| 摘要 |
PROBLEM TO BE SOLVED: To relax the demand that is given to the output linearity of an HPA which is an amplifier and to transmit the data signals at a high speed and with high efficiency by transmitting the data signals, after modulating the diffu sion of these signals via a diffusion code series and in a binary series state. SOLUTION: An adaptive modulation part 4 selects a Walsh function series according to a control signal and in response to a case that the data transmission rate shows each transmission rate of those data which exceed 512 kbps. Then a Walsh function having polarity is selected, in response to the inputted coding data and outputted, as a biorthogonal signal. A QPSK spreader 5 uses biorthogonal signals of two systems having plural pieces of coding data information which are outputted from the part 4 as its input and performs the QPSK diffusion modulation by means of a long code. The signals, which are subjected to QPSK diffusion modulation via the spreader 5 undergo the QPSK carrier modulation by means of an orthogonal carrier wave, are amplified by an amplifier 6 and transmitted to the outside via an antenna 7. |
