Introduction The need for highly efficient, linear microwave power amplifiers has grown rapidly, especially as mobile and satellite communication systems have been developed and expanded [1]. These systems employ multilevel digital modulation techniques to achieve higher-data-rate and multimedia services. This results in a band-limited multi-carrier signal, which is spectrally efficient but exh...

Wireless communication system are developing rapidly, due to which new standards like WIMAX and 4G Long Term Evaluating(LTE) with a purpose of achieving high data rate result in high end applications such as high speed internet, video conferences and broadband width. These applications require mobile base stations at the transmitter as well as at receiver (T/R) to support features like multiple...

A broadband power amplifier designed and implemented in Doherty configuration is illustrated in this paper. Both input and output networks adopt the broadband matching topology. Additionally a compensation network, consisting of a series transmission line shunted with a capacitance, is set behind the peak amplifier to avoid in-band power leakage in the low-power section while at the cost of pea...

In modern wireless communication systems it is required that the power amplifier could operate with high efficiency, high linearity, and low harmonic output level simultaneously. To increase efficiency of the power amplifier, a switching-mode Class E mode technique can be applied. This kind of a power amplifier requires an operation in saturation mode resulting in a poor linearity, and therefor...

The load networks of advanced Doherty power amplifiers (DPAs) have traditionally been designed according to the ABCD parameters. In this paper, design conditions as an impedance transformation condition and effective electrical length were used output matching (OMNs) for carrier peaking virtual-stub DPAs (VS-DPAs). An optimization method was proposed that specifically constructed impedances amp...

RF power amplifiers in mobile WiMAX transceivers operate in an inherently nonlinear manner. It is possible to amplify the signal in the linear region, and avoid distortion, using output power back-off; however, this approach may suffer significant reduction in efficiency and power output. This paper investigates the use of Doherty techniques instead of back-off, to simultaneously achieve good e...

Today’s wireless system requirements demand increasing performance from power amplifiers. The higher gain and output power available from today’s transistors reduce the number of amplifier stages, and improved efficiency decreases system DC power requirements and generated heat. But at these higher power and efficiency levels, power amplifier linearity needs to meet or exceed the requirements o...