System and method for asynchronous transmission of communication data to a periodically blanked radar receiver

• US 7,453,391 B1
• Filed: 11/03/2006
• Issued: 11/18/2008
• 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 K
• Application Number:
  US11/592,376
• Time in Patent Office: 746 Days
• Field of Search: 342/57, 342/30
• US Class Current: 342/57
• 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 for asynchronously transmitting bursts of data from a communications terminal to a burst radar transceiver is disclosed. The burst radar can transmit a plurality of bursts, each separated by an inter-burst interval. An inter-burst interval length of the burst radar transceiver can be established. A burst of data at the communications terminal can be formed having a terminal burst interval length less than half the inter-burst interval of the burst radar transceiver. The burst of data can be transmitted a plurality of times from the communications terminal to the burst radar transceiver.

Claims

1. A method of asynchronously transmitting bursts of data from a communications terminal to a burst radar transceiver configured to transmit a plurality of bursts, each burst separated by an inter-burst interval, comprising:

establishing an inter-burst interval length of the burst radar transceiver;

forming a burst of data at the communications terminal having a terminal burst interval length less than half the inter-burst interval of the burst radar transceiver; and

transmitting the burst of data a plurality of times from the communications terminal to the burst radar transceiver to enable the burst radar transceiver to receive the burst of data, wherein the burst of data is transmitted at least P times, wherein P is an integer closest to and greater than or equal to 2N/(N−

M), N and M are positive numbers, and M/N is a duty cycle of the burst radar transceiver.

2. A method as in claim 1, wherein establishing the inter-burst interval length further comprises knowing the inter-burst interval length at the communications terminal prior to receiving information from the burst radar transceiver.

3. A method as in claim 1, wherein establishing the inter-burst interval length further comprises transmitting at least two radar bursts from the mobile radar transceiver to the communications terminal, wherein the at least two radar bursts are separated by the inter-burst interval to enable the communications terminal to determine the inter-burst interval length.

4. A method as in claim 3, wherein transmitting the at least two radar bursts further comprises transmitting at least two radar bursts, wherein the radar bursts include data modulated onto the radar bursts to form modulated radar burst signals.

5. A method as in claim 1, wherein transmitting the burst of data a plurality of times further comprises transmitting the burst of data a sufficient number of times such that a time duration of the plurality of transmitted bursts is equal to or greater than a burst radar transceiver signal period.

6. A method as in claim 1, further comprising adding a sync word to the burst of data transmitted from the communications terminal to enable a clock reference at the burst radar transceiver to be substantially synchronized with the burst of data.

7. A method as in claim 1, wherein transmitting the burst of data further comprises transmitting the burst of data having burst lengths less than 500 microseconds.

8. A method as in claim 1, wherein transmitting the burst of data further comprises transmitting the burst of data having burst lengths less than 25 microseconds.

9. A method as in claim 1, wherein transmitting the burst of data further comprises transmitting the burst of data having at least 100 symbols modulated onto the burst of data.

10. A method as in claim 1, wherein transmitting the burst of data further comprises transmitting each burst from the communications terminal to the burst radar transceiver three consecutive times with the same data to enable the burst radar transceiver to receive the burst of data without the communications terminal having knowledge of the burst radar transceiver'"'"'s inter-burst interval timing.

11. A method as in claim 1, further comprising adding an index number to each burst of data to enable the burst radar transceiver to identify duplicate bursts of data.

12. A method as in claim 1, further comprising receiving the burst of data at the burst radar transceiver.

13. A method of asynchronously transmitting bursts of data from a communications terminal to a burst radar transceiver configured to transmit a plurality of bursts each separated by an inter-burst interval, comprising:

establishing a radar burst transmit duty cycle of the burst radar transceiver, wherein the radar burst transmit duty cycle is M/N and the inter-burst interval of the burst radar transceiver is 1−

M/N, where M and N are positive numbers;

forming a burst of data at the communications terminal having a terminal burst interval length less than half the inter-burst interval length of the burst radar transceiver; and

transmitting the burst of data P times, where P is an integer closest to and greater than or equal to a quantity of 2N/(N−

M), wherein the burst of data is transmitted from the communications terminal to the burst radar transceiver to enable the burst radar transceiver to receive the burst of data during an inter-burst interval without the communications terminal having knowledge of the burst radar transceiver'"'"'s inter-burst interval timing.

14. A method as in claim 13, further comprising receiving the burst of data at the burst radar transceiver.

15. A method as in claim 14, wherein receiving the burst of data at the burst radar transceiver occurs during the inter-burst interval.

16. A method as in claim 14, wherein receiving the burst of data at the burst radar transceiver occurs during the inter-burst interval.

17. A system for asynchronously transmitting bursts of data from a communications terminal to a burst radar transceiver, comprising

an inter-burst timing device to establish a length of inter-burst intervals of the burst radar transceiver;

a communications device for forming a burst of data at the communications terminal having a terminal burst interval length less than half the inter-burst interval of the burst radar transceiver; and

a transmitter coupled to the communications terminal, the communications device, and the inter-burst timing device, wherein the transmitter is configured to transmit the burst of data a plurality of times to enable the burst of data to be received at the burst radar transceiver during the inter-burst interval, wherein the burst of data is transmitted at least P times, wherein P is an integer closest to and greater than or equal to 2N/(N−

M), N and M are positive numbers, and M/N is a duty cycle of the burst radar transceiver.

18. A system as in claim 17, wherein the inter-burst timing device is configured to receive at least two radar bursts that are separated by the inter-burst interval to enable the inter-burst timing device to determine the inter-burst interval length.

19. A means for asynchronously transmitting bursts of data from a communications terminal to a burst radar transceiver configured to transmit a plurality of bursts each separated by an inter-burst interval, comprising:

a determining means for establishing an inter-burst interval length of the burst radar transceiver;

a communications means for forming a burst of data at the communications terminal having a terminal burst interval length less than half the inter-burst interval of the burst radar transceiver; and

a transmission means for transmitting the burst of data a plurality of times from the communications terminal to the burst radar transceiver to enable the burst transceiver to receive the burst of data without knowledge of the burst radar transceiver'"'"'s inter-burst interval timing, wherein the burst of data is transmitted at least P times, wherein P is an integer closest to and greater than or equal to 2N/(N−

M), N and M are positive numbers, and M/N is a duty cycle of the burst radar transceiver.