| 摘要 |
PURPOSE: To simplify constitution and to reduce cost by using circuits in a transmitting part and a receiving part in common and to prevent the generation of interference at the time of applying an SS type radio equipment to a weak radio wave type half-duplex radio equipment. CONSTITUTION: Base band transmitting information is modulated by a primary modulation circuit 18, an information-modulated wave with intermediate frequency is converted into a high frequency wave by a double balanced mixer 11 and a local oscillator 13 and the high frequency information-modulated wave is diffusely modulated by a double balanced mixer 7 and a diffusing code generator 10. A received signal at high frequencies and a wide band is demodulated by reverse diffusion through the mixer 7 and the generator 10, an information- modulated wave with high frequency and a narrow band is converted into an intermediate frequency wave through the mixer 11 and the oscillator 13 and the information-modulated wave with the intermediate frequency is demodulated by a primary demodulation circuit 17. In the transmitting modulation part and the receiving modulation part, only the primary information modulation and demodulation circuit 18, 17, IF amplifiers 15, 16, a transmitting amplifier 5, and a receiving amplifier 4 are independently prepared. |
