Patent ID: 7379717
Filing Date: 2008-05-27
Classification: H04B

Abstract:
1. An apparatus comprising: a bi-directional RF amplifier connected by a first coaxial cable to a transmit/receive antenna and connected by a second coaxial cable to a network access point, the amplifier having a data input port and a data output port, and the access point having a data input port; a first data cable capable of carrying power, one end of such first data cable connected to the output port of the RF amplifier and the other end connected to the input port of the access point; a second data cable capable of carrying power having one end connected to the input port of the amplifier and the other end connected to a power injector for providing power to the amplifier; a third data cable for connecting the power injector to a data network; and a power source for delivering power to the power injector; wherein the amplifier further comprises: a directional coupler connected to the second coaxial cable, and to a power detector that detects the presence of an RF signal, and to a first RF switch; a microcontroller connected to the power detector that reads the presence of an RF transmit signal from the power detector and sends a control signal to the first RF switch and to a second RF switch, both RF switches being set to a transmit mode if an RF transmit signal is present and being set to a receive mode if an RF transmit signal is not present; an attenuator connected to the first RF switch and to the microcontroller, and also to at least one fixed-gain RF amplifier stage, so that when the microcontroller sends a predetermined control signal to the attenuator, the attenuator sets the level of the RF transmit signal to not saturate the input of the fixed-gain RF amplifier stage to which it is connected; the second RF switch being connected to the output of the fixed-gain RF amplifier stage to receive an amplified RF signal from the fixed gain RF amplifier stage and routing the signal over the first coaxial cable to the transmit/receive antenna for RF transmission when the microcontroller has set the first RF switch and the second RF switch to transmit mode; a bandpass filter connected to a low noise amplifier and to the second RF switch so that when the microcontroller has set the first RF switch and the second RF switch to receive mode, the second RF switch routes any signal present on the antenna to the bandpass filter, the bandpass filter set to block any signal outside a predetermined radio frequency band and to pass the filtered signal to the low noise amplifier; the low noise amplifier being further connected to the first RF switch to allow the first RF switch to route any amplified signal from the low noise amplifier through the directional coupler and from there to the second coaxial cable.