Satellite signal adaptive time-division multiplexing receiving device

• US 7,916,075 B2
• Filed: 07/09/2007
• Issued: 03/29/2011
• Est. Priority Date: 04/19/2006
• Status: Active Grant

• Current Assignee: MediaTek, Inc.
• Original Assignee: MediaTek, Inc.
• Inventors: Chen, Chun-nan
• Primary Examiner(s): Issing; Gregory C
• Application Number:
  US11/775,114
• Publication Number:
  US 20080013518A1
• Time in Patent Office: 1,359 Days
• Field of Search: 342/357.63, 342/357.77
• US Class Current: 342/357.63
• CPC Class Codes: G01S 19/24 Acquisition or tracking or demodulation of signals transmitted by the system synchronisation aspects of direct sequence spread spectrum modulation H04B1/7073
• CPC Class Codes: G01S 19/29 carrier including Doppler, related G01S19/246 takes precedence
• CPC Class Codes: G01S 19/30 code related G01S19/246 takes precedence
• CPC Class Codes: G01S 19/34 Power consumption
• CPC Class Codes: G01S 19/37 Hardware or software details of the signal processing chain
• CPC Class Codes: H04B 1/7075 with code phase acquisition
• CPC Class Codes: H04B 2001/70706 using a code tracking loop, e.g. a delay locked loop
• CPC Class Codes: H04B 2201/70707 Efficiency-related aspects

Abstract

A satellite signal adaptive time-division multiplexing receiving device is disclosed. The receiving device operates in time-division multiplexing distributed for various domains such as satellite number, Doppler frequency, code phase and accuracy. When some specific time slots of the time-division multiplexing distribution are unnecessary to be searched, the receiving device uses a disable signal to deactivate specific components such as correlator and memory thereof during those time slots to reduce power consumption.

Claims

1. A satellite signal adaptive time-division multiplexing receiving device comprising:

a correlator correlating an input signal with a PN code signal in time-division multiplexing time slots to try hypotheses of domains of code phase, Doppler frequency, satellite number and accuracy;

a memory for storing a correlation result of the correlator; and

a receiver controller outputting a disable signal to deactivate the correlator during at least one of the time-division multiplexing time slots when a specific prerequisite of the code phase, Doppler frequency, satellite number or accuracy is satisfied.

2. The device of claim 1, wherein multiplexing of the time-division multiplexing time slots for trying the hypotheses in the respective domains is adjustable.

3. The device of claim 1, further comprising a clock controller providing a clock signal with a clock rate, wherein the correlator executes correlation at a speed determined by the clock rate.

4. The device of claim 3, wherein the clock controller changes the clock rate when an operation mode of the receiving device is changed, wherein the operation mode is selected from a satellite acquiring mode and a satellite tracking mode.

5. The device of claim 3, wherein the receiver controller transmits the disable signal to the clock controller to deactivate a clock for the correlator during said at least one of the time-division multiplexing time slots.

6. The device of claim 1, wherein the receiver controller transmits the disable signal to the memory to turn a chip-enable signal of the memory off during said at least one of the time-division multiplexing time slots.

7. The device of claim 1, wherein the disable signal is generated by the receiver controller according to satellite number to be tried.

8. The device of claim 1, wherein the disable signal is generated by the receiver controller according to Doppler frequencies to be tried.

9. The device of claim 1, wherein the disable signal is generated by the receiver controller according to code phases to be tried.

10. The device of claim 1, wherein the disable signal is generated by the receiver controller according to accuracy determined by chip code spacing.

11. The device of claim 1, wherein the receiver controller has a disable signal generator for generating the disable signal, the disable signal generator comprises a plurality of counters, each of which is in charge of one domain so that a signal is generated for the corresponding domain, and a combiner for combining the signals for respective domains to output a resultant disable signal.

12. The device of claim 1, wherein multiplexing of the time-division multiplexing time slots for trying the hypotheses in the respective domains is determined by the receiver controller depending on code phase range to be searched.

13. The device of claim 1, wherein multiplexing of the time-division multiplexing time slots for trying the hypotheses in the respective domains is determined by the receiver controller depending on Doppler frequency range to be searched.

14. The device of claim 1, wherein multiplexing of the time-division multiplexing time slots for trying the hypotheses in the respective domains is determined by the receiver controller depending on satellite number to be searched.

15. The device of claim 1, wherein multiplexing of the time-division multiplexing time slots for trying the hypotheses in the respective domains is determined by the receiver controller depending on tracking accuracy.