Split band LPC based adaptive multi-rate GSM candidate

The European Telecommunications Standards Institute (ETSI) has launched a competition for a new mobile communications standard designed to provide better performance than the current GSM standard. This standard is to be called AMR for Adaptive Multi-Rate: the source and channel coding rates can be adapted depending on the state of the channel, thus providing optimal balance between them at any time. The University of Surrey has submitted a candidate for this competition through the Mobile VCE. This candidate was the only one amongst eleven to use a vocoder in the half-rate GSM channel instead of a CELP based coder. The testing which took place as part of the first stage of the competition has shown that this candidate was among the best. This paper presents the system submitted for the half-rate channel as well as the results of the testing.