Wireless communications apparatus

A MIMO detector is disclosed, for detecting information on a packet based signal comprising a header and one or more data symbols. The detector comprises header processing means 12 to determine channel decoding information QH, R, T and data processing means 14 operable, on the basis of the channel decoding information, to detect data in said one or more data symbols y. The R component (and optionally a QH component) output by QR decomposition means of the header processing means is used by the data processing means as channel decoding information. The header processing means also includes lattice reduction means for deriving reduced lattice channel state information T on the basis of said R component, and control means operable to determine if said lattice reduction means is to be employed. The control means are shown in Fig. 12. The control means may take into account factors such as latency (e.g. based on the number of data symbols received with a header) and the relative packet error rates (PER) associated with lattice-reduction aided detection in contrast to non-lattice-reduction aided detection.