and 502 of course there my be more than two collisions in a transmission such as three or more transmitters 14 attempting to send messages at the same time in this case the present invention will operate on all colliding messages and correct all overlapping signals in another embodiment of the present invention the content of the recovery message 504 consists of the retransmission of only the overlapping portion of data message 501 and data message 502 in this embodiment the content of both message 501 and 502 can be reconstructed using the overlapping portion from either message 501 or 502 in this case the changes in signal parameters timing phase carrier phase amplitude channel impulse response etc occurring between the time of the first transmission 501 502 and the time of the transmission of the recovery message 504 may be estimated and compensated to retrieve the original message the recovery message signal in its analog form is subtracted from the initially received analog signal so that the mutual interference is reduced and other signals that collided with the above signal may be detected those skilled in the art will readily recognize that the present invention may be used in a non collision based communication system where messages are corrupted by noise fading and other forms of interference in such a system the messages can be corrected with recovery messages.