Method for controlling decoding process based on path metric value and computing apparatus and mobile device for controlling the same

1. A computing apparatus comprising:

a Viterbi decoder (VD) configured to decode a tail biting convolutional code (TBCC)-encoded data,

wherein the VD is configured to:

receive TBCC-encoded data;

select a candidate to initiate a training section;

determine final path metric (PM) values of possible states at a last step of the training section;

determine a minimum PM value from among the final PM values of the possible states;

determine a PM-related value based on the final PM values of the possible states; and

determine an early termination of a decoding for the candidate based on the PM-related value,

wherein the PM-related value comprises a normalized minimum PM value determined by the VD via normalization of the minimum PM value, and

wherein the VD is further configured to:

compare the PM-related value with a normalized PM threshold; and

determine the early termination in response to the PM-related value being greater than the normalized PM threshold.

2. The computing apparatus of claim 1 , wherein:

the PM-related value comprises a minimum PM value or a maximum PM value selected from among the final PM values of the possible states; and

wherein the VD is further configured to:

compare the PM-related value with a PM-related threshold; and

determine the early termination based on the comparison.

3. The computing apparatus of claim 1 , wherein the normalized PM threshold is determined based on a symbol error rate.

4. The computing apparatus of claim 1 , wherein the VD is further configured to:

determine a maximum PM value from among the final PM values of the possible states,

wherein the PM-related value comprises a normalized maximum PM value determined by the VD via normalization of the maximum PM value, and

wherein the VD is further configured to:

compare the PM-related value with a normalized PM threshold; and

determine the early termination in response to the PM-related value being smaller than the normalized PM threshold.

5. The computing apparatus of claim 1 , wherein the VD is further configured to:

determine a PM difference at a possible state that provides the minimum PM value at the last step;

compare the PM difference with a PM difference threshold; and

determine the early termination in response to the PM difference being smaller than the PM difference threshold.

6. The computing apparatus of claim 1 , wherein, in response to a determination not to perform the early termination, the VD is further configured to:

set the final PM values of the possible states as initial PM values of corresponding possible states, respectively, in a next training section or in a maximum likelihood (ML) path finding operation;

determine a survival path in the ML path finding operation;

perform a 16-bit Cyclic Redundancy Check (CRC) check based on data bits associated with the survival path; and

determine whether the candidate is a correct candidate based on the 16-bit CRC check.

7. The computing apparatus of claim 1 , wherein, in response to a determination to perform the early termination, the VD is further configured to:

stop the decoding for the candidate; and

initiate a training section for a next candidate.

8. The computing apparatus of claim 1 , wherein:

the TBCC-encoded data corresponds to Physical Downlink Control Channel (PDCCH) comprising Downlink Control Information (DCI); and

the VD is configured to perform a blind decoding for a plurality of candidates with respect to at least one of aggregation levels 1 , 2 , 4 , and 8 .

9. A method of controlling a decoding process of a tail biting convolutional code (TBCC)-encoded data in a decoder, the decoder configured to decode the TBCC-encoded data, the method comprising:

receiving, at a convolutional decoder, TBCC-encoded data;

selecting a candidate to initiate a training section;

determining final path metric (PM) values of possible states at a last step of the training section;

determining a PM-related value based on the final PM values of the possible states; and

determining an early termination of a decoding for the candidate based on the PM-related value,

wherein determining of the PM-related value comprises:

determining a minimum PM value from among the final PM values of the possible states; and

determining PM-related value as a normalized minimum PM value via normalization of the minimum PM value;

wherein determining the early termination comprises:

comparing the PM-related value with a normalized PM threshold; and

determining the early termination in response to the PM related value being greater than the normalized PM threshold.

10. A decoder to decode a tail biting convolutional code (TBCC)-encoded data, the decoder comprising:

a receiver to receive TBCC-encoded data;

a branch metric processor to determine branch metrics;

a path metric processor to determine final path metric (PM) values of possible states at a last step of a training section; and

a path metric analyzer to:

determine a minimum PM value from among the final PM values of the possible states;

determine a PM-related value based on the final PM values of the possible states; and

determine an early termination of a decoding for a candidate based on the PM-related value and a PM-related threshold,

wherein the PM-related value comprises a normalized minimum PM value determined by the VD via normalization of the minimum PM value, and

wherein the path metric analyzer is further configured to:

compare the PM-related value with a normalized PM threshold; and

determine the early termination in response to the PM-related value being greater than the normalized PM threshold.

11. The decoder of claim 10 , wherein:

the PM-related value comprises a minimum PM value or a maximum PM value selected from among the final PM values of the possible states; and

the path metric analyzer is configured to:

compare the PM-related value with the PM-related threshold; and

determine the early termination based on the comparison.

12. The decoder of claim 10 , wherein the PM-related threshold is determined based on a symbol error rate, the symbol error rate is in a range of 0.001% to 50%.

13. The decoder of claim 10 , wherein the path metric analyzer is further configured to:

determine a maximum PM value from among the final PM values of the possible states,

wherein the PM-related value comprises a normalized maximum PM value determined by the path metric analyzer via normalization of the maximum PM value, and

wherein the path metric analyzer is further configured to:

compare the PM-related value with the PM-related threshold; and

determine the early termination in response to the PM-related value being smaller than the PM-related threshold.

14. The decoder of claim 10 , wherein the path metric analyzer is further configured to:

determine a PM difference at a possible state that provides the minimum PM value at the last step;

compare the PM difference with the PM-related threshold; and

determine the early termination in response to the PM difference being smaller than the PM-related threshold.

15. The decoder of claim 10 , wherein, in response to a determination not to perform the early termination, the decoder is configured to:

set the final PM values of the possible states as initial PM values of corresponding possible states, respectively, in a next training section or in a maximum likelihood (ML) path finding operation;

determine a survival path in the ML path finding operation;

perform a 16-bit Cyclic Redundancy Check (CRC) check based on data bits associated with the survival path; and

determine whether the candidate is a correct candidate based on the 16-bit CRC check.

16. The decoder of claim 10 , wherein, in response to a determination to perform the early termination, the decoder is configured to:

stop the decoding for the candidate; and

initiate a training section for a next candidate.

17. The decoder of claim 10 , wherein:

the TBCC-encoded data corresponds to Physical Downlink Control Channel (PDCCH) comprising Downlink Control Information (DCI); and

the decoder is configured to perform a blind decoding for a plurality of candidates with respect to at least one of aggregation levels 1 , 2 , 4 , and 8 .

18. A mobile device comprising:

a display;

a mobile-communication modem comprising a Viterbi decoder (VD) configured to decode a tail biting convolutional code (TBCC)-encoded data;

a memory coupled to the mobile-communication modem; and

a wireless antenna coupled to the mobile-communication modem, the wireless antenna being configured to receive a Physical Downlink Control Channel (PDCCH),

wherein the VD is configured to:

receive TBCC-encoded data;

select a candidate to initiate a training section;

determine final path metric (PM) values of possible states at a last step of the training section;

determine a minimum PM value from among the final PM values of the possible states:

determine a PM-related value as a normalized minimum PM value via normalization of the minimum PM value;

compare the PM-related value with a normalized PM threshold; and

determine an early termination of a decoding for the candidate in response to the PM related value being greater than the normalized PM threshold.