Results on fast-Kalman and Viterbi adaptive equalizers for mobile radio with CEPT/GSM system characteristics

The authors study the performance of adaptive equalizers using the complex fast-Kalman adaptation algorithm (CFKA) and of receivers using the maximum-likelihood sequence estimation method called the Viterbi algorithm in the framework of current research on the pan-European digital mobile radio system in the 900-MHz band. The CEPT/GSM (Conference Europeenne des Postes et Telecommunications/Groupe Special Mobile) system working assumptions, envisaging the use of a synchronization word or preamble sequence, are taken into account. Four types of propagation channels are considered. It is shown that a (2, 3) decision-feedback equalizer using the CFKA meets the CEPT/GSM objectives over the whole specified range of echo delays and also at high vehicle speeds (up to about 300 km/h), whereas the Viterbi equalizer can cope with the channel distortions produced by echo delays less than about 14-15 μm