Method and system for determining synchronization status in a wide band CDMA network

• US 8,626,226 B2
• Filed: 10/05/2010
• Issued: 01/07/2014
• Est. Priority Date: 02/15/2006
• Status: Active Grant

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Broadcom Corporation (Broadcom, Inc.)
• Inventors: Catreux-Erceg, Severine, Kent, Mark, Landau, Uri M, Erceg, Vinko
• Primary Examiner(s): GESESSE, TILAHUN
• Application Number:
  US12/897,972
• Publication Number:
  US 20110019727A1
• Time in Patent Office: 1,190 Days
• Field of Search: 455/522, 455/69, 455/127.1
• US Class Current: 455/522
• CPC Class Codes: H04W 52/241 taking into account channel quality metrics, e.g. SIR, SNR, CIR, Eb/lo
• CPC Class Codes: H04W 52/44 in connection with interruption of transmission
• CPC Class Codes: H04W 52/56 Detection of errors of TPC bits

Abstract

A method and system for determining synchronization status in a wide band CDMA (WCDMA) network may comprise calculating a signal to noise ratio (SNR) of a downlink dedicated physical channel (DPCH) based on a plurality of transmit power control (TPC) bits received via the downlink dedicated physical channel (DPCH), wherein the value of at least one of the plurality of TPC bits is not known when at least one of the plurality of TPC bits is received. The transmit circuitry may be controlled based on the calculated signal to noise ratio. The transmit circuitry may be disabled if the calculated SNR of the plurality of TPC bits is below a first channel threshold. The transmit circuitry may be enabled if the calculated SNR of the plurality of TPC bits is above a second channel threshold.

Claims

1. A method for signal processing, the method comprising:

for each of a plurality of radio links, calculating, using a processing unit, a signal to noise ratio (SNR) of a downlink dedicated physical channel (DPCH) based on a plurality of transmit power control (TPC) bits received via a plurality of multipaths over said DPCH,

wherein said calculating said SNR comprises summing portions of said plurality of TPC bits that are received via said plurality of multipaths over said DPCH to generate an in-phase (I) component and a quadrature (Q) component; and

calculating, using the processing unit an average SNR of said DPCH by averaging said calculated SNR of each of said plurality of radio links.

2. The method according to claim 1, further comprising controlling a transmit circuitry based on said calculated average SNR.

3. The method according to claim 1, further comprising disabling a transmit circuitry, if said calculated average SNR of said plurality of TPC bits is below a first channel threshold.

4. The method according to claim 1, further comprising enabling a transmit circuitry, if said calculated average SNR of said plurality of TPC bits is above a second channel threshold.

5. The method according to claim 1, wherein said calculating said SNR further comprises:

summing said generated I component and said generated Q component; and

squaring said summed said generated I component and said generated Q component to determine signal power of said DPCH.

6. The method according to claim 5, wherein said calculating said SNR further comprises calculating a norm of said squared said summed said generated I component and said generated Q component by dividing said squared said summed said generated I component and said generated Q component by a number of said plurality of TPC bits per slot of said DPCH to determine said signal power of said DPCH.

7. The method according to claim 6, wherein said calculating said SNR further comprises averaging said norm of said squared said summed said generated I component and said generated Q component over a time window.

8. The method according to claim 1, wherein said calculating said SNR further comprises subtracting said generated I component and said generated Q component to determine noise power of said DPCH.

9. The method according to claim 8, wherein said calculating said SNR further comprises:

squaring said subtracted said generated I component and said generated Q component; and

summing said squared said subtracted said generated I component and said generated Q component over a plurality of TPC symbols to determine said noise power of said DPCH.

10. The method according to claim 9, wherein said plurality of TPC symbols is half of said plurality of TPC bits per slot of said DPCH.

11. The method according to claim 9, wherein said calculating said SNR further comprises:

calculating a norm of said summed said squared said subtracted said generated I component and said generated Q component by dividing said summed said squared said subtracted said generated I component and said generated Q component by a number of said plurality of TPC bits per slot of said DPCH; and

averaging said norm of said summed said squared said subtracted said generated I component and said generated Q component over a time window to determine said noise power of said DPCH.

12. The method according to claim 1, further comprising enabling a transmit circuitry, if and only if at least one of said SNRs of said plurality of radio links is above a first channel threshold.

13. A system for signal processing, the system comprising:

one or more circuits that are configured to;

for each of a plurality of radio links, calculate a signal to noise ratio (SNR) of a downlink dedicated physical channel (DPCH) based on a plurality of transmit power control (TPC) bits received via a plurality of multipaths over said DPCH,

wherein said calculating said SNR comprises summing portions of said plurality of TPC bits that are received via said plurality of multipaths over said DPCH to generate an in-phase (I) component and a quadrature (Q) component; and

calculating an average SNR of said DPCH by averaging said calculated SNR of each of said plurality of radio links.

14. The system according to claim 13, wherein said one or more circuits are further configured to control a transmit circuitry based on said calculated average SNR.

15. The system according to claim 13, wherein said one or more circuits are further configured to disable a transmit circuitry, if said calculated average SNR of said plurality of TPC bits is below a first channel threshold.

16. The system according to claim 13, wherein said one or more circuits are further configured to enable a transmit circuitry, if said calculated average SNR of said plurality of TPC bits is above a second channel threshold.

17. The system according to claim 13, wherein said one or more circuits are configured to:

sum said generated I component and said generated Q component; and

square said summed said generated I component and said generated Q component to determine signal power of said DPCH.

18. The system according to claim 17, wherein said one or more circuits are configured to calculate a norm of said squared said summed said generated I component and said generated Q component by dividing said squared said summed said generated I component and said generated Q component by a number of said plurality of TPC bits per slot of said DPCH to determine said signal power of said DPCH.

19. The system according to claim 18, wherein said one or more circuits are configured to average said norm of said squared said summed said generated I component and said generated Q component over a time window.

20. The system according to claim 13, wherein said one or more circuits are configured to subtract said generated I component and said generated Q component to determine noise power of said DPCH.

21. The system according to claim 20, wherein said one or more circuits are configured to:

square said subtracted said generated I component and said generated Q component; and

sum said squared said subtracted said generated I component and said generated Q component over a plurality of TPC symbols to determine said noise power of said DPCH.

22. The system according to claim 21, wherein said plurality of TPC symbols is half of said plurality of TPC bits per slot of said DPCH.

23. The system according to claim 21, wherein said one or more circuits are configured to:

calculate a norm of said summed said squared said subtracted said generated I component and said generated Q component by dividing said summed said squared said subtracted said generated I component and said generated Q component by a number of said plurality of TPC bits per slot of said DPCH to determine said noise power of said DPCH; and

average said norm of said summed said squared said subtracted said generated I component and said generated Q component over a time window.

24. The system according to claim 13, wherein said one or more circuits are configured to enable a transmit circuitry if and only if at least one of said SNRs of said plurality of radio links is above a first channel threshold.