1. A method of receiving a signal in a telecommunication system, the method comprising: receiving, with one or more antennas, signals transmitted by one or more transmitters using a multitude of channels; selecting one or more channel pairs, each channel of each channel pair being at a given distance from each other; determining symbol estimates for the signals of the channels of the channel pairs; removing an effect of data modulation from the signals of the channels of the channel pairs; obtaining noise estimates by subtracting the signals of the channels of the channel pairs from each other; and determining a noise covariance matrix for a desired channel based on the obtained noise estimates.