| 摘要 |
A simplified process of signal detection in a multiple access data communications uses a small number of different spreading signals rather than a single spreading signal such as used in a Spread ALOHA multiple access network. The process selects a spreading signal which depends upon a property of the signal being transmitted rather than upon the transmitter which is transmitting the signal as in Code Division Multiple Access (CDMA). Multiple transmitters can use pilot signals and transmit the multiple data signal with the selected spreading sequences. The hub station receives the multiple data signals and detects the multiple data signals with matched filters or correlators matched to the code spreading sequences. Outputs of the matched filters or correlators can create control signals for offsetting the transmitted data signals by advancing or retarding timing of the transmitting of the multiple data signals from the multiple transmitters. The spreading signal for each transmitter may also depend upon whether the transmission is on the "in phase" channel or the "quadrature" channel, thus doubling the number of spreading codes used in the data network. The codes selected for spreading in such a dual code (or multiple code) Spread ALOHA network can be different "m-sequences" for each class of traffic.
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