| 摘要 |
PURPOSE:To make unnecessary the base band filter for AGC in the master station and to increase the reliability, by performing AGC with the use of the pilot signal for the slave station each channel, in multi-directional line network of SSB multiplex radio system. CONSTITUTION:The base band signal having different level every direction from each slave station and the pilot signal are branched at the hybrid 1 and fed to the pilot filter groups 3A to 3C and the carrier terminal unit 2. The pilot signal picked up every direction is fed to the AGC amplifiers 4A11 to 4A6, 4B1 to 4B6 and 4C1 to 4C6 corresponded and the audio signal and the linger tone each channel separated with the unit 2 are respectively fed to each amplifier 4. The variable gain amplifier 41 for AGC in each channel 4 synthesizes and amplifies each input signal, rectifies 44 the pilot signal, controlling the gain of the amplifier 41 with the rectified output. |
