Orthogonal and projected orthogonal matched filter detection

This paper considers the generic problem of detecting in the presence of additive noise, which one from a set of known signals has been received. In place of the classical matched #lter (MF) receiver we propose a modi#ed receiver. When the transmitted signals are linearly independent this receiver is referred to as an orthogonal matched #lter (OMF) receiver, and when the transmitted signals are linearly dependent it is referred to as a projected orthogonal matched #lter (POMF) receiver. Two equivalent representations of the receiver are developed with di<erent implications in terms of implementation. In the #rst, the demodulator consists of a MF demodulator followed by an optimal whitening transformation on a space formed by the transmitted signals, that optimally decorrelates the MF outputs prior to detection. In the second, the demodulator consists of a bank of correlators with correlating signals that are projections of a set of orthogonal signals, and are closest in a least-squares sense to the transmitted signals. We provide simulation results that suggest that in certain cases the OMF and POMF receivers can signi#cantly increase the probability of correct detection over the MF receiver in non-Gaussian noise with only a minor impact on performance in Gaussian noise. ? 2003 Elsevier B.V. All rights reserved.