A LTE Doherty power amplifier using Envelope tracking technique

Along with the development of Long term evolution (LTE) communication system, higher linearity and efficiency of base station power amplifier required. Although, Conventional Doherty amplifier base station can´t meet this requirement. For the first time, This is the first use of Envelope tracking (ET) technology is used to dynamically control the gate voltage of Doherty power amplifier peak amplifier: at low power input, low voltage is supplied to the peaking amplifier, aiming to improve efficiency: on the other hand, at high power input, high voltage is supplied to the peaking amplifier to obtain high efficiency. Compared with the traditional power amplifier, the new design could improve the linearity without decreasing efficiency. In this paper, the design and simulation is conducted by Rogers 4350, and the third-order inter-modulation distortion (IMD3) is improved by 5-dBc with remaining the high efficiency. Physical test and simulation results are in good agreement with this article´s index.