| 摘要 |
PURPOSE:To eliminate the necessity of separately installing a controlling circuit and to constitute a cheap circuit with high frequency utilization efficiency by inserting switching data into data in the transmitting side and sending the result to receiving side as a part of the data. CONSTITUTION:When change occurred in the form of terminal data, an N-M phase switching command signal (a) is inputted in a form shown in II. On receiving this N-M phase switching indication signal (a), a fixed code word generating circuit 21 generates a fixed code word (c) corresponding to the signal (a) and having a fixed pattern. The generated fixed code word (c) is inserted in an input data (b) by a signal composing circuit 22, and inputted to an N-M phase modulator 23 as a modulation data (d) in which a fixed code word is inserted in the middle. On the other hand, an inputted N-M phase switching command signal (a) is delayed by the length of the signal (a) in a signal delay circuit 24, and inputted to the modulator 23 as a delayed switching command signal (e). |
