Patent ID: 8185811

Claim:
A method for joint erasure and Viterbi decoding, comprising: receiving data having a convolutional code trellis representation; generating a product trellis for the data by extending the convolutional code trellis representation into a bit trellis representation and obtaining the product trellis as a product of the bit trellis representation and an indicator trellis; truncating the product trellis by applying a sliding window to the product trellis; storing a surviving path for the erasure state from the sliding window; evaluating a subset of erasure states in the product trellis based on a predetermined number of erasures, the number of erasures is predetermined based on a number of impulses expected to impact the sliding window; calculating for the received data, at least one candidate code sequence and corresponding at least one state metric with at least one erasure having an erasure state; testing whether the at least one candidate code sequence satisfies at least one sufficiency criterion; and determining a subsequent iteration of the at least one candidate code sequence and corresponding at least one state metric for the data based on the calculated at least one state metric in response to the calculated at least one candidate code sequence not satisfying the at least one sufficiency criterion.