| 摘要 |
When a multiplier receives data transmitted from a transmitting equipment in a spread spectrum communications system, it multiplies the received data by the periodic wave output from a crystal oscillator. The output data from the multiplier is filtered by a low-pass filter, and then binarized by a limiter. The multiplier and a delay circuit differential-decodes the binarized data. A correlation circuit obtains correlation between the decoded data and the PN code generated by the PN code generation circuit, and outputs the data as transfer data when the correlation is obtained. In another aspect, an input signal is divided, and then one is multiplied by an I-phase wave. Similarly, another is multiplied by a Q-phase wave. Each signal is individually processed and input to a correlation value/data value determination circuit. The correlation value/data value determination circuit compares an I-phase correlation value with a Q-phase correlation value, and obtains and outputs a data value of one of the phases whichever indicates a larger value. |
