Abstract:In order to satisfy the requirements of smart antenna beamforming, an adjustable powersplitter and phaseshifter microstrip circuit has been developed for radiation pattern measurement of smart antenna in microwave anechoic. The circuit is composed of Wilkinson power divider, πtype resistance attenuator, loaded line phase shifter and cascade of a coaxial transmission line. The onetofour powerdivider and phaseshifter microstrip circuit has been realized with power ratio 1∶2∶2∶1 and sequence phase difference 105 degrees in TDLTE F band. Simulation software of HFSS was used to optimize the design of the circuit. And the circuit was fabricated and measured. The measured results show that the input VSWR is less than 1.2 with the amplitude error less than 0.5 dB and the phase error less than 3°. The structure of the circuit is of low cost, and the distribution of the amplitude and phase is easy to adjust. It can meet the needs of the testing application.