DIGITAL RADAR SYSTEMS AND METHODS

• US 20100090885A1
• Filed: 09/08/2009
• Published: 04/15/2010
• Est. Priority Date: 10/15/2008
• Status: Abandoned Application

• Current Assignee: United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration
• Original Assignee: NASA HQ's
• Inventors: MALLIK, UDAYAN
• Application Number:
  US12/555,611
• Publication Number:
  US 20100090885A1
• Time in Patent Office: Days
• US Class Current: 342/195
• CPC Class Codes: G01S 7/003 Transmission of data between radar, sonar or lidar systems and remote stations
• CPC Class Codes: G01S 7/352 Receivers

Abstract

A digital radar system includes a transmitter, the transmitter configured to transmit a signal; a receiver, the receiver configured to receive a return signal; and two analog to digital conversion (ADC) units, the ADC units configured to digitize the return signal at a rate higher than a Nyquist rate for the transmitted signal. A method of operating a digital radar includes transmitting a signal via a transmitter; receiving a return signal via a receiver; and digitizing the return signal by two analog to digital conversion (ADC) units at a rate higher than a Nyquist rate for the transmitted signal.

Claims

1. A digital radar system, comprising:

a transmitter, the transmitter configured to transmit a signal;

a receiver, the receiver configured to receive a return signal; and

two analog to digital conversion (ADC) units, the ADC units configured to digitize the return signal at a rate higher than a Nyquist rate for the transmitted signal.

2. The digital radar system of claim 1, wherein the transmitted signal has a frequency of about 1 GHz, and the ADC units digitize the return signal at a rate of about 3 GHz.

3. The digital radar system of claim 1, further comprising a system memory configured to store the digitized signal.

4. The digital radar system of claim 3, further comprising a personal computer (PC) configured to perform signal processing and display of the digitized signal, the PC being connected to the system memory via a universal serial bus (USB) link.

5. The digital radar system of claim 4, further comprising an uplink buffer connected between the system memory and the PC.

6. The digital radar system of claim 5, wherein the digitized signal is transferred between the system memory and the PC via the uplink buffer, the transfer being performed asynchronously to transmission and receiving of the signal, and wherein transmission, receiving, digitizing, storing, and transferring of the signal are performed continuously until a halt command is received from the PC.

7. The digital radar system of claim 4, wherein transmission, receiving, digitizing and storing of the signal are performed continuously for a duration of a burst cycle, and data is transferred from the system memory to the PC at the end of the burst cycle.

8. The digital radar system of claim 7, wherein the burst cycle ends when the system memory is full.

9. The digital radar system of claim 1, wherein the receiver comprises two orthogonally oriented antennae, each of the two antennae being connected to a respective one of the two ADC units via a respective switch and a respective low-noise amplifier.

10. The digital radar system of claim 9, wherein the switches are configured to be open during signal transmission, and closed during receiving of the return signal.

11. The digital radar system of claim 1, wherein the digital radar system operates at a pulse repetition rate (PRR) of up to 10 MHz with 8 received radio frequency (RF) samples per pulse repetition interval (PRI).

12. The digital radar system of claim 1, wherein the digital radar system operates at a PRR of up to 19 KHz with 4K received RF samples per PRI.

13. A method of operating a digital radar, the method comprising:

transmitting a signal via a transmitter;

receiving a return signal via a receiver; and

digitizing the return signal by two analog to digital conversion (ADC) units at a rate higher than a Nyquist rate for the transmitted signal.

14. The method of claim 13, wherein the transmitted signal has a frequency of about 1 GHz, and the return signal is digitized at a rate of about 3 GHz.

15. The method of claim 13, further comprising storing the digitized signal in a system memory.

16. The method of claim 15, further comprising performing signal processing and display of the digitized signal on a personal computer (PC), the PC being connected to the system memory via a universal serial bus (USB) link.

17. The method of claim 16, further comprising transferring the digitized signal from the system memory to the PC via an uplink buffer asynchronously to transmission and receiving of the signal.

18. The method of claim 17, further comprising performing transmission, receiving, digitizing, and transferring of the signal continuously until a halt command is received from the PC.

19. The method of claim 16, further comprising performing transmission, receiving, and digitizing of the signal continuously for a duration of a burst cycle, and transferring the digitized signal directly from the system memory to the PC at the end of the burst cycle.

20. The digital radar system of claim 19, wherein the burst cycle ends when the system memory is full.