System and method for communicating low data rate information with a radar system

• US 7,612,711 B1
• Filed: 05/06/2009
• Issued: 11/03/2009
• Est. Priority Date: 11/03/2005
• Status: Active Grant

• Current Assignee: L3 Technologies, Inc. (L3Harris Technologies, Inc.)
• Original Assignee: L-3 Communications Corporation (L3Harris Technologies, Inc.)
• Inventors: Thomson, Larry S., McIntire, William K., Boesch, James J., Robbins, David H.
• Primary Examiner(s): Tarcza; Thomas H
• Assistant Examiner(s): Liu; Harry
• Application Number:
  US12/436,311
• Time in Patent Office: 181 Days
• Field of Search: 342/195, 342/357.12, 455/553.1
• US Class Current: 342/195
• CPC Class Codes: G01S 13/90 using synthetic aperture techniques , e.g. synthetic aperture radar [SAR] techniques
• CPC Class Codes: G01S 7/006 using shared front-end circuitry, e.g. antennas G01S13/765, G01S13/825 take precedence

Abstract

A method is disclosed for transmitting low data rate symbols from a communications terminal to a burst radar transceiver. A plurality of bursts can be emitted from a burst radar transceiver, each burst having a burst interval and separated by an inter-burst interval. A symbol can be transmitted from the communications terminal to the burst radar transceiver. The symbol has a symbol period that is substantially longer than a radar transceiver burst period comprising the burst interval and the inter-burst interval. Symbol energy can be accumulated during inter-burst intervals at the burst radar transceiver over a plurality of burst periods for approximately the symbol period.

Claims

1. A method for receiving low data rate symbols, the symbols having information encoded therein, the symbols being received at a burst radar transceiver having a burst period including a burst interval and an inter-burst interval, comprising:

accepting the symbol sections at the burst radar transceiver;

blanking a radar receiver during the burst interval to reduce interference between a radar transmitter and a radar receiver in the burst radar transceiver;

accumulating symbol energy at the burst radar transceiver during inter-burst intervals over a plurality of burst periods for approximately a symbol period of the low data rate symbols; and

identifying the information in the symbol based on a characteristic of the accumulated symbol energy.

2. A system for transmitting low data rate symbols to a burst radar transceiver having a burst period including a burst interval and an inter-burst interval, comprising:

a communications terminal configured to transmit a plurality of symbols to the burst radar transceiver, wherein each symbol has a symbol transmission period that is substantially longer than the radar transceiver burst period;

a blanking device coupled to the burst radar transceiver configured to substantially attenuate a received signal during the burst radar transceiver burst interval; and

an integrating device configured to accumulate symbol energy at the burst radar transceiver over a plurality of burst periods during inter-burst intervals.

3. A system as in claim 2, wherein the communications terminal includes a transmitter and a receiver.

4. A system as in claim 2, wherein the burst radar transceiver includes a transmitter and a receiver.

5. A system as in claim 4, wherein the blanking device is configured to attenuate a signal to the receiver using at least one of a physical switch and an electronic switch.

6. A system as in claim 4, wherein the blanking device is configured to substantially eliminate digital data received during a burst interval.

7. A system as in claim 4, wherein the receiver is configured to identify information in the symbol based on a characteristic of the accumulated symbol energy.

8. A system as in claim 4, further comprising a phase memory configured to enable the receiver to ensure, at an end of a first burst period of the received signal, a correct phase at a beginning of a second burst period separated from the first burst period by the inter-burst interval.

9. A system as in claim 2, wherein the symbol period is greater than one burst period.

10. A system as in claim 2, wherein the symbol period is greater than ten burst periods.

11. A system as in claim 2, wherein the plurality of symbols are encoded using forward error correction coding.