摘要:
A surface acoustic wave filter, has: a piezoelectric substrate; and at least two filter tracks having at least an input interdigital transducer electrode and an output interdigital transducer electrode provided on said piezoelectric substrate, wherein the respective input interdigital transducer electrodes of said at least two filter tracks are brought into connection in parallel; the respective output interdigital transducer electrodes of said at least two filter tracks are brought into connection in parallel, and overlapping widths of electrode fingers of said input interdigital transducer electrode and output interdigital transducer electrode are different from each other for each of said at least two filter tracks.
摘要:
A time division multiple access FDD wireless unit has a first local oscillator 8 for oscillating a first frequency; a second local oscillator 12 for oscillating a second frequency ; a n-time multiplier 14 for multiplying the second frequency by n; a m-times multiplier 18 for multiplying the second frequency by m; a converter 6 for transmitting frequency of difference between a reception signal and an output of the first local oscillator 8; a converter 11 for transmitting frequency of sum or difference between an output of the converter 6 and an output of the n-times multiplier 14; modulator 19 for modulating an output of the m-times multiplier 18; a converter 22 for transmitting frequency of sum of an output of the modulator 19 and the output of m-times multiplier 18.
摘要:
The present invention comprises baluns 2a, 2b which convert balanced line signals and unbalanced line signals mutually, and filters 3a, 3b which are electrically connected to the baluns 2a, 2b and pass or attenuate the predetermined frequency bands. Electrode layers 15a-22a, 25a, 41, 42, 43 which compose the electrode patterns of the baluns 2a, 2b and the filters 3a, 3b, and the dielectric layers 30-39 are integrally stacked.
摘要:
An inter-digital transducer has a piezoelectric substrate; and an IDT (inter-digital transducer) electrode having a pair of upper bus bar electrode and lower bus bar electrode placed facing each other on the piezoelectric substrate and a plurality of electrode fingers placed on the piezoelectric substrate each being led out from either the upper bus bar electrode or the lower bus bar electrode toward the other bus bar electrode, wherein the IDT electrode is constructed of a plurality of divisional IDT electrodes and connected to a balanced type terminal.
摘要:
A high-frequency filter device including at least one filter to be connected to a high-frequency stage of a wireless apparatus, in which the filter includes a voltage-controlled variable frequency resonance element which comprises a resonance element and a voltage-controlled variable impedance element electrically connected to the resonance element. The high-frequency filter device includes a control section for controlling a voltage applied to the variable impedance element, and a signal monitoring section for outputting a control signal, with which the voltage is controlled, to the control section based on frequency data as to an oscillating frequency of a local oscillator of the wireless apparatus, and the signal monitoring section controls a band frequency of the at least one filter based on the frequency data in such a manner that the band frequency is adaptively changed.
摘要:
A multilayered ceramic RF device having at least one radio frequency filter, includes: a low temperature-cofired multilayered ceramic body having a plurality of ceramic layers laminated one upon another and fired together, said low temperature-cofired multilayered ceramic body also having a first electrode pattern formed therein and a second electrode pattern formed thereon, the first and second electrode patterns being electrically connected to one another through a via hole; and a bare semiconductor chip mounted on said low temperature-cofired multilayered ceramic body with a face down bonding, said bare semiconductor chip being coated with a sealing resin. The at least one radio frequency filter is a multilayered filter formed in said low temperature-cofired multilayered ceramic body, and the multilayered filter includes a part of the first and second electrode patterns.
摘要:
An antenna duplexer has a transmission input terminal, a receiving output terminal, an antenna terminal in which a transmission output terminal and a receiving input terminal are used in common, a transmission filter having at least one resonance element set between the transmission input terminal and the transmission output terminal and coupled by a coupling element, a receiving filter having at least one resonance element set between the receiving output terminal and said receiving input terminal and coupled by a coupling element, and an impedance variable element connected to the resonance element of the transmission filter and the resonance element of said receiving filter respectively in parallel, wherein the frequency transfer characteristic of the transmission filter and the frequency transfer characteristic of the receiving filter are controlled by applying control signals and thereby changing the impedances of the impedance variable element.