CARRIER TRANSMITTER AND RECEIVER

PROBLEM TO BE SOLVED: To suppress mixing of a signal with simple circuit constitution. SOLUTION: The radio transmitter and receiver having a transmitting circuit 1 which converts the frequency of a signal having its band spread with a dummy noise signal with the output of a high-frequency oscillator 14 and transmits it and a receiving circuit 2 which inputs a receive signal based upon the transmit signal, converts the frequency of the received signal with the output of the high-frequency oscillator 14, and detects the correlation with the dummy noise signal uses two higher-harmonic mixers 23 and 24 which converts the frequencies of input signals with higher harmonics of the output of the high-frequency oscillator and suppress the detour of the frequency-converted transmit signal to the reception side as the transmitting circuit 1 and receiving circuit 2, thereby suppressing the mixing signal by setting the frequency of the mixing signal to a multiple of the output frequency of the high-frequency oscillator 4.