Impedance Analysis of Mobile Phone Antenna in the Presence of User's Hand

Abstract

User interaction (UI) has been identified to degrade the performance of the antenna. A system that measures impedance characteristics of a planar inverted-F antenna (PIFA) when there are user interactions is designed using Keysight VEE Pro. The operational frequencies of the antenna are 900 MHz and 1800 MHz at low band and high band, respectively. The obtained results are compared and then a new impedance matching circuit is proposed and designed by using ADS (Advanced Design System). The proposed matching circuit at each operating frequency is a basic lumped circuit using the L network. Both simulation and experimental work have been done.