IMPROVEMENTS IN OR RELATING TO PORTABLE WIRELESS DEVICES

摘要

A method of offsetting a mismatch due user interaction when handling a portable wireless terminal in which antenna matching is changed from inductive matching to capacitive matching in response to a reactance change exceeding a threshold level and vice versa when an opposite change is detected. An antenna interface module (44) is coupled between a RF output or input stage (25 or 33) and an antenna (48 or 50). The antenna interface module includes first and second switches (SW1/1, SW1/2 or SW2/1, SW2/2), a first matching circuit including an inductive reactance (68 or 96) coupled between the power amplifier and the first switch and a second matching circuit including a capacitive reactance (68 or 92) is coupled between the RF output or input stage and the second switch (SW1/1 or SW2/1). A reactance threshold detector (54 or 56) determines if the reactance change traverses a predetermined threshold value and causes the first and second switches to be actuated so that the matching changes from inductive to capacitive or vice versa.