Method and System for Utilizing Transmit Local Oscillator for Improved Cell Search and Multi-Link Communication in Multi-Mode Device

• US 20090168914A1
• Filed: 12/31/2007
• Published: 07/02/2009
• Est. Priority Date: 12/31/2007
• Status: Active Grant

• Current Assignee: Google Technology Holdings LLC (Alphabet Inc.)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Music, Wayne D., Klomsdorf, Armin W., Chance, Gregory W., Boixadera, Francesc, Harrold, William B., Muck, Markus, Bateman, David
• Granted Patent: US 8,055,211 B2
• Time in Patent Office: Days
• US Class Current: 375/267
• CPC Class Codes: H04B 1/403 using the same oscillator for generating both the transmitter frequency and the receiver local oscillator frequency
• CPC Class Codes: H04B 1/44 Transmit/receive switching
• CPC Class Codes: H04B 7/0871 using different reception schemes, at least one of them being a diversity reception scheme
• CPC Class Codes: H04B 7/0874 using subgroups of receive antennas

Abstract

A multi-receiver wireless communication device includes a transmitter, a transmit oscillator communicatively coupled to the transmitter, a receive oscillator communicatively coupled to a first receiver and second receiver, and a switching assembly having a first state in which the receive oscillator is coupled to the first and second receivers and a second state in which the receive oscillator is de-coupled from the second receiver and the transmit oscillator is coupled to the second receiver. The first receiver and the second receiver of the wireless communication device are able to operate independent of one another when the switching assembly is in the second state.

Claims

1. A multi-receiver wireless communication device comprising:

a transmitter;

a transmit oscillator communicatively coupled to the transmitter;

a first receiver;

a second receiver;

a receive oscillator communicatively coupled to the first receiver; and

a switching assembly having;

a first state in which the receive oscillator is coupled to the first and second receivers; and

a second state in which the receive oscillator is de-coupled from the second receiver and the transmit oscillator is coupled to the second receiver.

2. The wireless communication device according to claim 1, further comprising;

a processor operable to operate the first receiver and the second receiver of the wireless communication device independent of one another when the switching assembly is in the second state.

3. The wireless communication device according to claim 1, further comprising:

a processor operable to;

identify a communication mode of the wireless communication device; and

place the switching assembly in the second state in response to identifying a communication mode that at least temporarily does not utilize the transmitter.

4. The wireless communication device according to claim 3, wherein the communication mode that at least temporarily does not utilize the transmitter is at least one of:

an initial cell search;

an idle mode;

a neighbor cell monitoring gap in a traffic mode;

a Multimedia Broadcast Multicast Service monitoring of neighbor cell mode;

a Multimedia Broadcast Multicast Service monitoring of unicast cell mode; and

traffic reception.

5. The wireless communication device according to claim 3, wherein the processor is further operable to:

determine at least one of an acceptable coverage condition and a poor coverage condition; and

place the switching assembly in the second state in response to determining an acceptable coverage condition.

6. The wireless communication device according to claim 5, wherein the processor is further operable to:

place the switching assembly in the first state in response to determining a poor coverage condition.

7. The wireless communication device according to claim 5, wherein the processor is further operable to:

operate the first receiver and collect first coverage statistics;

operate the first receiver and the second receiver and collect second coverage statistics;

determine the existence of the poor coverage condition if the second coverage statistics exceed the first coverage statistics; and

determine the existence of the acceptable coverage condition if the second coverage statistics are less than the first coverage statistics.

8. The wireless communication device according to claim 1, further comprising:

a processor operable to;

sample a rate of received data;

compare the rate of received data to a threshold value; and

place the switching assembly in the second state in response to the rate of received data being less than the threshold value.

9. The wireless communication device according to claim 8, wherein:

the rate of received data is an instantaneous data rate averaged over a fixed time period.

10. The wireless communication device according to claim 8, wherein the processor is further operable to:

add at least one new interface to an SCTP bundle in response to the rate of received data being less than the threshold value.

11. The wireless communication device according to claim 1, wherein the switching assembly comprises:

a first switch having;

a first position coupling the receiver oscillator to the second receiver; and

a second position de-coupling the receive oscillator from the second receiver; and

a second switch having;

a first position coupling the transmit oscillator to the second receiver; and

a second position de-coupling the transmit oscillator from the second receiver.

12. The wireless communication device according to claim 11, wherein the first position of the first switch and the second position of the second switch substantially coincide.

13. A method for switching receiver operations in a multi-receiver wireless communication device, the method comprising:

determining a transmitter state of a wireless communication device having;

a transmitter;

a transmit oscillator communicatively coupled to the transmitter;

a first receiver;

a second receiver; and

a receive oscillator communicatively coupled to the first receiver and the second receiver; and

decoupling the receive oscillator from the second receiver and coupling the transmit oscillator to the second receiver in response to determining that the transmitter state at least temporarily does not utilize the transmitter.

14. The method according to claim 13, further comprising:

operating the first receiver and the second receiver of the wireless communication device independent of one another in response to determining that the transmitter stale at least temporarily does not utilize the transmitter.

15. The method according to claim 13, wherein the communication mode that at least temporarily does not utilize the transmitter is at least one of:

an initial cell search;

an idle mode;

a neighbor cell monitoring gap in a traffic mode;

a Multimedia Broadcast Multicast Service monitoring of neighbor cell mode;

a Multimedia Broadcast Multicast Service monitoring of unicast cell mode; and

traffic reception.

16. The method according to claim 13, further comprising:

determining one of an acceptable coverage condition and a poor coverage condition; and

performing the coupling step and the decoupling step only in response to determining an acceptable coverage condition.

17. The method according to claim 16, further comprising:

collecting first coverage statistics with the first receiver;

collecting second coverage statistics with the first receiver and the second receiver; and

determining the existence of the acceptable coverage condition if the second coverage statistics are less than the first coverage statistics.

18. A method for controlling diversity receivers in a wireless communication device, the method comprising:

defining a first data rate threshold value;

determining a rate of data being received by a wireless communication device; and

switching the first receiver and second receiver from a diversity mode to an independent-receiver operating mode in response to the rate of received data being less than the first data rate threshold value.

19. The method according to claim 18, further comprising:

defining a second data rate threshold value, the second data rate threshold value being greater than the first data rate threshold value;

switching the first receiver and second receiver from the independent-receiver operating mode to the diversity mode in response to the rate of data being greater than a second data rate threshold value.

20. The wireless communication device according to claim 18, further comprising:

adding at least one new interface to an SCTP bundle in response to the rate of received data being less than the first threshold value.