With Specific Filter Structure Patents (Class 455/307)
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Patent number: 8670733Abstract: A multimode communication device with a shared signal path programmable filter and a method for utilizing a shared signal path programmable filter in a multimode communication device. Various aspects of the present invention comprise a first module adapted to receive a first communication signal (e.g., corresponding to a first communication protocol) and a second module adapted to receive a second communication signal (e.g., corresponding to a second communication protocol). A shared filter, communicatively coupled to the first and second modules, may be adapted to filter the first and/or second communication signals in accordance with a plurality of selectable sets of filter response characteristics (e.g., associated with the first and second communication protocols). A filter control module may be adapted to select a set of filter response characteristics from a plurality of such sets and program the shared filter to filter a communication signal in accordance with the selected set.Type: GrantFiled: January 23, 2012Date of Patent: March 11, 2014Assignee: Broadcom CorporationInventors: Arya Behzad, Ahmadreza Rofougaran
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Patent number: 8666350Abstract: A circuit includes, an attenuator responsive to an input signal and a feedback signal, a variable gain low-noise amplifier responsive to the attenuator and to the feedback signal, a tracking filter, a frequency converter, and an RSSI responsive to the variable gain amplifier to generate an output signal to which the feedback signal is responsive. The frequency converter may be a mixer having a single-ended input and a differential output. The circuit may further include an analog baseband block responsive to the mixer to filter out high frequency signals. The tracking tuner performs bandpass filtering operation on the output signals of the variable gain low-noise amplifier.Type: GrantFiled: November 24, 2010Date of Patent: March 4, 2014Assignee: MaxLinear, Inc.Inventor: Ari Vauhkonen
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Patent number: 8666351Abstract: A SAW-less receiver includes an FEM interface module, an RF to IF receiver section, and a receiver IF to baseband section. The RF to IF receiver section includes a frequency translated bandpass filter (FTBPF), an LNA, and a mixing section. The FTBPF includes a switching network and baseband impedances. The switching network is operable to frequency translate a baseband filter response to a first RF band frequency response and/or to a second RF frequency band response. The FTBPF filters the inbound RF signal to pass, substantially unattenuated, the first and/or second RF band signal components. The LNA amplifies the first and/or second filtered inbound RF signals and the mixing section mixes the first and/or second amplified inbound RF signals with a corresponding first and/or second local oscillation. The IF to baseband section converts the first and/or second inbound IF signals into first inbound symbol stream(s) and/or second inbound symbol stream(s).Type: GrantFiled: March 30, 2011Date of Patent: March 4, 2014Assignee: Broadcom CorporationInventors: Ahmad Mirzaei, Hooman Darabi
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Patent number: 8665038Abstract: A filtering circuit with BAW type acoustic resonators having at least a first quadripole and a second quadripole connected in cascade, each quadripole having a branch series with a first acoustic resonator of type BAW and a branch parallel with each branch having an acoustic resonator of type BAW, the first acoustic resonator having a frequency of resonance series approximately equal to the frequency of parallel resonance of the second acoustic resonator, the branch parallel of the first quadripole having a first capacitance connected in series with the second resonator and, in parallel with the capacitance, a first switching transistor to short circuit the capacitance.Type: GrantFiled: February 13, 2009Date of Patent: March 4, 2014Assignees: STMicroelectronics S.A., Centre National de la Recherche ScientifiqueInventors: Didier Belot, Alexandre Augusto Shirakawa, Eric Kerherve, Moustapha El Hassan, Yann Deval
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Patent number: 8666346Abstract: An FM receiver is unaware of the modulation level (frequency deviation) of the signal and has to make an estimate of it, or some reasonable time-average of it, and accordingly set the input filter's bandwidth. We calculate modulation by measuring the autocorrelation of the recovered audio signal instead of its peaks, and then applying a peakhold detector. Since FM noise can be modeled to be somewhat uncorrelated, we can expect to get an accurate estimate of signal power while rejecting noise power substantially if we measure a one-sample delayed autocorrelation estimate. Since the above measurement is alike a power measurement, we compute its square root, gain adjust it to obtain a cleaner peak measurement, and then track these clean peaks using a leaky integrator. This gives an estimate of modulation that subdues the effect of the noise.Type: GrantFiled: August 24, 2012Date of Patent: March 4, 2014Assignee: Texas Instruments IncorporatedInventors: Sira Parasurama Rao, John Elliott Whitecar
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Patent number: 8660512Abstract: A filter stage for use in a receiver includes a switch with an input coupled to an antenna terminal, a first output and a second output; a first filter of a first type coupled to the first output; and a second filter of a second type different from the first type, coupled to the second output. A receiver includes a filter stage as mentioned above; and a switching unit coupled to the filter stage for controlling a switching state of the switch, to selectively connect the antenna terminal to the second output, depending on a selection signal.Type: GrantFiled: September 21, 2009Date of Patent: February 25, 2014Inventors: Bernd Adler, Feridoon Jalili, Mikael Bergholz Knudsen, Michael Wilhelm
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Publication number: 20140051378Abstract: Certain disclosed embodiments pertain to suppressing interference in a wireless communication system. For example, a method of suppressing interference can include receiving one or more first signals including components from a plurality of sub-channels. Each of the first signals can be converted into a respective plurality of first sub-band frequency components. A respective spatial filter can be determined for each frequency sub-band using one or more corresponding first sub-band components for each respective spatial filter. One or more second signals including components from the plurality of sub-channels can be received. Each of the second signals can be converted into a respective plurality of second sub-band frequency components. A corresponding plurality of filtered sub-band components can be generated by applying the respective spatial filters to the corresponding second sub-band components for each of the second signals.Type: ApplicationFiled: July 12, 2013Publication date: February 20, 2014Inventors: Babak Daneshrad, Jean-Francois Frigon, Anish Narendra Shah, Weijun Zhu
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Patent number: 8655301Abstract: Systems and methods are disclosed for an electronically adjustable signal filter system, which comprises, in some embodiments, a first filter coupled to an antenna coupling network and a second filter, a power amplifier coupled to the first filter, an antenna connected to an antenna coupling network, a pilot tone generator coupled to the first filter, and a first signal source connected to the power amplifier and first filter. In some embodiments, the power amplifier amplifies the first signal, the first filter places a notch into the first signal transmitted to the antenna coupling network, the antenna coupling network combines the first signal and a second signal received from the antenna and transmits a third signal to the second filter.Type: GrantFiled: June 26, 2013Date of Patent: February 18, 2014Assignee: BlackBerry LimitedInventors: Alain Roussel, Charles W. T. Nicholls
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Patent number: 8654831Abstract: A signal detection apparatus detects the frequency of an input signal without using a PLL. The detection apparatus includes a first and a second orthogonalizer, a phase difference calculator and an integrator, to control the variable coefficient a1 of a band-pass filter. Information e[k]=M·sin(?) representing the phase difference ? between the input data x[k] and the output data y[k] is calculated with the first and second orthogonalizers and the phase difference calculator. The sign of e[k] is inverted and a predetermined integral calculation is performed with the integrator, and the calculated integral value is set as the coefficient a1 of the band-pass filter. Every time input data x[k] is input, the coefficient a1 is changed by reducing it when e[k]>0 and increasing it when e[k]<0. Thus, the frequency of the output signal of the band-pass filter is matched to the input signal.Type: GrantFiled: September 20, 2011Date of Patent: February 18, 2014Assignee: Daihen CorporationInventor: Toyokazu Kitano
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Patent number: 8655299Abstract: A SAW-less receiver includes an FEM interface module, an RF to IF receiver section, and a receiver IF to baseband section. The RF to IF receiver section includes a frequency translated bandpass filter (FTBPF), an LNA, and a mixing section. The FTBPF includes a switching network and a plurality of baseband impedances. The switching network is operable to couple the plurality of baseband impedances to the FEM interface in accordance with a plurality of phase-offset RF clock signals to RF bandpass filter the inbound RF signal. The LNA amplifies the filtered inbound RF signal and the mixing section mixes the amplified inbound RF signal with a local oscillation to produce an inbound IF signal. The receiver IF to baseband section converts the inbound IF signal into one or more inbound symbol streams.Type: GrantFiled: March 30, 2011Date of Patent: February 18, 2014Assignee: Broadcom CorporationInventors: Ahmad Mirzaei, Hooman Darabi
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Patent number: 8654909Abstract: According to an embodiment, a semiconductor integrated circuit includes an amplifier, an interference wave suppression unit, a coupler and a filter control circuit. The interference wave suppression unit includes a filter being controlled to be on or off. The filter is configured to suppress an interference wave component of an amplified signal to output the signal as an output signal when the filter is on. The coupler is configured to detect an input signal or the output signal. The filter control circuit controls the filter to be on when a signal level of a detection input signal or a detection output signal detected by the coupler is greater than or equal to a reference value, and controls the filter to be off when the signal level is smaller than the reference value, at arbitrary determination timing in a period of time between a transmission and a reception.Type: GrantFiled: September 20, 2011Date of Patent: February 18, 2014Assignee: Kabushiki Kaisha ToshibaInventors: Mitsuyuki Ashida, Hideaki Majima
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Patent number: 8655300Abstract: A wireless receiver (110) for UWB or other format, receives a useful signal in a particular band of frequencies in site spite of interference components inside and outside the particular band of frequencies. An interference detector (130, 535, 555) detects the in band interference component in a first range of frequencies to include the particular band of frequencies. The same receiver circuitry (120, 300, 310, 505) is adapted to receive a second range of frequencies to include frequencies adjacent to the particular band, to detect the out of band interference component. The position of a second interfering signal in the second range is used to detect artifacts caused by spectral folding so that the required frequency of a band reject filter can be found.Type: GrantFiled: May 23, 2011Date of Patent: February 18, 2014Assignee: ST-Ericsson SAInventors: Ajay Kapoor, Maurice Stassen
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Patent number: 8655272Abstract: Example embodiments are disclosed for limiting radio frequency noise created during wireless charging of rechargeable batteries in radio frequency communication devices. In an example embodiment, a power source circuit in a wireless charging device produces a source alternating current. The source alternating current is passed through a radio frequency blocking filter to limit radio frequency noise. The filtered source alternating current is then driven through a transmitting coil in the charging device, which inductively couples with a proximately located receiving coil in a radio frequency communication device. An induced alternating current is passed through a second radio frequency blocking filter in the communication device, which limits radio frequency noise that could otherwise be created by the rectifier and control circuits in the communication device.Type: GrantFiled: July 7, 2009Date of Patent: February 18, 2014Assignee: Nokia CorporationInventor: Esa Ilmari Saunamäki
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Patent number: 8644785Abstract: This disclosure relates to low noise amplifiers (LNAs) and more particularly to LNAs integrated on integrated circuit (IC) chips along with radio frequency (RF) amplifiers. In one implementation, an impedance translator is coupled to an amplifier, the impedance translator to cause the amplifier to selectively amplify the one or more components of a received signal.Type: GrantFiled: April 19, 2012Date of Patent: February 4, 2014Assignee: Intel Mobile Communications GmbHInventors: Rastislav Vazny, Krzysztof Dufrene, Hans Pletzer, Werner Schelmbauer, Harald Pretl
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Publication number: 20140024329Abstract: A front end radio architecture is configured to provide a split band frequency arrangement that includes co-banding. The disclosed split band frequency arrangement combines a medium bandwidth filter with a small bandwidth filter to provide enough bandwidth to pass a relatively large communication band. The medium bandwidth filter has a bandwidth that is large enough to support co-banding of smaller communication bands, while also having a narrow enough bandwidth to realize a relatively steep roll-off that ensures coexistence with adjacent bands that are not co-banded. The bandwidths of the medium bandwidth filter and the small bandwidth filter overlap in bandwidth by an amount that is at least as large as the highest bandwidth signal expected to be received or transmitted. The split band frequency arrangement reduces the number of filters needed in the front end radio architecture by repurposing the small bandwidth filter, and by co-banding the smaller communication bands.Type: ApplicationFiled: June 19, 2013Publication date: January 23, 2014Inventor: Nadim Khlat
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Publication number: 20140018029Abstract: Filter coefficients are generated by testing a wireless communication system using single-tone signals. While using the filter coefficients in a filter module, signal imbalance caused by a local oscillator or analog elements in a wireless communication system can be eliminated, so as to prevent the wireless communication system from being affected by the noises.Type: ApplicationFiled: July 8, 2013Publication date: January 16, 2014Inventors: Yuan-Shuo Chang, Wen-Shan Wang
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Patent number: 8630603Abstract: A circuit and method for image frequency rejection is provided that includes an analog dual-quadrature mixer device whose signal inputs for an in-phase-signal and a quadrature-phase signal are connected to an input circuit in the signal path and whose oscillator inputs for an in-phase oscillator signal and a quadrature-phase oscillator signal are connected to a local oscillator device, having an analog adder-amplifier device, which has a number of transistor pairs, in which in each case both transistors of each transistor pair are connected to the same load resistor for the addition of the signals applied at the control inputs of both transistors, and in which the control inputs of both transistors are connected downstream of the outputs of analog dual-quadrature mixer device, and having a multistage analog polyphase filter whose inputs are connected to outputs of the adder-amplifier device.Type: GrantFiled: March 3, 2010Date of Patent: January 14, 2014Assignee: Atmel CorporationInventor: Marco Schwarzmueller
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Patent number: 8626103Abstract: Aspects of the disclosure can provide a second order low pass filter. The second order low pass filter can work in current domain, and have high linearity for in-band signals and out-of-band signals. The second order low pass filter can include a MOS transistor having a gate terminal, a current input terminal and a current output terminal, a first capacitor coupled between the current input terminal and a ground connection and a second capacitor coupled between the gate terminal and the current input terminal.Type: GrantFiled: February 4, 2013Date of Patent: January 7, 2014Assignee: Marvell International Ltd.Inventors: Fernando De Bernardinis, Rinaldo Castello
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Publication number: 20140004812Abstract: Embodiments include a novel receiver architecture to optimize receiver performance in the presence of interference. In various embodiments, the presence of interference is detected, and the relative frequency location of the interference is detected. The relative frequency location specifies whether the frequency of the interference is high side (above the desired signal, i.e., at a higher frequency) or low side (below the desired signal). The receiver is configured based on the detected interference and relative location thereof. For a device such as a cellular phone that operates in a dynamic and changing environment where interference is variable, embodiments advantageously provide the capability to modify the receiver's operational state depending on the interference.Type: ApplicationFiled: July 2, 2012Publication date: January 2, 2014Applicant: Spreadtrum Communications USA Inc.Inventors: David Haub, Zhigang Xu, Jarrett Malone
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Patent number: 8621225Abstract: The present invention is related to a method and apparatus for enhancing security of communications. The apparatus comprises a security processing unit, a data processing unit, a cross-layer watermarking unit, and optionally a smart antenna processor. The security processing unit generates a token/key to be used in watermarking and sends a node security policy to other components. The data processing unit generates user data. The cross-layer watermarking unit includes at least one of Layer-2/3, Layer-1 and Layer-0. Each layer performs a different scheme or degree of watermarking. The cross-layer watermarking unit embeds the token/key into the user data transmission on at least one of the layers selectively in accordance with a security policy.Type: GrantFiled: March 8, 2011Date of Patent: December 31, 2013Assignee: InterDigital Technology CorporationInventors: Sung-Hyuk Shin, Alexander Reznik, Guodong Zhang, Prabhakar R Chitrapu
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Patent number: 8620250Abstract: A filter may be constructed from multiple acoustic elements in parallel. A filtering method may comprise passing a signal to be filtered through such parallel acoustic elements. Such filtering may be applicable to communication devices.Type: GrantFiled: October 27, 2011Date of Patent: December 31, 2013Assignee: Hollinworth Fund, L.L.C.Inventor: Jean-Luc Erb
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Patent number: 8620219Abstract: Provided is a wireless communication system between medical devices. A wireless communication apparatus between medical devices using a cognitive technology may receive, from an external frequency coordination database server, state information of frequencies that are available in a predetermined area, and store interference information associated with the frequencies. The communication apparatus may sense an external interference signal that affects the frequencies outside the predetermined area, and an internal interference signal that affects the frequencies within the predetermined area. The communication apparatus may determine a priority of each of the frequencies that are available in the predetermined area based on the interference information, the external interference signal, and the internal interference signal, and may determine a frequency to be assigned based on the priority.Type: GrantFiled: June 10, 2011Date of Patent: December 31, 2013Assignee: Samsung Electronics Co., Ltd.Inventors: Tae In Hyon, Sung Jin Kim
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Patent number: 8620251Abstract: An electronic device includes an adjustable filter with a first filter element, and a second filter element coupled to the first filter element. The second filter element includes a field effect transistor (FET) including a source terminal, a drain terminal, and a gate terminal. The source terminal and the gate terminal are coupled to a reference voltage. A control circuit is coupled to the drain terminal and is configured to apply a control voltage thereto to vary a capacitance between the source and drain terminals to adjust the adjustable filter.Type: GrantFiled: February 8, 2012Date of Patent: December 31, 2013Assignee: Harris CorporationInventors: Andrew Mui, Anthony Manicone
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Publication number: 20130344829Abstract: An adjustable filter is responsive to a control signal to change a frequency response of the adjustable filter based on frequency spectrum information. The control signal may shift a center of the pass band from a first center frequency to a second center frequency and/or change a pass band bandwidth from a first bandwidth to a second bandwidth. In one example, the frequency spectrum information includes a status of an internal secondary radio. The frequency spectrum information may also indicate a region of operation where the frequency response is selected in accordance with the region.Type: ApplicationFiled: August 26, 2013Publication date: December 26, 2013Applicant: QUALCOMM IncorporatedInventors: Amol Rajkotia, Samir Salib Soliman, Stanley Slavko Toncich
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Publication number: 20130344837Abstract: An adjustable filter is responsive to a control signal to change a frequency response of the adjustable filter based on frequency spectrum information. The control signal may shift a center of the pass band from a first center frequency to a second center frequency and/or change a pass band bandwidth from a first bandwidth to a second bandwidth. In one example, the frequency spectrum information includes a status of an internal secondary radio. The frequency spectrum information may also indicate a region of operation where the frequency response is selected in accordance with the region.Type: ApplicationFiled: August 26, 2013Publication date: December 26, 2013Applicant: QUALCOMM INCORPORATEDInventors: Amol Rajkotia, Samir Salib Soliman, Stanley Slavko Toncich
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Publication number: 20130344836Abstract: An adjustable filter is responsive to a control signal to change a frequency response of the adjustable filter based on frequency spectrum information. The control signal may shift a center of the pass band from a first center frequency to a second center frequency and/or change a pass band bandwidth from a first bandwidth to a second bandwidth. In one example, the frequency spectrum information includes a status of an internal secondary radio. The frequency spectrum information may also indicate a region of operation where the frequency response is selected in accordance with the region.Type: ApplicationFiled: August 26, 2013Publication date: December 26, 2013Applicant: QUALCOMM IncorporatedInventors: Amol Rajkotia, Samir Salib Soliman, Stanley Slavko Toncich
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Publication number: 20130344835Abstract: Embodiments provide a mobile communication device comprising an adaptive filter for filtering a RF signal and a controller. The adaptive filter comprises a first terminal, a second terminal, a reference terminal for providing a reference potential, a first filter structure connected in series between the first terminal and the second terminal, a second filter structure connected in series between the first terminal and the reference terminal, and a third filter structure connected in series between the second terminal and the reference terminal, wherein at least one filter structure of the first, second and third filter structures comprises at least one switchable filter element. The controller is configured to selectively activate or deactivate the at least one switchable filter element based on the RF signal or a baseband version thereof.Type: ApplicationFiled: June 22, 2012Publication date: December 26, 2013Applicant: Infineon Technologies AGInventor: Winfried Bakalski
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Patent number: 8615213Abstract: In one embodiment, the present invention includes a system that having a low noise amplifier (LNA) to receive and amplify a radio frequency (RF) signal, a mixer to receive and downconvert the RF signal to a second frequency signal, a filter to receive and filter the second frequency signal, a demodulator to receive and demodulate the filtered second frequency signal to output demodulated data, and a quality detector to detect a quality of the demodulated data and output a quality indicator based on the data quality. In addition, the system can include a controller coupled to the filter to cause a state of the filter to be stored into a storage responsive to the quality indicator.Type: GrantFiled: September 12, 2011Date of Patent: December 24, 2013Assignee: Silicon Laboratories Inc.Inventors: Hendricus De Ruijter, Ping Xiong
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Publication number: 20130337761Abstract: A communication device includes a receiver that is capable of canceling in-channel interference. The receiver includes an antenna for receiving a wireless signal comprising in-channel components and an out-of-channel component, wherein the in-channel components comprise a desired component and an in-channel interference component. A first filter of the receiver filters the wireless signal by blocking at least a portion of the out-of-channel component to produce a first signal comprising the in-channel components, and at least a second filter of the receiver filters the wireless signal by blocking at least a portion of the in-channel components to produce a second signal comprising the out-of-channel component. An in-channel interference estimator of the receiver generates an in-channel interference estimation signal based on the second signal. And a combiner of the filter combines the first signal and the second signal to at least partially cancel the in-channel interference component of the first signal.Type: ApplicationFiled: June 19, 2012Publication date: December 19, 2013Applicant: MOTOROLA SOLUTIONS, INC.Inventors: Spyros Kyperountas, Neiyer S. Correal, Qicai Shi, Charles L. Sobchak
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Patent number: 8611843Abstract: A filter package for communications equipment includes two or more filters in die form, each having a different frequency response. A first switch and a second switch are operatively connected to the filters and are configured to select a desired filter for operation in a signal stage of the equipment. The filters are aligned and stacked one over the other in the form of a package having an input terminal that is tied to a common terminal of the first switch, and an output terminal tied to a common terminal of the second switch. When the input and the output terminals of the filter package are connected to corresponding terminals of an intermediate frequency (IF) stage in a communications transceiver, the package can support both narrowband and wideband waveforms defined by the Joint Tactical Radio System (JTRS).Type: GrantFiled: April 19, 2012Date of Patent: December 17, 2013Assignee: BAE Systems Information and Electronic Systems Integration Inc.Inventor: Michael S. Vogas
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Patent number: 8611937Abstract: A level detection part 221 detects the field intensity of airwaves broadcast by a desired station, and an AM component extraction part 222 and a level detection part 223 cooperate with one another in detecting the multipath noise level. When the field intensity of the airwaves broadcast by the desired station is high and also the multipath noise level is comparatively low, a filter setting part 229 determines filtering processing to be performed by an adaptive filter part 133 as being FIR type filtering processing. And the filter setting part 229 performs settings for FIR type filtering processing on the adaptive filter part 133. As a result, it is possible to enhance the reproduction quality of the broadcast content sent by the desired station that has been tuned.Type: GrantFiled: March 5, 2010Date of Patent: December 17, 2013Assignee: Pioneer CorporationInventor: Hideyuki Kanno
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Patent number: 8606207Abstract: A filter includes a first port, a second port, a first fractal curve based filter element coupled to the first port, and a second fractal curve based filter element coupled to the second port. The first fractal curve based filter element has first electromagnetic properties and the second fractal curve based filter element has second electromagnetic properties. The first fractal curve based filter element is electromagnetically coupled to the second fractal curve based filter element to filter radio frequency (RF) signals.Type: GrantFiled: February 21, 2011Date of Patent: December 10, 2013Assignee: Broadcom CorporationInventors: Nicolaos G. Alexopoulos, Seunghwan Yoon
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Patent number: 8606321Abstract: Provided is a remote radio head receiver, including an antenna and an interference mitigation block. The antenna is configured to receive a signal. The interference mitigation block is configured to selectively pass and amplify the signal. The interference mitigation block does not include a liquefied gas cooling system.Type: GrantFiled: March 24, 2010Date of Patent: December 10, 2013Assignee: Alcatel LucentInventor: Teppo Lukkarila
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Patent number: 8606208Abstract: There is provided a filter circuit including a passive mixer circuit, and a passive switched capacitor circuit that is connected to a rear stage of the passive mixer and includes a flying capacitor. The passive mixer circuit generates a baseband signal by multiplying an input signal supplied from a predetermined signal source impedance by each local oscillation signal and outputs the baseband signal to the passive switched capacitor circuit, the passive switched capacitor circuit performs predetermined filtering on the baseband signal supplied from the passive mixer circuit and outputs the processed baseband signal, and a capacitance of the flying capacitor of the passive switched capacitor circuit is a capacitance by which input impedance of the passive mixer circuit is matched to the signal source impedance.Type: GrantFiled: July 20, 2012Date of Patent: December 10, 2013Assignee: Sony CorporationInventor: Sachio Iida
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Patent number: 8606211Abstract: A preselect circuit maintains the dynamic range of a received RF input signal during bandpass filtering of the received RF input signal. The preselect circuit includes a Q-deficient passive bandpass filter for coupling to an antenna to receive a received RF input signal. The preselect circuit further includes a Q-enhancement circuit coupled to the Q-deficient passive bandpass filter, wherein the Q-enhancement circuit increases a Q-value of the Q-deficient passive bandpass filter by compensating for resistive inductive losses in the bandpass filter.Type: GrantFiled: June 23, 2009Date of Patent: December 10, 2013Assignee: QUALCOMM IncorporatedInventors: Bruce A. Judson, Cong T. Nguyen
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Patent number: 8600330Abstract: A filter arrangement for filtering a radio signal comprising at least a first filter stage is presented wherein the at least first filter stage comprises a divide stage for dividing a filter stage input signal into several signal portions. The signal portions are filtered in at least two parallel filter elements. A combine stage combines the separate filter output signals into a single filter stage output signal.Type: GrantFiled: October 5, 2011Date of Patent: December 3, 2013Assignee: KATHREIN-Werke KGInventor: Lothar Schmidt
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Patent number: 8600331Abstract: A radio receiver circuit configured to receive a radio frequency signal and produce a baseband signal as an output therefrom has a channel filter having a bandwidth, the channel filter configured to receive the baseband output at a filter input and produce a filtered output at a filter output thereof. A signal-to-noise ratio (SNR) estimator prior to or after the channel filter or both is configured to estimate a signal-to-noise ratio of the baseband signal. A filter controller is configured to receive the signal-to-noise ratio estimate and control the channel filter to adjust the bandwidth thereof in accord with the signal-to-noise ratio estimate. This process thereby assists in improving SNR after the channel filtering by varying the channel filter bandwidth. This abstract is not to be considered limiting, since other embodiments may deviate from the features described in this abstract.Type: GrantFiled: April 11, 2012Date of Patent: December 3, 2013Assignee: Black Berry LimitedInventor: Oleksiy Kravets
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Patent number: 8594605Abstract: The present invention is directed to accurately set a frequency characteristic of a filter integrated in a semiconductor integrated circuit. A semiconductor integrated circuit includes a filter circuit, a cutoff frequency calibration circuit, and a Q-factor calibration circuit. The cutoff frequency calibration circuit adjusts cutoff frequency of the filter circuit to a desired value by adjusting capacitance components of the filter circuit. After adjustment of the cutoff frequency of the filter circuit by the cutoff frequency calibration circuit, the Q-factor calibration circuit adjusts the Q factor of the filter circuit to a desired value by adjusting a resistance component of the filter circuit.Type: GrantFiled: January 25, 2012Date of Patent: November 26, 2013Assignee: Renesas Electronics CorporationInventors: Yusaku Katsube, Kosuke Tsuiji, Yutaka Igarashi, Akio Yamamoto
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Patent number: 8594604Abstract: Capacitive circuits are implemented with desirable quality factors in various implementations. According to an example embodiment, a fringe capacitor includes two capacitive circuits (e.g., plates), respectively having a plurality of capacitive fingers extending from an end structure, and respectively having a connecting pin that is adjacent the connecting pin of the other capacitive circuit, on a common side fringe capacitor. The capacitive fingers are arranged in stacked layers, with vias connecting the fingers in different layers back to the connecting pins.Type: GrantFiled: December 18, 2009Date of Patent: November 26, 2013Assignee: NXP, B.V.Inventors: Edwin van der Heijden, Lukas Frederik Tiemeijer, Maristella Spella
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Patent number: 8594261Abstract: A receiving system and a method for receiving and processing a broadcast signal including mobile service data are disclosed. The receiving system includes a tuner, a demodulator, a block decoder and an RS frame decoder. The tuner receives a broadcast signal including first mobile service data and second mobile service data. The demodulator demodulates the broadcast signal. The block decoder performs turbo-decoding on the first and second mobile service data included in the demodulated broadcast signal. The RS frame decoder builds a primary RS frame by collecting the turbo-decoded first mobile service data and performs error correction decoding on the primary RS frame. The RS frame decoder also builds a secondary RS frame by collecting the second mobile service data and performs error correction decoding on the secondary RS frame.Type: GrantFiled: April 19, 2010Date of Patent: November 26, 2013Assignee: LG Electronics Inc.Inventors: Jin Woo Kim, Byoung Gill Kim, Won Gyu Song, Chul Kyu Mun, Hyoung Gon Lee, In Hwan Choi
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Patent number: 8594606Abstract: A technique for determining a received signal strength from multiple messages filters noise from the received signal to provide an accurate signal strength value. Advantageously, the more accurate output signal strength value can be used to identify movement of a station as well as estimate locations and direction of movement.Type: GrantFiled: April 2, 2012Date of Patent: November 26, 2013Assignee: Trapeze Networks, Inc.Inventor: David B. Aragon
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Patent number: 8588724Abstract: A system and method for improving the processing of communications signals received in the presence of narrowband interference signals. The received communications signals are time sampled and transformed into a series of spectral terms in the frequency domain that are then evaluated to identify narrowband interference signals. The identified narrowband interference terms can be calculated to a value that will optimize the corrupted spectral terms resulting from the communication, and an inverse transformation can be used to generate a time domain signal that is free from interference.Type: GrantFiled: August 19, 2010Date of Patent: November 19, 2013Assignee: Alfred E. Mann Foundation for Scientific ResearchInventors: Phillip B. Hess, Patrick Nercessian
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Patent number: 8588721Abstract: The dual mode receiver channel select filter includes a filter for a dual mode Bluetooth/Wireless Local Area Network (WLAN) receiver portion of a BT/WLAN transceiver. The filter is a 4th order complex filter and is digitally programmable and reconfigurable. Implemented as the channel select filter for dual-mode receivers, the filter adopts low-IF for Bluetooth and zero-IF for WLAN (IEEE 802.11b). It is based on simple active elements, such as current and voltage followers. The center frequency is digitally tuned through programming active current division networks (CDNs).Type: GrantFiled: February 8, 2012Date of Patent: November 19, 2013Assignees: King Fahd University of Petroleum and Minerals, King Abdulaziz City for Science and TechnologyInventor: Hussain Alzaher
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Patent number: 8588723Abstract: A general receiver device with adaptive filter includes an antenna, a low noise amplifier, a bandpass tracking filter, a single-ended-to-differential converter unit, a mixer, and an adaptive filter. The antenna receives an RF signal. The low noise amplifier amplifies the RF signal for generating an amplified RF signal. The band-pass tracking filter filters the amplified RF signal for generating a filtered RF signal. The single-ended-to-differential converter unit converts the filtered RF signal into a differential RF signal. The mixer receives a differential local oscillation signal and uses the differential local oscillation signal to down-convert the differential RF signal into a differential IF signal. The adaptive filter filters the differential IF signal for generating a filtered differential IF signal.Type: GrantFiled: March 8, 2012Date of Patent: November 19, 2013Assignee: Sunplus Technology Co., Ltd.Inventor: Chun-Liang Chen
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Patent number: 8565708Abstract: A filter for filtering a received signal to attenuate an interferer therein, the interferer having a component at an interferer frequency, and the filter comprising: an intermediate filter providing a passband and a stopband; a first frequency converter configured to form a first intermediate signal by frequency-shifting an input signal derived from the received signal such that a component of the input signal at the interferer frequency is shifted to a frequency in the passband of the intermediate filter, and to input the first intermediate signal to the intermediate filter so as to cause the first intermediate signal to be filtered by the intermediate filter to form a second intermediate signal; a second frequency converter configured to form a cancellation signal by frequency-shifting the second intermediate signal such that a component of the second intermediate signal in the passband of the intermediate filter is shifted to the interferer frequency; and a cancellation unit configured to cancel the cancelType: GrantFiled: April 7, 2009Date of Patent: October 22, 2013Assignee: Cambridge Silicon Radio LimitedInventor: Nicolas Sornin
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Patent number: 8565671Abstract: This invention concerns a repeater for radio frequency signals having a channel filter and an active filter connected to the channel filter output. The active filter covers the channels adjacent to the channel filter and includes an amplifier and; two bandpass filters in parallel connected as a negative feedback loop around the amplifier. The first bandpass filter covers the lower adjacent channels and the second bandpass filter covers the higher adjacent channels. The invention notably applies to the development of domestic repeaters for mobile terminals meeting the DVB-H digital television standard.Type: GrantFiled: June 19, 2008Date of Patent: October 22, 2013Assignee: Thomson LicensingInventors: Jean-Luc Robert, Jean-Yves Le Naour, Philippe Minard
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Patent number: 8565814Abstract: One embodiment relates to a circuit for efficient wireless communication. The circuit includes an antenna interface module adapted to receive multiple frequency components via an antenna. Multiple reception paths stem from the antenna interface module, where different reception paths are associated with different frequency components. The circuit also includes multiple filter elements having inputs respectively coupled to the multiple reception paths. At least two of the filter elements cooperatively form a differential output signal based on their respective frequency components. Other methods and systems are also disclosed.Type: GrantFiled: August 28, 2008Date of Patent: October 22, 2013Assignee: Intel Mobile Communications GmbHInventors: Weimin Tang, Ern Teng Chu, Hon Kong Lok, Wei Dong Chen
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Patent number: 8565681Abstract: Embodiments of the invention may provide for reducing interference in the front-end of a communications receiver. The cancellation circuitry may be utilized in conjunction with a preliminary rejection filter for improved rejection of out-of-band interference from other radio services or circuitry. The cancellation circuit may be placed in parallel with the preliminary rejection filter and may enhance suppression at the interference frequency by matching the gain and phase of the preliminary rejection filter prior to subtracting the matched signal from the preliminary rejection filter output. The cancellation circuit need not necessary know beforehand the characteristics of the preliminary rejection filter, the interference source, or the coupling mechanism, as it may adapt to unknown or varying interferers by adapting the matching gain and phase values based on the output of the preliminary rejection filter at tap points occurring both before and after application of the cancellation signal.Type: GrantFiled: March 25, 2010Date of Patent: October 22, 2013Assignee: Samsung Electro-MechanicsInventors: Andrew Joo Kim, Yunseo Park, Seongmo Yim, Youngsik Hur
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Patent number: 8565709Abstract: A passive filter circuit filters an input signal to attenuate an undesired frequency. The passive filter circuit includes a first stage and a second stage. The input to the first stage is the input signal. The first stage includes a first inductor and a first branch coupled to the output of the first inductor. The first branch includes a first capacitor and a second inductor. The first stage is coupled to the second stage. The second stage includes a third inductor and a second branch coupled to the output of the third inductor. The second branch includes a second capacitor. Other embodiments are also described and claimed.Type: GrantFiled: February 9, 2011Date of Patent: October 22, 2013Assignee: Apple Inc.Inventors: Scott P. Mullins, Timothy M. Johnson, Yehonatan Perez
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Patent number: 8565710Abstract: A SAW-less transmitter includes an up-conversion mixing module, a frequency translated BPF (FTBPF), an output module, and a power amplifier driver. The up-conversion mixing module converts an outbound symbol stream into an up-converted signal. The FTBPF frequency translates a baseband filter response to an RF bandpass filter response and filter the up-converted signal in accordance with the RF bandpass filter response to produce a filtered up-converted signal. The output module conditions the filtered up-converted signal to produce a conditioned up-converted signal. The power amplifier driver amplifies the conditioned up-converted signal to produce an outbound RF signal.Type: GrantFiled: March 30, 2011Date of Patent: October 22, 2013Assignee: Broadcom CorporationInventors: Ahmad Mirzaei, Mohyee Mikhemar, Hooman Darabi