MSK-TYPE SIGNALS IN THE PRESENCE OF ADJACENT CHANNEL INTERFERENCE ANDWHITE-NOISE

In this letter, tile problem of adjacent channel interference (ACI) ca used by the close packing of constant envelope MSK-type users in a giv en frequency band is considered, tin optimal receiver filter, based on the theory of matched filtering, is found, and it serves as an upper bound on tile signal-to-interference ratio, Thf intersymbol inteferenc e (ISI) caused by the time response of the matched filter is eliminate d by a decision feedback equalizer (DFE) which, however, degrades perf ormance. It was found that the matched-filter upper bound allows about 3-15 dB more ACI than the performance of a classical correlation dete ctor for additive white Gaussian noise only), depending on the frequen cy separation between channels, The DFE performance is only a little b it worse than that of the matched filter.