| 摘要 |
PURPOSE:To make it possible to obtain accurate data by receiving the data from a ground apparatus, storing the demodulated signals back to the past, adding the signals for every same bit, and performing majority judgment for the obtained values for every bit. CONSTITUTION:A received signal Sa is demodulated in a Differential-Phase-Shift Keying (DPSK) demodulating circuit A, and a demodulated signal Sb is led out. The signal is supplied into a Barker-code detecting circuit B and a shift register/latch circuit D. In the circuit D, shifting of the signal Sb is performed in response to a sampling pulse Sd, and latching of the signal Sb is performed in response to a sampling pulse Se. Then, the demodulated signal Sf is stored in a synchronous adding means E. The signals are added for every same bit for the specified period in the past. The added result Sg is supplied into a majority judging means F. Then, majority judgment is performed in the means F, and the demodulated data Sh are outputted. In this way, the data error rate is decreased by performing the majority judgment, and the basic data and the auxiliary data having the high accuracy are obtained in the wider region. |
