| 摘要 |
PURPOSE:To improve a signal-to-noise ratio without changing a process gain by close arranging plural primary modulated wave signals in a condition in which they are not interfered and executing a spectral spreading by a single spreading code. CONSTITUTION:Plural primary modulated wave signals are prepared to a piece of information data, respective primary modulated wave signals are close arranged in maintaining the condition in which they do not interfere with one another, and by executing a spreading by a spreading code to consider a clock signal frequency for the spreading code set beforehand and the period of the spreading code, the spectral spreading without a spectral interference is executed. Further, at the time of demodulating, the detection of plural modulated wave signals, after a reverse spreading, is executed. Thus, the S/N of the information data obtained by being detected can be improved in proportion to plural primary modulated wave signals, and when an S/N improvement degree is equal, a spectrally spread band width can be made narrow by the degree. |
