Title:
TRAPEZOIDAL BROADBAND PIEZOELECTRIC FILTER
Document Type and Number:
WIPO Patent Application WO/2017/219251
Kind Code:
A1
Abstract:
A trapezoidal broadband piezoelectric filter, consisting of a series of first resonators connected in series, a series of second resonators connected in parallel, an impedance matching device located near an input end or an output end of the filter, and at least one specific parallel grounded circuit leaded out by a serial node. The specific parallel grounded circuit at least comprises an inductor of relatively high inductance, and a resonator having the same resonant frequency as that of a certain serial branch or a capacitor, the inductor of relatively high inductance being connected in series to the resonator or the capacitor in the parallel circuit. The trapezoidal filter can achieve a bandwidth two times or above than that of the traditional trapezoidal filter, and also has an excellent out-of-band rejection characteristic.
Inventors:
PANG WEI (CN)
ZHENG YUNZHUO (CN)
ZHENG YUNZHUO (CN)
Application Number:
PCT/CN2016/086596
Publication Date:
December 28, 2017
Filing Date:
June 21, 2016
Export Citation:
Assignee:
ROFS MICROSYSTEM(TIANJIN) CO LTD (CN)
International Classes:
H03H9/46
Foreign References:
| CN102055430A | 2011-05-11 | |||
| CN1507152A | 2004-06-23 | |||
| CN1518219A | 2004-08-04 | |||
| CN101277098A | 2008-10-01 | |||
| CN1619958A | 2005-05-25 |
Other References:
HASSAN, M, RECONFIGURATION OF BULK ACOUSTIC WAVE FILTERS: APPLICATION TO WLAN 802. 1 1B/G (2. 40-2. 48GHZ, 31 December 2006 (2006-12-31), XP031111509
Attorney, Agent or Firm:
DEHENG IP LAW, LLC (CN)
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