Method and apparatus for providing fast detection of a high speed shared control channel

• US 20050180344A1
• Filed: 07/30/2004
• Published: 08/18/2005
• Est. Priority Date: 02/13/2004
• Status: Active Grant

• Current Assignee: Interdigital Technology Corporation (InterDigital, Inc.)
• Original Assignee: Interdigital Technology Corporation (InterDigital, Inc.)
• Inventors: Pietraski, Philip J., Tsai, Yingming, Sternberg, Gregory S.
• Granted Patent: US 7,054,288 B2
• Time in Patent Office: Days
• US Class Current: 370/310
• CPC Class Codes: H03M 13/3738 with judging correct decoding
• CPC Class Codes: H03M 13/41 using the Viterbi algorithm or Viterbi processors
• CPC Class Codes: H03M 13/653 3GPP HSDPA, e.g. HS-SCCH or DS-DSCH related
• CPC Class Codes: H04L 1/0054 Maximum-likelihood or sequential decoding, e.g. Viterbi, Fano, ZJ algorithms
• CPC Class Codes: H04L 1/0072 Error control for data other than payload data, e.g. control data
• CPC Class Codes: H04L 1/20 using signal quality detector

Abstract

A method and apparatus for providing fast detection of a high speed shared control channel (HS-SCCH). The HS-SCCH carries information necessary for receiving data via a high speed downlink shared channel (HS-DSCH). The apparatus receives messages transmitted via a plurality of HS-SCCHs. The apparatus measures a channel quality for the messages received via each HS-SCCH. The apparatus performs a threshold test by comparing the channel quality with a predetermined threshold. The apparatus then selects a HS-SCCH having the best channel quality among the HS-SCCHs.

Claims

1. A method for providing fast detection of a high speed shared control channel (HS-SCCH), the method comprising:

(a) receiving messages transmitted via a plurality of HS-SCCHs;

(b) estimating a channel quality of the messages received via each HS-SCCH;

(c) comparing the channel quality of each message with a threshold; and

(d) selecting a HS-SCCH having the highest channel quality among the HS-SCCHs.

2. The method of claim 1 wherein the channel quality estimation is performed by calculating a bit error rate (BER).

3. The method of claim 1 further comprising the steps of:

(e) decoding the messages which are encoded by convolutional encoding;

(f) generating an accumulated soft metric; and

(g) comparing the accumulated soft metric with a soft metric threshold; and

(h) selecting a HS-SCCH having the lowest accumulated soft metric among HS-SCCHs having an accumulated soft metric lower than the soft metric threshold.

4. The method of claim 3 wherein, when more than one soft metric exceeds the soft metric threshold and are close in value, preference is given to one of the soft metrics if it had been previously used on the last received message.

5. The method of claim 1 wherein the HS-SCCH transmits information necessary to receive data via a high speed downlink shared channel (HS-DSCH), and the HS-SCCH and the HS-DSCH are transmitted with a predetermined timing offset each other.

6. The method of claim 5 wherein the HS-SCCH and the HS-DSCH comprises a three time slot frame and are transmitted with one time slot overlapping each other, and the channel quality is estimated for the messages received on the first time slot of the HS-SCCH.

7. A wireless transmit/receive unit (WTRU) for providing fast detection of a high speed shared control channel (HS-SCCH), the WTRU comprising:

a plurality of receivers for receiving messages via a plurality of HS-SCCHs;

a channel quality estimator for estimating a channel quality for the messages received via each HS-SCCH;

a threshold comparator for comparing the channel quality estimate with a threshold; and

,

a selector for selecting a HS-SCCH having a highest channel quality estimate among the HS-SCCHs.

8. The WTRU of claim 7 wherein the channel quality estimation is performed by calculating a bit error rate (BER).

9. The WTRU of claim 7 wherein each receiver comprises a decoder for decoding messages which are encoded by convolutional encoding.

10. The WTRU of claim 9 wherein the decoder generates an accumulated soft metric, the threshold comparator compares the accumulated soft metric with a soft metric threshold, and the selector selects a HS-SCCH having the lowest accumulated soft metric among the HS-SCCHs.

11. The WTRU of claim 10 wherein, when more than one soft metric exceeds the soft metric threshold and are close in value, preference is given to one of the soft metrics if it had been previously used on the last received message.

12. The WTRU of claim 7 wherein the HS-SCCH transmits information necessary to receive data via a high speed downlink shared channel (HS-DSCH), and the HS-SCCH and the HS-DSCH are transmitted with a predetermined timing offset each other.

13. The WTRU of claim 12 wherein the HS-SCCH and the HS-DSCH comprises a three time slot frame and are transmitted with one time slot overlapping each other, and the channel quality is estimated for the messages received on the first time slot of the HS-SCCH.

14. An integrated circuit (IC) for providing fast detection of a high speed shared control channel (HS-SCCH), the IC comprising:

a plurality of receivers for receiving messages via a plurality of HS-SCCHs;

a channel quality estimator for estimating a channel quality for the messages received via each HS-SCCH;

a threshold comparator for comparing the channel quality estimate with a threshold; and

,

a selector for selecting a HS-SCCH having a highest channel quality estimate among the HS-SCCHs.

15. The IC of claim 14 wherein the channel quality estimation is performed by calculating a bit error rate (BER).

16. The IC of claim 14 wherein each receiver comprises a decoder for decoding messages which are encoded by convolutional encoding.

17. The IC of claim 14 wherein the decoder generates an accumulated soft metric, the threshold comparator compares the accumulated soft metric with a soft metric threshold, and the selector selects a HS-SCCH having the lowest accumulated soft metric among the HS-SCCHs.

18. The IC of claim 15 wherein, when more than one soft metric exceeds the soft metric threshold and are close in value, preference is given to one of the soft metrics if it had been previously used on the last received message.

19. The IC of claim 14 wherein the HS-SCCH transmits information necessary to receive data via a high speed downlink shared channel (HS-DSCH), and the HS-SCCH and the HS-DSCH are transmitted with a predetermined timing offset each other.

20. The IC of claim 19 wherein the HS-SCCH and the HS-DSCH comprises a three time slot frame and are transmitted with one time slot overlapping each other, and the channel quality is estimated for the messages received on the first time slot of the HS-SCCH.