The mobile phone signal amplifier is a repeater system, mainly an optical fiber repeater, and some small places temporarily use a wireless repeater to make up for the problem of weak signal coverage.
Basic principle: the main antenna sends the received downlink signal of the base station to the duplexer, and the duplexer filters the signal and sends the uplink signal to the low noise amplifier for first-stage amplification. The amplified signal contains spurious signals. The signal must be filtered again. In order not to affect the working efficiency of the subsequent stage and to have a good suppression of other signals, a filter with a good waveform moment must be selected to meet the requirements. In such a high frequency, it is generally common The filter can't meet the requirements, we use the intermediate frequency band selector to filter at the intermediate frequency to meet the requirements.
By adjusting the center operating frequency of the filter, the entire operating frequency band can be moved up or down, which can be adjusted flexibly according to the actual situation on site. The filtered signal is sent to a high-power amplifier for amplification, and finally the signal is filtered again by a duplexer and then transmitted from the retransmission antenna to cover the area to be covered. In this way, there is a signal where the signal is weak or there is no signal.
