| 摘要 |
<p>PURPOSE:To make easy the synchronism at the reception side, by optimizing the coding of information so that the maximum phase shift angle can be obtained in advance when polyphase differential phase modulation is made. CONSTITUTION:The control circuit 1 discriminates the input information whether the control instruction signal A or B, and according to the result of discrimination, the selection signal 1a and either of readout signal 1b or 1c are outputted. The selection circuit 2 selects either one of the data 3a or 4a outputted respectively from the pattern generator, e.g., read only memories 3 and 4, according to the selection signal 1a, and outputs it as the signal 2a, and it consists of gates. In the memory 3, as the bit pattern, 111000111000 representing the control instruction signal A is stored, and 111111000000 representing the control instruction signal B is stored in the memory 4. The signal 2a is fed to the polyphase differential phase modulator for phase shift modulation in response to dibit unit.</p> |
