Radio link performance prediction in wireless communication terminal

• US 8,442,021 B2
• Filed: 10/26/2009
• Issued: 05/14/2013
• Est. Priority Date: 11/07/2008
• Status: Active Grant

• Current Assignee: Google Technology Holdings LLC (Alphabet Inc.)
• Original Assignee: Motorola Mobility LLC (Lenovo Group Ltd.)
• Inventors: Krishnamurthy, Sandeep, Kuchibhotla, Ravi
• Primary Examiner(s): Pham, Chi
• Assistant Examiner(s): Faroul, Farah
• Application Number:
  US12/605,461
• Publication Number:
  US 20100122121A1
• Time in Patent Office: 1,296 Days
• Field of Search: 370/342, 370/350, 370/48, 370/704, 370/707
• US Class Current: 370/342
• CPC Class Codes: H04L 1/0016 involving special memory structures, e.g. look-up tables
• CPC Class Codes: H04L 1/0026 Transmission of channel quality indication
• CPC Class Codes: H04L 1/20 using signal quality detector
• CPC Class Codes: H04W 24/02 Arrangements for optimising operational condition

Abstract

A method for predicting performance of a radio link in a wireless communication terminal including hypothesizing a second codeword including information associated with a hypothesized first codeword, obtaining channel state information from a received signal, and estimating a decoder error rate of the first codeword under a condition that the second codeword may not be decoded correctly, wherein the decoder error rate is estimated using the channel state information.

Claims

1. A method for predicting the performance of radio link in a wireless communication terminal, the method comprising:

hypothesizing a first codeword, wherein the first codeword corresponds to a control channel;

hypothesizing a second codeword, wherein the second codeword corresponds to a control format indicator channel carrying information related to transmission parameters of the control channel;

receiving a reference signal;

estimating a decoder error rate of the first codeword under a condition that the second codeword may not be decoded correctly, the decoder error rate is estimated based on the reference signal.

2. The method of claim 1, wherein the received reference signal corresponds to a cell-specific reference signal.

3. The method of claim 1 further comprising determining a synchronization status of the radio link based upon the estimated decoder error rate of the first codeword.

4. The method of claim 1 further comprising generating channel quality indication reports based on the estimated decoder error rate for the first codeword.

5. The method of claim 1, wherein the transmission parameters correspond to any one of:

a number of symbols on which the first codeword is mapped,

time-frequency resources on which the first codeword is mapped, or

an encoding method used for generating the first codeword, or

an information size of a payload of the first codeword, or

a block length of the first codeword, or

a rate of the first codeword, or

a redundancy version number of the first codeword, or

a transmit antenna configuration used for the first codeword or

pre-coding used for the first codeword.

6. The method of claim 1 further comprising

hypothesizing a third codeword including information associated with the second codeword;

estimating the decoder error rate of the first codeword under a condition that the second and third codewords may not be decoded correctly.

7. The method of claim 6 further comprising generating channel quality indication reports based on the estimated decoder error rate for the first codeword.

8. The method of claim 6, wherein the information included in the third code word is a transmission parameter corresponding to any one of:

a number of symbols on which the second codeword is mapped,

time-frequency resources on which the second codeword is mapped, or

an encoding method used for generating the second codeword, or

an information size of a payload of the second codeword, or

a block length of the second codeword, or

a rate of the second codeword, or

a redundancy version number of the first codeword, or a transmit antenna configuration used for the second codeword or

pre-coding used for the second codeword.

9. The method of claim 1, further comprising:

based on the received reference signal, estimating the probability of error in decoding the hypothesized second codeword

based on the received reference signal, estimating the probability of error in decoding the first codeword correctly, conditioned upon the second codeword being decoded correctly;

estimating the decoder error rate of the first codeword based on;

the probability of error in decoding the first codeword correctly, conditioned upon the second codeword being decoded correctly and the estimated probability of error in decoding the hypothesized second codeword.

10. The method of claim 9, wherein the decoder error rate of the first codeword is a probability of error in decoding the first codeword, and wherein the probability of error in decoding the first codeword is estimated using the equation:

p_e(CW₂)=1−

(1−

p_e(CW₁))(1−

p_e(CW₂|CW₁ correctly decoded)) , wherein

p_e(CW₁) is the probability of error in decoding the first codeword CW₁,

p_e(CW₂) is the probability of error in decoding the second codeword CW₂,

p_e (CW₁|CW₂ correctly decoded) is the probability of error in decoding the first codeword correctly, conditioned upon the second codeword being decoded correctly.

11. A wireless communication terminal comprising:

a transceiver configured to receive a reference signal;

a controller coupled to the transceiver,

the controller configured to hypothesize a first codeword and to hypothesize a second codeword,

wherein the first codeword corresponds to a control channel and the second codeword corresponds to a control format indicator channel carrying information related to transmission parameters of the control channel,

the controller configured to estimate a decoder error rate of the first codeword under a condition that the second codeword is not decoded correctly, the decoder error rate is estimated based on the reference signal.

12. The terminal of claim 11, the controller configured to determine synchronization status of the radio link based upon the estimated decoder error rate of the first codeword.

13. The method of claim 11, the controller configured to generate channel quality indication reports based on the estimated decoder error rate for the first codeword.

14. The terminal of claim 11, wherein the transmission parameters corresponding to any one of:

a number of symbols on which the first codeword is mapped,

time-frequency resources on which the first codeword is mapped, or

an encoding method used for generating the first codeword, or

an information size of a payload of the first codeword, or

a block length of the first codeword, or

a rate of the first codeword, or

a redundancy version number of the first codeword, or

a transmit antenna configuration used for the first codeword or

pre-coding used for the first codeword.

15. The terminal of claim 11, the controller configured to hypothesize a third codeword including information associated with the second codeword and to estimate the decoder error rate of the first codeword under a condition that the second and third codewords are not decoded correctly.

16. The terminal of claim 15, the controller configured to generate channel quality indication reports based on the estimated decoder error rate for the first codeword.

17. The terminal of claim 15, the information included in the third code word is a transmission parameter corresponding to any one of:

a number of symbols on which the second codeword is mapped,

time-frequency resources on which the second codeword is mapped, or

an encoding method used for generating the second codeword, or

an information size of a payload of the second codeword, or

a block length of the second codeword, or

a rate of the second codeword, or

a redundancy version number of the first codeword, or

a transmit antenna configuration used for the second codeword or

pre-coding used for the second codeword.