| 摘要 |
PROBLEM TO BE SOLVED: To transmit a wide band sound signal by transmitting a spectrum envelope information parameter and a sound source information parameter to a first frequency band signal and transmitting only the spectrum envelope information parameter to a second frequency band signal. SOLUTION: A transmission orthogonal mirror filter 60 divides an input sound signal a4 into a low band component c4 and a high band component b4. The component c4 is encoding-processed by a highly efficient sound encoder 62 and a sound information parameter e4 is outputted. On the other hand, the component b4 is processed by a linear analyzer 61 and a linear prediction coefficient d4 for representing spectrum envelope is outputted. The coefficient d4 from the analyzer 61 and the parameter e4 from the encoder 62 are encoded and are made into frames by an encoder 63. Then, a data string f4 being the result is transmitted to a transmission line. Thus, the wide band sound signal can be encoded and transmitted as well in mobile communication taken place by using a radio line limited in information transmission speed. |
