Optimization design of fragment-type filtering matching network for continuous inverse class-F power amplifier

Abstract

This paper proposes a filtering matching network optimization design method using the fragment-type structure for continuous inverse class-F (CCF^-1) power amplifier (PA). Different from the conventional microstrip matching structure, the fragment-type structure is used to increase the flexibility of optimization for a sharp roll-off at the second harmonic band. By using a multi-objective evolutionary algorithm, a filtering output matching network (OMN) with the fast transition between the passband and stopband is designed and optimized. For verification, a 1.5-3 GHz broadband CCF^-1 PA is designed, simulated and measured. Simulated results show that, compared with conventional Chebyshev filtering OMN design, the operational bandwidth of the proposed design can be expanded by about 15%. Experimental results show that measured efficiency of 65%-77% with a corresponding output power of 40.2-42.2 dBm over a fractional bandwidth of 66.7% can be achieved.