SYSTEM AND METHOD FOR REDUCING RAKE FINGER PROCESSING

• US 20080020713A1
• Filed: 09/28/2007
• Published: 01/24/2008
• Est. Priority Date: 07/29/2004
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Krishnan, Ranganathan
• Granted Patent: US 7,447,481 B2
• Time in Patent Office: Days
• US Class Current: 455/70
• CPC Class Codes: H04B 1/7115 Constructive combining of multi-path signals, i.e. RAKE receivers
• CPC Class Codes: H04B 1/7117 Selection, re-selection, allocation or re-allocation of paths to fingers, e.g. timing offset control of allocated fingers
• CPC Class Codes: H04W 52/24 using SIR [Signal to Interference Ratio] or other wireless path parameters
• CPC Class Codes: H04W 52/362 Aspects of the step size

Abstract

Systems and techniques are disclosed relating to reducing the number of fingers in a rake receiver used for rake finger processing in wireless networks. Determining E_before, captured energy of all fingers before increasing transmit power. Increasing transmit power by a delta transmit power. Determining E_after, captured energy of i fingers. Determining i fingers needed for processing, such that E_after is essentially greater than or equal to E_before.

Claims

1. A method for controlling rake finger processing in a receiver, the method comprising:

determining E_before, captured energy of all fingers before an increase in transmit power;

determining E_after, captured energy of i fingers after the increase in transmit power; and

determining i fingers needed for processing, such that E_after is essentially greater than or equal to E_before.

2. The method of claim 1, wherein the increase in transmit power is 3 dB.

3. The method of claim 1, wherein the increase in transmit power is based on a desired reduction in receive power consumption.

4. The method of claim 1, wherein the increase in transmit power is based on a signal-to-interference-and-noise ratio (SINR).

5. The method of claim 1, wherein the increase in transmit power is based on a multipath power profile.

6. The method of claim 1, further comprising transmitting a request to perform the increase in transmit power.

7. A wireless terminal, comprising:

a transceiver coupled to an antenna;

a demodulator including a searcher and a plurality of fingers;

a microprocessor coupled to the demodulator;

the microprocessor configured to;

determine E_before, captured energy of all of the plurality of fingers before an increase in transmit power;

determine E_after, captured energy of i fingers after the increase in transmit power; and

determine i fingers of the plurality of fingers needed for processing, such that E_after is essentially greater than or equal to E_before.

8. The wireless terminal of claim 7, wherein the increase in transmit power is 3 dB.

9. The wireless terminal of claim 7, wherein the increase in transmit power is based on a desired reduction in receive power consumption.

10. The wireless terminal of claim 7, wherein the increase in transmit power is based on a signal-to-interference-and-noise ratio (SINR).

11. The wireless terminal of claim 7, wherein the increase in transmit power is based on a multipath power profile.

12. The wireless terminal of claim 7, wherein the microprocessor is further configured to transmit a request to perform the increase in transmit power.

13. Computer readable media embodying a program of instructions executable by a computer program, said computer readable media comprising:

a computer readable program code means for determining E_before, captured energy of all fingers before an increase in transmit power;

a computer readable program code means for determining E_after, captured energy of i fingers after the increase in transmit power; and

a computer readable program code means for determining i fingers needed for processing, such that E_after is essentially greater than or equal to E_before.

14. A wireless terminal, comprising:

means for determining E_before, captured energy of all fingers before an increase in transmit power;

means for determining E_after, captured energy of i fingers after the increase in transmit power; and

means for determining i fingers needed for processing, such that E_after is essentially greater than or equal to E_before.