Envelope-aided DFE equalisers for detection of GMSK with LD demodulation

Conventional decision feedback equalisation (DFE) is a common solution to the frequency selective multipath propagation problem that appears in high data rate radio communications because of its simplicity and good performance. However, when a limiter-discriminator (LD) is used for detection of GMSK signals, the global system has a nonlinear characteristic and conventional DFEs yield poor performance even for moderate delay-spread (DS) channels. An envelope-aided DFE equaliser is proposed that extends the use of GMSK with LD to high DS channels at a minimum increase in complexity and cost