SELF-TEST USING INTERNAL FEEDBACK FOR TRANSMIT SIGNAL QUALITY ESTIMATION

• US 20150092825A1
• Filed: 06/12/2014
• Published: 04/02/2015
• Est. Priority Date: 09/27/2013
• Status: Abandoned Application

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: GAO, Li, ZHANG, Dongbo, AGRAWAL, Abhishek Kumar, GROVER, Douglas, LEE, Chalin Chac, FADLULLAH, Jarir Muhammad, VAIDYANATHAN, Rema
• Application Number:
  US14/303,594
• Publication Number:
  US 20150092825A1
• Time in Patent Office: Days
• US Class Current: 375/224
• CPC Class Codes: H04L 1/20 using signal quality detector
• CPC Class Codes: H04L 1/243 at the transmitter, using a loop-back

Abstract

A method, an apparatus, and a computer program product for wireless communication are provided. The apparatus correlates the feedback signal to a reference transmit signal to correct time misalignments between the transmit chain and the feedback loop, wherein the reference transmit signal is generated in digital domain at an input to a transmit chain and estimates a transmit signal quality value based on the correlation.

Claims

1. A method for self-testing a user equipment to determine transmit signal quality based on a feedback signal sample retrieved at output of a transmit chain, comprising:

correlating the feedback signal to a reference transmit signal to correct time misalignments between the transmit chain and the feedback loop, wherein the reference transmit signal is generated in digital domain at an input to a transmit chain; and

estimating a transmit signal quality value based on the correlation.

2. The method of claim 1, wherein the correlating further comprises determining a feedback receiver response compensation based on feedback signal response to the reference transmit signal.

3. The method of claim 2, wherein the correlating further comprises calculating a relative time delay between the feedback receiver and a transmitter of the transmit chain.

4. The method of claim 1, wherein the transmit signal quality value comprises an error vector magnitude (EVM).

5. The method of claim 1, wherein the transmit signal quality value comprises an adjacent channel leakage ratio.

7. The apparatus of claim 1, wherein the means for correlating determines a feedback receiver response compensation based on feedback signal response to the reference transmit signal.

8. The apparatus of claim 2, wherein the means for correlating calculates a relative time delay between the feedback receiver and a transmitter of the transmit chain.

9. The apparatus of claim 1, wherein the transmit signal quality value comprises an error vector magnitude (EVM).

10. The apparatus of claim 1, wherein the transmit signal quality value comprises an adjacent channel leakage ratio.

6. An apparatus for self-testing a user equipment to determine transmit signal quality based on a feedback signal sample retrieved at output of a transmit chain, comprising:

means for correlating the feedback signal to a reference transmit signal to correct time misalignments between the transmit chain and the feedback loop, wherein the reference transmit signal is generated in digital domain at an input to a transmit chain; and

means for estimating a transmit signal quality value based on the correlation.

11. An apparatus for wireless communication, comprising:

a memory; and

at least one processor coupled to the memory and configured to;

correlate the feedback signal to a reference transmit signal to correct time misalignments between the transmit chain and the feedback loop, wherein the reference transmit signal is generated in digital domain at an input to a transmit chain; and

estimate a transmit signal quality value based on the correlation.

12. The apparatus of claim 11, wherein the processor is further configured to determine a feedback receiver response compensation based on feedback signal response to the reference transmit signal.

13. The apparatus of claim 12, wherein the processor is further configured to calculate a relative time delay between the feedback receiver and a transmitter of the transmit chain.

14. The apparatus of claim 11, wherein the transmit signal quality value comprises an error vector magnitude (EVM).

15. The apparatus of claim 11, wherein the transmit signal quality value comprises an adjacent channel leakage ratio.

16. A computer program product, comprising:

a computer-readable medium comprising executable code for;

correlating the feedback signal to a reference transmit signal to correct time misalignments between the transmit chain and the feedback loop, wherein the reference transmit signal is generated in digital domain at an input to a transmit chain; and

estimating a transmit signal quality value based on the correlation.