| 摘要 |
Provided is a demodulation device which can surely perform demodulation even in a communication environment where the modulation index changes. Upon reception of communication signals of different modulation indexes from other ships, the demodulation device (1) performs detection/demodulation by using both of synchronous detection and frequency detection. The detection/demodulation result is judged to be correct or incorrect according to an error detection code and the demodulation data judged to be correct is outputted. That is, if both of the detection results are judged to be correct, the demodulation device (1) outputs one of the demodulation data, for example, the synchronous detection/demodulation data. On the other hand, if only the synchronous detection/demodulation data is judged to be correct, the demodulation device (1) outputs synchronous detection/demodulation data S. If only the frequency detection/demodulation data is judged to be correct, the demodulation device (1) outputs the frequency detection/demodulation data F. |
