Highly Efficient Balanced Power Amplifiers for 4G Applications

This paper presents a highly efficient balanced power amplifier for 4G applications using a microstrip branch line coupler. A compact U-shaped microstrip branch line coupler is used for the balanced power amplifier (PA) architecture. The balanced PA achieves a power aided efficiency (PAE) of 66.8% what makes it very applicable for the 4G and 5G communication systems. The simulated and measured S-parameters (S_11 and S_22), gain, output power and power spectra densities for 3 MHz LTE signals at 1.5 GHz are presented.