| 摘要 |
PURPOSE: To obtain a spread code having an accurate phase and code string for inverse spread in the receiver. CONSTITUTION: A delay detector 2 regenerated a spread code S2 from a signal S1 subject to spread spectral processing. A digital correlation device 4 executes the collation for each bit of the regenerated spread code S2 with each bit of a reference spread code S3 to calculate the correlation of the two codes. When an autocorrelation value exceeds a prescribed threshold level, it means that the recovered spread code and the reference spread code are made coincident. The phase of the regenerated spread code, and then the phase of a reception signal subject to spread spectrum processing is discriminated based on the timing. A multiplier 8 receives the reception signal subjected to spread spectral processing and a spread code S5 having the same code sequence as that of the reference spread code S3 outputted from a spread code generator 6 in phase synchronization, applies multiplication for each bit and outputs the modulation signal before spread processing by applying inversel spreading. |
