System model for performance evaluation VAMOS downlink transmission

The Voice services over Adaptive Multiuser channels on One Slot (VAMOS) feature has the potential to double voice capacity of the existing GSM mobile communication system while maintaining backward compatibility with the legacy system. The technical method of doubling voice channel capacity is based on Orthogonal Sub-Channel (OSC) approach that allows a single radio resource to support two independent voice users. Lot of research work is dedicated to signal generation and especially to new receiver concepts as well as power control in order to implement VAMOS transmissions. The aim of our work is to implement a model system able to evaluate performance parameters related to downlink transmission in VAMOS. The model implements generation of the VAMOS modulated signal with power control and receiving solutions based on a modified DFE (Decision Feedback Equalizer) structure that allows comparison of performances in VAMOS downlink transmission.