Linear combinations of transmit signals by a receiver

A multi-port transmitter can synthesize and send a first plurality of transmit signals having a separability characteristic which permits them to be differentiated from one another. A receiver can then detect one or more receiver signals which include one or more combinations of received versions of the first plurality of transmit signals. The receiver may use the separability characteristic to determine the received versions of the first plurality of transmit signals from the one or more receiver signals. Then, the receiver may determine an estimated signal corresponding to the estimated receiver response to a second plurality of virtual transmit signals which comprise a combination of the first plurality of transmit signals. Determining the estimated signal may include forming a combination of the received versions of the first plurality of transmit signals.