Patent ID: 8143951

Claim:
A broadband multiple frequency RF amplifier configured to amplify multiple frequency RF input signals over an operating bandwidth to drive a load, the amplifier comprising: a transistor configured to amplify the RF input signals to drive the load; a power supply configured to provide power usable by said transistor to amplify the RF input signals; a bias filter, connected to said transistor and to said power supply, which is configured to couple the power supply to the transistor to supply DC energy from the power supply to the transistor, and which is further configured to block the amplified RF input signals over substantially the entire operating bandwidth from reaching the power supply; and a matching circuit configured to couple the transistor to the load, wherein a first impedance, seen by the matching circuit from the load, is substantially equal to a conjugate of the impedance of the load; wherein a second impedance, seen looking into the matching circuit from the transistor, is a conjugate of an operating impedance of the transistor; wherein a load impedance, seen by the bias filter, is substantially equal to the operating impedance of the transistor, and wherein a termination impedance of said bias filter on the power supply connection is one of a short circuit and an open circuit.