| 摘要 |
A spread spectrum digital communication method by Golay complementary sequence modulation is provided to be capable of improving quality by using spread spectrum technology and CDMA(Code Division Multiple Access) properties, while a transmission gain independent of transmission speed can be obtained. A communication system consists of a transmitter device and a receiver device. The transmitter device comprises the followings. A receiver(a.1) is equipped. An encoder(a.2) encodes received NRZ(Non-Return-to-Zero) digital data, and forms groups. A Golay register(a.3) consists of two binary registers of M length. A multiplier(a.4) consists of two multipliers and one symbol. A double accumulator/shift register(a.5.6) consists of a double accumulator for executing arithmetic addition of results of the multiplier(a.4), and a shift register for evaluating the results. An adder(a.7) independently adds data corresponding to output of each register. A QPSK(Quadrature Phase Shift Keying) modulator(a.8) modulates output signals of the adder(a.7), and derives a transmission signal and a QPSK signal. An output stage(a.9) consists of a D/A(Digital to Analog) converter stage and an existing RF(Radio Frequency) stage. |
