HARMONIC SUPPRESSION IN DUAL BAND MOBILE PHONES

摘要

To effectively suppress harmonics in a dual band mobile phone with a power amplifier (10) outputting transmitting signals for different frequency bands (GSM; PCS, DCS) via a single output as described a power amplifier output circuit in which harmonics are filtered through impedance transformation of a turn-off impedance of a transmitter/receiver change over unit (36, 38). Hereby the desired filtering of harmonics may be achieved without almost no additional expenditure.