| 摘要 |
PROBLEM TO BE SOLVED: To reproduce correctly a reference carrier signal in inverse modulation. SOLUTION: In the biphase modulation transmitter-receiver that sends/receives information data, a transmitter 10 shifts pseudo noise data for a prescribed period by 90 deg. with respect to biphase-modulated information data and synthesizes the shifted data with the information and transmits the resulting data. A receiver 20 applies inverse-modulation to a modulation signal obtained by applying synchronization detection to the received signal to generate a reference carrier signal. A pseudo noise generator 25 generates the same data as pseudo noise data in the transmitter with a prescribed phase shift and uses the pseudo noise data with the confirmed phase to apply inverse-modulation to the reception signal so as to generate the reference carrier signal. A correlation device 24 checks the correlation between the pseudo noise data with a prescribed amount of phase shift from the pseudo noise generator and the pseudo noise data obtained through synchronization detection and discriminates that the phase of the pseudo noise data of the pseudo noise generator is confirmed when the correlation is higher than a prescribed value or over. |
