Multiple Steiner codes are transmitted as bursts from multiple base stations (182, 184, 186) having one or more transmit elements (174, 176, 178, 180), with successive bursts providing an extended training sequence for use in channel 
estimation at an addressed unit (172), such as a mobile 
handset. Accurate channel 
estimation is possible through the use of Wiener 
frequency domain MMSE 
deconvolution (518) combined with 
frequency domain spatial decoupling matrices, with quasi-orthogonal pseudo-
noise sequences (502, 504, 520, 522) allocated to base stations and their antenna elements. The use of Steiner codes to supplement Wiener 
frequency domain MMSE 
deconvolution and frequency domain spatial decoupling results in the possibility of allocating only a single training sequence to each 
base station provided that the training sequence is of sufficient length to encompass all multiple time-translated channel impulse responses (H). Estimates may be refined iteratively by minimising the MS error of demodulated 
pilot symbols. Estimates may also be refined by removing taps from the 
impulse response which are insignificant based on a relatively long-term power-
delay profile for the channel.