Low Power Fast Impulse Radio Synchronization

• US 20090103671A1
• Filed: 05/15/2005
• Published: 04/23/2009
• Est. Priority Date: 05/13/2004
• Status: Active Grant

• Current Assignee: Zebra Technologies Corporation
• Original Assignee: Sandlinks Systems Ltd.
• Inventors: Kaplan, Gideon, Raphaeli, Dan
• Granted Patent: US 7,756,230 B2
• Time in Patent Office: Days
• US Class Current: 375/354
• CPC Class Codes: G06K 7/10306 ultra wide band
• CPC Class Codes: H04B 1/7183 Synchronisation
• CPC Class Codes: H04L 7/0079 Receiver details
• CPC Class Codes: H04L 7/04 Speed or phase control by synchronisation signals H04L7/0075 takes precedence

Abstract

A method for synchronizing on a pulsed waveform sequence including pulsed waveforms. An impulse radio receiver is provided including a radio frequency (RF) front end connected to a demodulator, and the demodulator is connected to a processing unit. Power is provided to at least a portion of an RF component such as the RF front end and/or the demodulator, during time windows sufficient for testing an hypothesis regarding timing of the pulsed waveforms. The powering is controlled by the processing unit. Preferably, testing the hypothesis includes accumulating a signal of the pulsed waveforms, correlating with the pulsed waveforms, or accumulating the correlation result of the pulsed waveforms. Preferably, others functions of the receiver are powered or enabled subsequent to the testing. Preferably, the impulse radio receiver is an ultra-wide band receiver.

Claims

1. A method for synchronizing on a pulsed waveform sequence including at least one pulsed waveform, the method comprising the steps of:

(a) providing an impulse radio receivers including a radio frequency (RF) front end, said RF front end operatively connected to a demodulator, said demodulator operatively connected to a processing unit; and

(b) powering at least a portion of at least one RF component selected from the group consisting of said RF front end and said demodulator, solely during at least one time window sufficient for testing at least one hypothesis regarding timing of the at least one pulsed waveform;

wherein said powering is controlled by said processing unit.

2. The method according to claim 1, further comprising the step of:

(c) testing said at least one hypothesis wherein said testing includes accumulating at least one signal of the at least one pulsed waveform.

3. The method, according to claim 1, further comprising the step of:

(c) testing said at least one hypothesis wherein said testing includes correlating with the at least one pulsed waveform.

4. The method according to claim 1, further comprising the step of:

(c) testing said at least one hypothesis wherein said testing includes;

(i) correlating with the at least one pulsed waveform, thereby obtaining a correlation result;

(ii) accumulating said correlation result of the at least one pulsed waveform.

5. The method according to claim 1, further comprising the step of:

(c) powering at least one other function of said receiver subsequent to said testing.

6. The method, according to claim 1, wherein said impulse radio receiver is an ultra-wide band receiver.

7. The method, according to claim 1, wherein the at least one pulsed waveform includes a series of pulses modulated by a binary sequence.

8. The method, according to claim 1, wherein said at least one hypothesis includes a plurality of hypotheses, and wherein said powering allows testing a plurality of hypotheses in parallel regarding timing of the pulsed waveform sequence.

9. The method according to claim 8, further comprising the steps of:

(c) scanning for and thereby acquiring the pulsed waveform sequence by said processing unit, wherein said acquiring is achieved with a non-negligible probability of a false alarm; and

wherein said plurality of hypotheses is tested in parallel, whereby performance is maintained despite the non-negligible probability of a false alarm.

10. The method according to claim 9, wherein the pulsed waveform sequence includes a plurality of pulsed waveforms, wherein a time interval between consecutive said pulsed waveforms is uniform.

11. The method according to claim 9, wherein said scanning is performed every T1 seconds, wherein T1 is not an integral multiple of a time interval between consecutive said pulsed waveforms.

12. The method according to claim 9, further comprising the step of:

(d) storing state variables pertaining to the receiver;

(e) said powering down at least a portion of at least one component of the receiver;

(f) powering up and restoring said at least one component of the receiver;

whereby upon reading said state variables, said powering up and restoring is expedited.

13. The method, according to claim 12, wherein said restoring includes restoring an oscillator frequency.

14. An impulse radio receiver for synchronization on a pulsed waveform sequence including at least one pulsed waveform, the impulse radio receiver comprising

(a) a radio frequency (RF) front end;

(b) a demodulator operatively connected to said RF front end;

(c) a processing unit operatively connected to said demodulator;

wherein said processing unit includes a switching mechanism which powers at least a portion of an RF component selected from the group consisting of said RF front end and said demodulator, solely during at least one time window sufficient for testing at least one hypothesis regarding timing of the pulsed waveform.

15. The receiver, according to claim 14, wherein said processing unit includes:

(i) a plurality of fingers which scan for and acquire the pulsed waveform sequence, wherein the outputs of said fingers are all operatively connected to said switching mechanism.

16. The receiver, according to claim 15, wherein said plurality of fingers is configured to test multiple hypotheses in parallel.

17. The receiver, according to claim 15, wherein said fingers are operatively connected to an event generator which triggers said fingers to scan for at least one pulse waveform of the pulsed waveform sequence.

18. The receiver, according to claim 15, wherein each said finger further includes at least one mechanism for performing a function selected from the group consisting of self-activation, self-deactivation, activation of another finger, deactivation of another finger, turn on other functions of the receiver.

19. An impulse radio receiver for synchronization on a plurality of sequences of pulsed waveforms emanating respectively from a plurality of communications links, the receiver comprising:

(a) a radio frequency (RF) front end

(b) a demodulator operatively connected to said RF front end;

(c) a processing unit operatively connected to said demodulator;

wherein said processing unit includes;

a switching mechanism which switches power to at least a portion of an RF component selected from the group consisting of said RF front end and said demodulator, solely during at least one time window sufficient for testing in parallel a plurality of hypotheses regarding timing of the pulsed waveform sequences, and

a plurality of fingers which scan for and acquire at least one pulsed waveform each of the pulsed waveform sequences, wherein the outputs of said fingers are all operatively connected to said switching mechanism,

wherein said plurality of fingers acquire and demodulate the pulsed waveform sequences in parallel.

20. The impulse radio receiver, according to claim 19, wherein said fingers each include a mechanism which turns on a plurality of receiver functions respective to the communications links.