Receive Diversity and LMMSE Equalization Benefits for HSDPA: Realistic Network Throughputs

The HS-DSCH uses multicodes which are orthogonal at the Node B but passing through a frequency selective channel this property is lost and MAI arises. To mitigate these interferences, advanced receivers are needed. The chip level teast-minimum-mean-square-error (LMMSE) equalizer for a single receiver antenna and a space time TMMSE one for receiver diversity are considered. The HSDPA throughputs are evaluated on a network simulator using realistic propagation model, a real town topography, radio sites actual locations and real antenna settings. Simulation results show that using only one receiver antenna leads to 20% of the area achieving a throughput higher than 1.5 Mbps. However, the receiver diversity increases this rate above 90%. The Rake with receiver diversity enables 40% of area to achieve 2 Mbps and the space-time LMMSE increases this rate above 60%.