Method for detecting short burst errors in LDPC system
View Patent ↗The present invention is a device for detecting short burst errors. The device includes a first signal input, wherein the first signal input is configured to receive a first signal. The device includes a second signal input, wherein the second signal input is configured to receive a second signal. The device includes a logic gate, wherein the logic gate is operable for receiving the first signal via the first signal input, receiving the second signal via the second signal input, and generating a logic output gate signal based on the received first signal and the second signal. Furthermore, the device includes a filter, wherein the filter is configured for receiving the logic output gate signal from the logic gate and generates a filter output signal based upon the received logic output gate signal, wherein the filter output signal is operable for flagging errors.
1. A method for detecting short burst errors, the method comprising:
receiving a signal, wherein the signal includes a soft input (La) and a soft output (Le), wherein receiving a signal is through at least one of a channel detector or a low-density parity-check (LDPC) code decoder to detect short burst errors;
checking the signal for sign disagreement, wherein checking for sign disagreement includes checking a soft input sign(La) and a soft output sign(Le) for disagreement;
generating a sign disagreement, wherein a generated disagreement sign is sign(La)≠sign(Le) where the soft output sign(Le) fails to converge with the soft input sign(La);
passing the sign disagreement (La)≠(Le) through a filter, wherein the filter is a moving average filter which includes a moving average window configured for generating an averaged sign;
setting a burst threshold for the moving average window;
generating an erasure flag when the burst threshold is exceeded; and
extending erasure edges, wherein the erasure edges are extended left and right of the burst threshold by a maximum number of bits until a zero in the averaged sign is found.
2. The method of claim 1 , further comprising:
interleaving the disagreement sign(La)≠sign(Le).
3. A system, comprising:
a receiver;
a detector, the detector in communication with the receiver, the detector configured to detect short burst errors in a low-density parity-check (LDPC) code decoder; and
a signal processor configured for correcting burst errors, wherein the detector is configured to:
receive a signal, wherein the signal includes a soft input (La) and a soft output (Le);
check the signal for sign disagreement including to check a soft input sign(La) and a soft output sign(Le) for disagreement;
generate a sign disagreement, wherein a generated disagreement sign is sign(La)≠sign(Le) where the soft output sign(Le) fails to converge with the soft input sign(La);
pass the sign disagreement (La)≠(Le) through a filter, wherein the filter is a moving average filter which includes a moving average window configured to generate an averaged sign;
set a burst threshold for the moving average window;
generate an erasure flag when the burst threshold is exceeded; and
extend erasure edges, wherein the erasure edges are extended left and right of the burst threshold by a maximum number of bits until a zero in the averaged sign is found.
4. The system of claim 3 , further comprising:
an interleaver for interleaving the disagreement sign(La)≠sign(Le).