32-bit DSP implementation of Space-Time mobile channel simulator

Using multiple antennas in wireless links is currently being considered by a variety of standardisation bodies including the 3^rd Generation Partnership Project (3GPP) for the High Speed Downlink Packet Access (HSDPA) services. The field has matured substantially in recent years, both in theory and practice, with a growing awareness of the huge performance gains possible with Space-Time (ST) diversity techniques. As part of the drive towards successful evaluation of practical systems there is a requirement for flexible, low cost, and accurate models of the highly complex channel in which these systems must operate. This paper presents a DSP implementation of a base-band ST channel simulators using a modified Jakes mode that has a very low cross correlation between different waveforms. The channel simulator presented has been developed for a combined DSP/PC environment where flexibility and accuracy and speed of the model were maintained. Providing the channel within the DSP environment is faster than using a standard PC, particularly if using a package such as MATLAB® to simulate a system, and much cheaper than a RF channel simulator. Further, by defining quantisation effects at input if the systems under test, it can easily be adapted to suit testing of a variety of systems.