Patent ID: 6917281

Claim:
A transmission method in a wireless communication system, the transmission method comprising the steps of: pre-programming each of a plurality of wireless communication units with a plurality of orthogonal codes corresponding to a plurality of canned messages, the plurality of orthogonal codes chosen such that when a group of different canned messages are received simultaneously by a wireless processing device of the wireless communication system, thereby producing an interference symbol pattern, the interference symbol pattern provides a non-zero probability of correctly decoding at least some of said group, and a substantially zero probability of erroneously decoding a canned message not in said group; detecting, by a portion of the plurality of wireless communication units, a triggering event that does not originate from, and is not controlled by, the wireless communication system; selecting, by each of said portion, one of the plurality of canned messages as a selected message to be transmitted in response to the triggering event; and transmitting, by each of said portion, one of the plurality of orthogonal codes corresponding to the selected message during a randomly-selected slotted-aloha time slot.