Patent ID: 8190099

Claim:
A bi-directional amplifier for amplification of signals received or signals to be transmitted in a communication circuit, comprising: at least one first biased semiconductor amplification element coupled to a first impedance matching network; at least one second biased semiconductor amplification element coupled to a second impedance matching network; a first device for biasing said at least one first biased semiconductor amplification element and a second device for biasing said at least one second biased semiconductor amplification element wherein the direction of signal amplification in said bi-directional amplifier is controlled by said first or said second device for biasing said at least one first or second biased semiconductor amplification element; said first impedance matching network is a first common impedance matching network for said at least one first biased semiconductor amplification element and for said at least one second biased semiconductor amplification element; said second impedance matching network is a second common impedance matching network for said at least one first biased semiconductor element, wherein the first common impedance network is an output impedance matching network for said at least one first biased semiconductor element and an input impedance matching network for said at least one second biased semiconductor element, and the second common impedance matching network is an output impedance matching network for said at least one second biased semiconductor element and an input impedance matching network for said at least one first biased semiconductor element, the bi-directional amplifier further comprises means for achieving equal impedances for said at least one first and said at least one second biased semiconductor elements, wherein said means is connected between said at least one first and said at least one second biased semiconductor elements.