| Patent application number | Description | Published |
|---|
| 20100074240 | Duplexer/Multiplexer Having Filters that Include at Least One Band Reject Filter - A wireless communications device includes an antenna, a multi-port path selection structure having an antenna port connected to the antenna, and plural ports connected to respective one or more receive and transmit paths of the wireless communications device. The multi-port path selection structure has a transmit band reject filter connected to the transmit path and a second filter connected to the receive path. | 03-25-2010 |
| 20100265010 | DEVICE AND METHOD FOR CASCADING FILTERS OF DIFFERENT MATERIALS - Some embodiments of the invention provide a filter having at least one first filter, each first filter being a band-reject type filter having a first set of filter parameters that are a function of a first material used to fabricate the at least one first filter, and at least one second filter, each second filter having a second set of filter parameters that are a function of a second material used to fabricate the at least one second filter, each second filter being one of a band-reject type filter and a band pass type filter. The at least one first filter and the at least one second filter are then cascaded together to form the filter. The first material and the second material are different materials. The cascaded filter has a new third set of filter parameters that are a function of both the first material and the second material. Other embodiments of the invention include a method for fabricating the filter and a method of filtering using such a cascaded filter. | 10-21-2010 |
| 20100308911 | BAND REJECT FILTERS - Distributed band reject filters are disclosed. A band reject filter includes a first acoustic resonator and a second acoustic resonator, each of which has either shunt resonators adapted to resonate substantially at respective resonance frequencies defining a rejection frequency band or series resonators adapted to anti-resonate substantially at respective anti-resonance frequencies defining the rejection frequency band. These resonators are connected through a phase shifter which imparts an impedance phase shift of approximately 45° to 135°. Exemplary applications of the band reject filters disclosed herein include implementation as an inter-stage band reject filter for a base station power amplifier for a wireless communication system, as a radio frequency band reject filter in a duplexer for a wireless communication terminal, and in a low noise amplifier input stage. | 12-09-2010 |
| 20110109403 | FILTER HAVING IMPEDANCE MATCHING CIRCUITS - A filter package is provided with a support structure, a filter device having terminals, impedance matching circuits formed on the support structure and electrically connected to at least some of the terminals of the filter device, and at least one electrical ground structure electrically connected to the impedance matching circuits. Moreover, the filter package has an outer housing to contain the support structure, filter device, impedance matching circuits, and at least one ground structure. | 05-12-2011 |
| 20110235557 | SELF-MATCHED BAND REJECT FILTER - The present application describes a radio frequency band reject filter including an input port, an output port, a plurality of acoustic resonators and an inductor for matching the impedance of the plurality of acoustic resonators. The inductor is positioned within the band reject filter in respect of the plurality of acoustic resonators such that a static capacitance between the input port and the inductor is substantially equivalent to a static capacitance between the output port and the inductor. The plurality of acoustic resonators may be a plurality of parallel resonators, a plurality of series resonators or a combination of series and parallel resonators. The radio frequency band reject filter is fabricated using any of surface acoustic wave (SAW) technology, thin film bulk acoustic resonator (FBAR) technology, and bulk acoustic wave (BAW) technology. | 09-29-2011 |
| 20110248795 | BAND REJECT FILTERS - Distributed band reject filters are disclosed. A band reject filter includes a first acoustic resonator and a second acoustic resonator, each of which has either shunt resonators adapted to resonate substantially at respective resonance frequencies defining a rejection frequency band or series resonators adapted to anti-resonate substantially at respective anti-resonance frequencies defining the rejection frequency band. These resonators are connected through a phase shifter which imparts an impedance phase shift of approximately 45° to 135°. Exemplary applications of the band reject filters disclosed herein include implementation as an inter-stage band reject filter for a base station power amplifier for a wireless communication system, as a radio frequency band reject filter in a duplexer for a wireless communication terminal, and in a low noise amplifier input stage. | 10-13-2011 |
