Linearization technique for reducing third- and fifth-order intermodulation distortion products in multichannel amplifiers

A linearization technique that uses the injection of the fundamental signal second harmonics together with the fundamental signals at the amplifier input has been extended in this paper by introducing the injection of fourth-order nonlinearity of the fundamental signals in order to reduce fifth-order intermodulation products. Besides the improvement in third- and fifth-order intermodulation power levels achieved by applying the linearization technique proposed in this paper considerably better improvement is attained for the power of fundamental signals close to 1-dB compression point in comparison to the linearization with the injection of mere second harmonics.