| 摘要 |
In a wireless communications system, an RF booster provided intermediate an antenna device for receiving RF signals and a receiver device for providing a predetermined amount of gain to said received RF signals and converting said RF signals to audio frequency signals, the RF booster comprising a first amplifier device for receiving input signals from the antenna via a first cable connecting device, the first low noise amplifier providing a first gain equal to the predetermined amount of gain of the receiver device; a second amplifier device connected in series with the first amplifier device, the second amplifier device connected via a second cable connecting device to the receiver device and providing a second amount of gain of a value sufficient to compensate for signal loss provided by the first and second cable means; and a switch element capable of switching out the first gain of the first amplifier device, the switch element controlled by a control signal in accordance with a sensed level of received input RF signals, wherein for small input RF signals received, the switch element is switched off to provide both the first and second gain in the RF booster, and for large input signals received, the switch element is switched on to provide only the second gain for the RF booster.
|
