| 摘要 |
PURPOSE:To acquire synchronism in a short time and to easily judge the coincidence of codes by synchronizing the phases of codes while utilizing correlation output time difference caused by a surface acoustic wave (SAW) device correlation equipment. CONSTITUTION:A code generating circuit 3 generates a code sequence F at the same speed as under a code sequence used for the diffusion of spectrum on the transmission side. A carrier reproducing circuit 4 performs transmitting carrier reproducing from a received signal to a BPS similarly to synchronizing detection. A first balanced modulation circuit 5 performs the spectrum diffusion by adding the phase modulation to the reproduced carrier with the code sequence generated by the circuit 3. The received diffused spectrum signal is inputted to a first SAW matched filter 1, and the output of the circuit 5 is impressed to a second SAW matched filter 2. The respective filters 1 and 2 output correlation output pulses corresponding to the timing of the inputted code sequence F respectively. A pulse position comparator circuit 8 compares the time intervals of pulses from the filters 1 and 2, and a clock control circuit 9 controls a clock in a certain direction so that the time difference is turned to '0'. |
