Automatic tunable antenna controlling varactors based on the received power of a probe

摘要: Built-in antennas in mobile equipments are often subject to changes input impedance due the proximity of objects, e.g. a user's hand/head, desk, etc. The resulting mismatch can lower efficiency RF power amplifiers (PAs), will reduce battery life, cause low communications quality, To mitigate these problems, novel automatic tunable antenna system using probe is proposed this paper. controls two varactor diodes (VDs) matching circuit (MC) according received probe. When less than -20dB relative MC for all VD conditions, corresponds only -0.01dB loss which considerably insertion directional coupler. Moreover, frequency independent, consequently significantly wideband, and operate from 700MHz 2.7GHz. A prototype programmable logic device (PLD) also demonstrated.