GSM radio link simulation

The forthcoming Pan-European Digital Cellular Radio System (usually known as the GSM system) will employ TDMA with eight channels per carrier, at an aggregate bit rate of about 270 kb/s. Such a bit rate requires a channel coherence bandwidth which is often not available in the mobile radio environment. Typical dispersion levels (i.e. 6-8 μs delay window in an urban environment) will result in significant intersymbol interference, which can be combatted by using equalisers. The author reports some work and performance results related to equaliser algorithms for GSM based on the Viterbi Algorithm (VA). The emphasis is on specific aspects such as the reduction of equaliser complexity and the combined effect of equalisation and diversity