Method for control channel detection in wireless communications systems

1. A method of detecting a control channel, comprising:

receiving data transmitted via a control channel;

computing a path metric based on the received data;

computing a correction term based on the received data;

computing a decision metric representing a sum or a difference of the path metric and the correction term; and

deciding, based on the decision metric, on a detection of the control channel,

wherein deciding on a detection of the control channel comprises comparing the decision metric to a threshold and deciding on a detection based on a result of the comparison.

2. The method of claim 1 , wherein computing the path metric comprises computing a maximum likelihood path metric based on the received data.

3. The method of claim 1 , wherein computing the path metric comprises computing an accumulated path metric based on the received data.

4. The method of claim 1 , wherein computing the path metric comprises computing a Viterbi path metric based on the received data.

5. The method of claim 1 , wherein computing the path metric further comprises multiplying the path metric with a weighting factor indicative of a signal strength of the received data.

6. The method of claim 1 , wherein the correction term is indicative of a signal strength of the received data.

7. The method of claim 1 , wherein computing the correction term comprises performing a summing operation on vector elements of a received soft-bit data vector.

8. The method of claim 7 , wherein the summing operation comprises applying a first function on each vector element.

9. The method of claim 8 , wherein the first function comprises one or more of a multiplication with a weighting factor, a logarithm, a hyperbolic cosine, an absolute value function, and a squaring function, or approximations thereof.

10. The method of claim 1 , wherein the path metric and the correction term are computed in parallel.

11. A method of selecting a control channel from a plurality of control channels, comprising:

receiving data transmitted via the plurality of control channels;

computing, based on the received data, a path metric and a correction term for each of the plurality of control channels;

computing, for each of the plurality of control channels, a decision metric representing a sum or a difference of the path metric and the correction term; and

selecting, based on the plurality of computed decision metrics, a control channel from the plurality of control channels, wherein selecting a control channel comprises:

comparing each of the plurality of computed decision metrics to a threshold, and

selecting the control channel based on those decision metrics which passed the comparison.

12. The method of claim 11 , wherein computing the decision metric comprises applying a channel-specific weighting factor to at least one of the path metric and the correction term.

13. The method of claim 12 , wherein the weighting factor represents a channel-specific signal strength.

14. The method of claim 13 , wherein the weighting factor represents a channel-specific signal amplitude and/or a channel-specific signal variance of the received data.

15. The method of claim 13 , wherein the weighting factor comprises a function representing a signal-to-noise ratio and/or a signal power of a corresponding control channel.

16. The method of claim 15 , wherein the weighting factor comprises an inverse of the function or of a square root of the function or another function x p where x is the function and p is any real number.

17. The method of claim 13 , wherein selecting a control channel comprises selecting a High Speed Shared Control Channel (HS-SCCH) in a High Speed Downlink Packet Access (HSDPA) system.

18. A computer program product having computer executable instructions stored in a non-transitory storage medium, and upon executing the instructions in conjunction with a processor, operable to perform a method, comprising:

receiving data transmitted via the plurality of control channels at a receiver circuit;

computing, based on the received data, a path metric and a correction term for each of the plurality of control channels using a processor circuit;

computing, for each of the plurality of control channels, a decision metric representing a sum or a difference of the path metric and the correction term using the processor circuit; and

selecting, based on the plurality of computed decision metrics, a control channel from the plurality of control channels, wherein selecting a control channel comprises:

comparing each of the plurality of computed decision metrics to a threshold, and

selecting the control channel based on those decision metrics which passed the comparison.

19. A device for detecting a control channel, comprising:

a first component configured to receive data transmitted via a control channel;

a second component configured to compute a path metric based on the received data;

a third component configured to compute a correction term based on the received data;

a fourth component configured to compute a decision metric representing a sum or a difference of the path metric and the correction term; and

a fifth component configured to decide, based on the decision metric, on a detection of the control channel,

wherein deciding on a detection of the control channel comprises comparing the decision metric to a threshold and deciding on a detection based on a result of the comparison.

20. A device for selecting a control channel from a plurality of control channels, comprising:

a first component configured to receive data transmitted via the plurality of control channels;

a second component configured to compute, based on the received data, a path metric and a correction term for each of the plurality of control channels;

a third component configured to compute a decision metric representing a sum or a difference of the path metric and the correction term for each of the plurality of control channels; and

a fourth component configured to select, based on the plurality of decision metrics, a control channel from the plurality of control channels, wherein selecting a control channel comprises:

comparing each of the plurality of computed decision metrics to a threshold, and

selecting the control channel based on those decision metrics which passed the comparison.

21. The device of claim 20 , wherein one or more of the components are implemented in firmware and/or hardware.