System and method for reducing rake finger processing

• US 7,447,481 B2
• Filed: 09/28/2007
• Issued: 11/04/2008
• Est. Priority Date: 07/29/2004
• Status: Expired due to Fees

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Krishnan, Ranganathan
• Primary Examiner(s): Tran; Pablo N
• Application Number:
  US11/864,689
• Publication Number:
  US 20080020713A1
• Time in Patent Office: 403 Days
• Field of Search: 455/70, 455/522, 455504-513, 455/528, 455 6711- 6713, 455/67.16, 455130-137, 455/143, 4551611-1613, 455/225, 4552261-2263, 455/13.4, 370/318, 370/331, 370/338, 370/342, 370/332, 370/317, 370/335, 375/347, 375/E1.032, 375/130, 375/136, 375/147, 375/150
• 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.