Noncoherent Coded Modulation

Noncoherent coded modulation is the synthesis of forward error-correction coding for non-binary signaling with noncoherent detection techniques. Such a configuration naturally arises if power- and bandwidth-efficient communication is desired in a hostile fading channel environment.

In this thesis, noncoherent coded modulation for frequency-nonselective fading channels in the absence of channel state information (CSI) at the transmitter and at the receiver side is studied. Two particular approaches are investigated in detail, which are based on two different noncoherent detection strategies: multiple-symbol differential detection (MSDD) and decision-feedback differential detection (DFDD). The underlying principle of both MSDD and DFDD is to utilize an increased observation window size of N <2 consecutively received symbols to yield decision variables. In this way, the channel memory is more completely taken into account and consequently, power efficiency of noncoherent detection without CSI can be improved over conventional differential detection (CDD) with N = 2.