| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an optical transmitter which does not need a complex demodulation circuit for a radio subscriber terminal even when transmitting a wideband digital signal, in an optical-radio fusion communications system. <P>SOLUTION: In a first and a second electric oscillators which generate an electrical carrier signal, with which a sum of each center frequency is equal to the frequency of a desired radio signal, and the difference of each center frequency is equal to the frequency of the desired intermediate frequency signal, It phase-modulates the electrical carrier signal from one electric oscillator 4 with an input electric digital signal of binary (0, 1) by an electric phase modulator 6. Here, phase modulation, is applied so that the difference between the phase of an electric phase modulation signal to an electrical digital signal (0), and the phase of the electrical phase modulation signal with respect to an electrical digital signal (1) becomes π. Light modulation is applied to the output light from a single spectral optical source 3 by a light modulator 8, utilizing the electrical carrier signal from another electric oscillator 5 and an electric band signal acquired combining by an electric combining frequency machine 7. <P>COPYRIGHT: (C)2007,JPO&INPIT |
