| 摘要 |
PROBLEM TO BE SOLVED: To improve the communication quality of transmission through pluralities of channels where data different in quality, transmission rate and transmission delay coexist. SOLUTION: One symbol of low speed data is divided and assigned to a Ch1- a(b), Ch21- a(b), and Ch3- a(b) and high speed data are assigned to Ch1- c, Ch2- c, and Ch3- c and QPSK modulation to change adaptively signal point arrangement of the latter by controlling a data period of the former is applied to each code channel. Furthermore, when there are data to be sent, a proper data rate is set depending on a state of communication channels and quality required for each of data in parallel and phase shift keying such as BPSK or QPSK is applied to the data and the result is assigned to a Ch- 4. Then all code channels are multiplexed and the multiplexed channels are transmitted. |
