| 摘要 |
PURPOSE:To retrieve the best point with high accuracy at all times even when the frequency of a disturbing wave is fluctuated by providing functions of coarse adjustment and fine adjustment respectively to both a variable amplitude adjusting device and a variable phase shifter separately. CONSTITUTION:The best point retrieval system consists of the 1st system comprising a variable phase shifter 12, a variable ATT1, a synthesizer 5 and a noise detector 6 and the 2nd system comprising a variable phase shifter 12, a variable ATT11, a synthesizer 15 and a noise detector 16. In the 1st system, the range of change of the variable phase shifter 12 is taken as 0-360 deg. and that of the variable ATT11 is taken as 0-30dB largely so as to retrieve always. In the 2nd system, the range of change is taken narrower such as + or -8 deg. for the variable phase shifter 2 and + or -2dB for the variable ATT1 near the best point of the variable phase shifter and variable ATT retrieved by the 1st system to increase the accuracy of the best point retrieval. the range of change is narrowed in this way so as to form the state that two disturbing waves are nearly completely canceled in the synthesizer 5. |
