window range for the single PRI;

configure a third receiver of the plurality of receivers to combine the received return signal with a third waveform at a second time for the single PRI;

configure a fourth receiver of the plurality of receiver to combine the received return signal with a fourth waveform of a same frequency as that used by the third receiver and at a third time distinct from the second time of the third receiver for the single PRI.

11. The system of claim 10, wherein the one or more computer processors is further configured to, in response to the first control signal, generate a first clock control signal indicative of a time offset relative to a master clock reference.

12. The system of claim 11, wherein the one or more computer processors is further configured to, in response to the first control signal, transmit the first clock control signal to each of the first and second receivers.

13. The system of claim 11, wherein the one or more computer processors is further configured to, in response to the first control signal, generate a first local oscillator control signal indicative of the first waveform of the first frequency and a second local oscillator control signal indicative of the second waveform of the second frequency.

14. The system of claim 13, wherein the one or more computer processors is further configured to, in response to the first control signal:

transmit the first local oscillator control signal to the first receiver, and

transmit the second local oscillator control signal to the second receiver.

15. A method of processing received signals in a radar system, comprising:

receiving a return signal via at least one antenna element;

processing the received return signal using a first subset of a plurality of receivers for a single pulse repetition interval (PRI), wherein each receiver of the first subset combines the return signal at a first time with a first local oscillator signal whose frequency is distinct from local oscillator signals utilized by the remainder of the receivers of the first subset; and

processing the received return signal using a second subset of the plurality of receivers for the single PRI, wherein each receiver of the second subset combines the return signal with a second local oscillator signal of a same frequency and at a second time distinct from a time or times of combining the return signal for the remainder of the receivers of the second subset.

16. The method of claim 15, wherein said processing the received return signal with the first subset of the plurality receivers is initiated upon receipt of a first control signal.

17. The method of claim 15, wherein said processing the received return signal with the second subset of the plurality receivers is initiated upon receipt of a second control signal.