| 摘要 |
PURPOSE:To form a diversity receiver with high diversity effect by varying a switching threshold value in matching with the fluctuation of a received electric field. CONSTITUTION:When the power of a reception signal is obtained by a power detection circuit 20, it is compared with a switching threshold value stored in a memory 50 by a comparator 30 being the 1st comparator, and when the reception signal power is smaller then the switching threshold value, the comparator 30 outputs a switching signal. A noise level obtained by a power detection circuit 20 is inputted to a noise integration circuit 40 at the same time, and the noise integration circuit 40 integrates it and when the quantity of integration reaches a prescribed value, a switching signal is outputted. When a switching signal is outputted from the comparator 30 or the noise integration circuit 40, an OR circuit 60 outputs the switching signal to allow an antenna switching circuit 10 to switch an antenna and the reception power at that time is written in the memory 50 to reset the content of the circuit 40.
|
