| 摘要 |
PROBLEM TO BE SOLVED: To efficiently transmit information, while being compressed by deleting information in the comparatively low degree of importance and while being modulated to reduce transmission error generation probability by transforming digital video information through discrete cosine transformation(DCT) and modulating that information, while using 4-phase shift keying when transmitting it through radio waves. SOLUTION: A video signal and an audio signal are separately inputted to compression circuits 22 and 23, and the video signal are bit compressed by DCT. The output signals of the compression circuits 22 and 23 are inputted to a parity addition circuit 24, a parity signal is added for correcting an error to be generated during transmission and according to a transmission format, signal processing is performed such as serially outputting the video signal and the audio signal. The output signal of the parity addition circuit 24 is inputted to a modulation circuit 25. Corresponding to the characteristics or frequency band of a transmission line 27, the serial signal is modulated at the modulation circuit 25. In this case, the transmission line 27 is a space, and when transmitting the information through radio waves, for example, it is modulated at the modulation circuit 25 by 4-phase shift keying. |
