摘要 |
A spread spectrum system includes a transmitter in which a frequency of a pseudonoise sequence signal is modulated in accordance with information, and a receiver in which a received pseudonoise sequence signal is demodulated based on a synchronization between the received pseudonoise sequence siganl and a reference pseudonoise sequence signal having the same basic frequency as the received pseudonoise sequence signal. An initial acquisition method used in the spread spectrum system includes the following steps (a) and (b) of: (a) transmitting a training signal from the transmitter, the training signal being obtained by changing the frequency of the transmitted pseudonoise sequence signal from the basic frequency before the frequency of the transmitted pseudonoise sequence signal is modulated; and (b) carrying out a sliding correlation in the receiver based on a difference between a frequency of the training signal and the basic frequency of the reference pseudonoise sequence signal, so that an initial acquisition is achieved by the sliding correlation.
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