The invention belongs to the field of
wireless communication and relates to an incoherent detection technology suitable for a DMR (
Digital Mobile Radio) digital
trunking communication
system. Firstly, defects of both a conventional incoherent detection technology and an existing multiple symbol detection
algorithm are analyzed in detail; then according to the maximum likelihood ratio criterion, an incoherent multiple symbol detection
algorithm suitable for a 4-CPFSK (Continuous Phase
Frequency Shift Keying)
signal in a DMR standard frame is disclosed; and simultaneously, a decomposed linear
signal replaces an original reference
signal to simplify the structure of a
receiver. The
receiver corresponding to the
algorithm disclosed by the invention is formed by three front-end matched filters and a following viterbi operational part and the complexity of the
receiver is effectively reduced. When the calculation of the
branch metric is carried out, the judgment accuracy is improved by utilizing information of a plurality of pieces of code element time. A
computer simulation result in the
Matlab environment proves that with the increase of observing windows, the performance of detecting the 4-CPFSK signal of the algorithm disclosed by the invention gradually becomes better.