| 摘要 |
A filter arrangement for use in a multiband dual-mode mobile phone. In particular, the mobile phone is operable in a W-CDMA mode and a band-reject filter comprising at least a series and a shunt acoustic-wave resonators is used to create a deep notch at the receive frequency band. The band-reject filter further includes a plurality of inductive elements for matching static capacitance of the resonators at the passband frequency. The mobile phone is also operable in 1800 and 1900 GSM bands. The band-reject filter is operatively connected to a harmonic trap in order to eliminate the third harmonic of these GSM bands. The mobile phone is also operable in the lower GSM band, for which a harmonic filter can share an antenna path with the band-reject filter.
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