Title :
A fast algorithm for maximum likelihood detection of QPSK or π/4-QPSK sequences with unknown phase
Abstract :
Maximum likelihood sequence detection (MLSD) of differentially encoded MPSK uses a joint decision on N symbols to achieve a performance gain over conventional 2 symbol differential detection. This paper gives a fast (optimum) algorithm to implement MLSD; the number of operations per N symbol block is of order N log2 N. Thus, it is practical to implement MLSD for any reasonable N for moderate symbol rates; this is useful for the land mobile satellite and digital cellular channels
Keywords :
computational complexity; demodulation; digital radio systems; maximum likelihood estimation; mobile radio systems; phase shift keying; telecommunication channels; π/4-QPSK sequences; AWGN channel; QPSK sequences; algorithm complexity; differentially encoded MPSK; digital cellular channels; fast algorithm; land mobile satellite channels; maximum likelihood sequence detection; performance gain; unknown phase; AWGN channels; Additive white noise; Demodulation; Equations; Fading; Maximum likelihood detection; Performance gain; Phase detection; Quadrature phase shift keying; Satellites;
Conference_Titel :
Personal, Indoor and Mobile Radio Communications, 1992. Proceedings, PIMRC '92., Third IEEE International Symposium on
Conference_Location :
Boston, MA
Print_ISBN :
0-7803-0841-7
DOI :
10.1109/PIMRC.1992.279928
