Patent attributes
The disclosed invention provides a method, a system and a computer program product for the maximum likelihood sequence estimation of transmitted MSK symbols. The disclosed invention provides a set of optimizations of the Viterbi algorithm for equalizing MSK symbols. The transmitted MSK symbols are alternately real and imaginary. Therefore, based on whether the transmitted MSK symbol is real or imaginary, the disclosed invention divides the set of Viterbi states into two sets of states. The disclosed invention obtains the surviving path only for the first set of states at stages corresponding to real transmitted symbols. A real hypothesis is used to obtain the surviving paths for the first set of states. The disclosed invention also obtains the surviving path only for the second set of states at stages corresponding to imaginary transmitted symbols. An imaginary hypothesis is used to obtain the surviving paths of the second set of states. Therefore, the Viterbi trellis is advanced by considering only half the number of Viterbi states at each stage, leading to computational efficiency.
