An effective LMS equalizer for the GSM chipset

An effective equalization approach to implementing receivers for Global System for Mobile communications (GSM) is presented. The approach utilizes a linear transversal filter using an Least Mean Square (LMS) algorithm for tap coefficient training. Effective soft decision variables are generated from the output of the LMS equalizer. It is well known that an LMS equalizer has low complexity and can be easily implemented into an Application Specific Integrated Circuit (ASIC). Performance comparisons with 16-state Viterbi equalization are included. This approach is incorporated into CommQuest’s GSM chipset design for GSM receivers using its Communication Application Specific Processor (CASP®)technology.