Dual Antenna LMMSE Equalization in the Presence of Correlated Interference using Bad Urban Channel Data in HSDPA Multicode Transmission

This paper discusses WCDMA mobile terminal receivers that employ dual antenna LMMSE equalization in high speed downlink packet access (HSDPA) multicode transmission. The strong correlated inter-cell interference is a major concern for a mobile terminal in realistic cellular environments. In this paper the channel characteristics of the serving and interfering base stations are taken into account using the "bad urban" channel data measured simultaneously from several base stations. This enables us to verify how robust the receiver algorithms are against the single dominant correlated interference source. The considered receiver algorithms include two versions of LMMSE chip-equalizers that are compared against the MRC-RAKE receiver enhanced with finger-specific interference weighting. The simulation results demonstrate that the considered LMMSE chip-equalizers are robust solutions in the bad urban channel environment. At the critical region near the cell edge, performance differences between the space-time algorithms can be however noticed, depending on the type of the correlation matrix construction. We also show how the measured data can be utilized in the link performance analysis