With Response Weighting Means Patents (Class 333/196)
  • Patent number: 7728699
    Abstract: A longitudinally coupled resonator acoustic wave filter device that utilizes an inter-IDT resonance mode with a reduced insertion loss has a structure in which apodization weights are assigned in first to third IDTs having narrow pitch electrode finger portions in portions other than the narrow pitch electrode finger portions, such that the electrode finger overlap width sequentially varies in an acoustic wave propagating direction in which an acoustic wave propagates, and portions of the IDTs located at ends adjacent to the narrow pitch electrode finger portions have a maximum electrode finger overlap width.
    Type: Grant
    Filed: January 26, 2009
    Date of Patent: June 1, 2010
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Yasuhisa Fujii, Masaru Yata
  • Patent number: 7721411
    Abstract: A method of manufacturing an acoustic wave device includes: forming a conductive pattern on a wafer made of a piezoelectric substrate having an acoustic wave element, the conductive pattern including a first conductive pattern being continuously formed on a cutting region for individuating the wafer, a second conductive pattern being formed on an electrode region where a plated electrode is to be formed and being connected to the acoustic wave element and a third conductive pattern connecting the first conductive pattern and the second pattern; forming an insulating layer on the wafer so as to have an opening on the second conductive pattern; forming the plated electrode on the second conductive pattern by providing an electrical current to the second conductive pattern via the first conductive pattern and the third conductive pattern; and cutting off and individuating the wafer along the cutting region.
    Type: Grant
    Filed: November 28, 2007
    Date of Patent: May 25, 2010
    Assignees: Fujitsu Media Devices Limited, Fujitsu Limited
    Inventors: Shunichi Aikawa, Jyouji Kimura, Keiji Tsuda, Kazunori Inoue, Takashi Matsuda
  • Patent number: 7653118
    Abstract: A surface acoustic wave (SAW) expander based transmitter and correlator based receiver comprises SAW devices that perform expander or correlator functions based on the types of signals inputted to the SAW devices. The SAW devices incorporate chirp with adaptive interference and programmable coding capabilities. The SAW devices and method of operating the devices allow the implementation of very low power radios that overcome problems with temperature drift, lithography constraints and interference and jamming suffered by prior art implementations.
    Type: Grant
    Filed: March 23, 2005
    Date of Patent: January 26, 2010
    Assignee: Cypress Semiconductor Corporation
    Inventors: Steve Whelan, Paul Beard
  • Patent number: 7623037
    Abstract: A surface acoustic wave sensor or tag having multiple transducer/antenna pairs each having a different center frequency. The bandwidth of each transducer/antenna pair is inversely proportional to the number of transducer/antennas pairs used and the bandwidth is the sum of the bandwidth of the transducer/antenna pairs. Implementing a SAW sensor or tag with multiple transducer/antenna pairs significantly reduces device losses and improves the performance of the device since the individual transducer/antenna pair's fractional bandwidth is reduced by the ratio of the system bandwidth to the number of transducer antenna pairs used in the sensor.
    Type: Grant
    Filed: September 15, 2006
    Date of Patent: November 24, 2009
    Assignee: University of Central Florida Research Foundation, Inc.
    Inventor: Donald C. Malocha
  • Patent number: 7620094
    Abstract: Disclosed is a spread spectrum clock generator which includes: a first delay control type oscillator that variably controls an oscillation period at a control period interval according to a control signal; a control circuit; a maximum modulation value determination circuit that determines a maximum modulation value from a predetermined value, a frequency control signal, and a given modulation degree setting signal; a modulation signal generation circuit that receives the maximum modulation value from the maximum modulation value determination circuit and generates a modulation control signal within the maximum modulation value; and a second delay control type oscillator that receives a value obtained by adding the modulation control signal from the modulation signal generation circuit to the frequency control signal as a control signal and variably controls the oscillation period of an output clock signal at the control period interval according to the control signal.
    Type: Grant
    Filed: July 7, 2005
    Date of Patent: November 17, 2009
    Assignee: NEC Electronics Corporation
    Inventor: Satoshi Yoneda
  • Patent number: 7606294
    Abstract: Channel quality can be detected accurately in a wireless transmission system such as an HSDPA method. In the case of estimating a channel quality of a signal transmitted by a Code Division Multiple Access method and of estimating the channel quality in a system having a synchronization channel not orthogonal to a channel receiving data, a noise component of a desired channel is estimated; degree of a noise component caused by the synchronization channel is estimated with respect to the estimated noise; and a channel quality of a receiving channel is detected based on the estimated degree of the noise component.
    Type: Grant
    Filed: April 21, 2005
    Date of Patent: October 20, 2009
    Assignee: Sony Ericsson Mobile Communications Japan, Inc.
    Inventor: Takeshi Kokubo
  • Patent number: 7586992
    Abstract: An apparatus and method for channel estimation and CP reconstruction in an OFDM-STBC mobile communication system are provided. An ISI canceller cancels ISI signal components from first and second received symbol sequences. A cyclicity restorer cancels ICI signal components from the ISI-cancelled first received symbol sequence and the ISI-cancelled second received symbol sequence. A recoverer acquires the recovered sequence estimates of the ICI-cancelled first received symbol sequence and the ICI-cancelled second received symbol sequence by decoding. The ICI cancellation of the ISI-cancelled first and second received symbol sequences and the ISI cancellation of the second received symbol sequence are iterated a predetermined number of times.
    Type: Grant
    Filed: January 19, 2006
    Date of Patent: September 8, 2009
    Assignees: Samsung Electronics Co., Ltd, Postech Foundation
    Inventors: Jong-Hyung Kwun, Eung-Sun Kim, Jong-Hyeuk Lee, Gi-Hong Im, Hui-Chul Won
  • Patent number: 7586972
    Abstract: A code division multiple access (CDMA) communication system using spread spectrum signaling over a communication bandwidth uses two different signal spectra generated using two different respective spreading code formats, such as NRZ code formatting and staggered Manchester code formatting, for respectively providing nonsplit spectra having a center peak and split spectra having a center null. The spectra are combined during transmission as a CDMA communication signal having a composite spectrum. The use of different code formats produces the composite spectrum of respective center peak and center null spectra that enables increased channel capacity.
    Type: Grant
    Filed: February 11, 2004
    Date of Patent: September 8, 2009
    Assignee: The Aerospace Corporation
    Inventors: Srinivasa H. Raghavan, Jack K. Holmes, Kristine P. Maine
  • Patent number: 7580444
    Abstract: The invention provides an adaptive frequency hopping spread-spectrum (FHSS) transmission system and method, which efficiently utilizes available transmission bandwidth, whilst providing robustness to jamming techniques in wireless communication systems. The proposed technique operates by transmitting a wide-band signal over multiple, single-carrier, parallel transmission subbands, which may occupy non-contiguous frequency regions. The proposed scheme exhibits significant gain in error rate performance, as compared to a data rate equivalent single-subband system in the presence of signal jamming and/or interference without a reduction in the transmission data rate nor an increase in transmitter power. In addition, the proposed system and method are adaptive and enable more efficient use of the available bandwidth for communicating, thus increasing the overall bandwidth utilization of the system.
    Type: Grant
    Filed: February 17, 2006
    Date of Patent: August 25, 2009
    Assignee: Her Majesty the Queen in right of Canada, as represented by the Minister of Industry, through the Communications Research Centre Canada
    Inventors: Colin Brown, Philip Vigneron
  • Patent number: 7555824
    Abstract: Methods for integrating quartz-based resonators with electronics on a large area wafer through direct pick-and-place and flip-chip bonding or wafer-to-wafer boding using handle wafers are described. The resulting combination of quartz-based resonators and large area electronics wafer solves the problem of the quartz-electronics substrate diameter mismatch and enables the integration of arrays of quartz devices of different frequencies with the same electronics.
    Type: Grant
    Filed: August 9, 2006
    Date of Patent: July 7, 2009
    Assignee: HRL Laboratories, LLC
    Inventors: David T. Chang, Randall L. Kubena
  • Patent number: 7555029
    Abstract: A method and a standard radio wave receiver for receiving a plurality of standard radio waves respectively having signal configurations in accordance with respective specifications which define carrier channels and formats and for decoding time code signals carried by the standard radio waves. The method extracts at least part of a bit waveform common to the specifications as a extracted signal from a waveform of each of the time code signals given by each of the carrier channels, synchronizes bits to each of the time code signals in accordance with the extracted signal, determines an evaluation index indicating good or bad of a reception condition for each of the carrier channels from the bit waveform, and selects a single channel from the carrier channels in accordance with the evaluation index.
    Type: Grant
    Filed: November 29, 2005
    Date of Patent: June 30, 2009
    Assignee: Oki Semiconductor Co., Ltd.
    Inventor: Takayuki Kondo
  • Patent number: 7551665
    Abstract: An ultra wideband (UWB) receiver system operable to process a high order Gaussian pulse includes an integrator group, a correlator circuit and a comparator circuit. The integrator group includes an input coupled to receive the high order Gaussian pulse and an output coupled to the correlator circuit, the integrator group having two or more successively coupled integration stages, each integration stage operable to integrate, over a predefined time period, the signal received thereby, the integrator group operable to output, in response, a lower order Gaussian pulse. The correlator circuit is coupled to receive the lower order Gaussian pulse, and is operable to output a correlated output signal corresponding to the correlation between the lower order Gaussian pulse and a predefined reference signal.
    Type: Grant
    Filed: November 10, 2004
    Date of Patent: June 23, 2009
    Assignee: Agency for Science, Technology and Research
    Inventor: Tong Tian
  • Patent number: 7532090
    Abstract: In an acoustic wave filter device, first and second longitudinally coupled resonator SAW filters are provided on a piezoelectric substrate. The first and second longitudinally coupled resonator SAW filters are connected in parallel to each other. The first and second longitudinally coupled resonator SAW filters are withdrawal-weighted. The withdrawal weighting in at least the longitudinally coupled resonator SAW filter is different from the withdrawal weighting in the other longitudinally coupled resonator SAW filter.
    Type: Grant
    Filed: June 15, 2007
    Date of Patent: May 12, 2009
    Assignee: Murata Manufacturing Co., Ltd.
    Inventor: Yuichi Takamine
  • Patent number: 7522021
    Abstract: A surface acoustic wave apparatus has a configuration by which the spurious of the higher-order transverse modes is suppressed and a SAW excitation intensity distribution is not changed in the propagation direction. The surface acoustic wave apparatus has at least one interdigital transducer, which is disposed such that a plurality of comb-shape electrodes respectively connected to common electrodes are interleaved, wherein a region with the plurality of interleaved comb-shape electrodes has a first overlapping region with a overlapping length constant over a whole area along a propagation direction of a surface acoustic wave and a second overlapping region formed on at least one side of the first overlapping region with a overlapping length weighted in the propagation direction of the surface acoustic wave, and wherein an overlapping-length weighting envelope curve in the second overlapping region has at least two changing points in the propagation direction of the surface acoustic wave.
    Type: Grant
    Filed: February 8, 2006
    Date of Patent: April 21, 2009
    Assignees: Fujitsu Media Devices Limited, Fujitsu Limited
    Inventors: Koichi Wada, Seiichi Mitobe, Shogo Inoue
  • Patent number: 7519097
    Abstract: The invention relates to a spread-signal multiplexing circuit for frequency-multiplexing a plurality of spread signals that were generated in parallel according to the SSMA scheme. An object of the invention is to adapt to various degrees of multiplicity and to keep the SN ratio and the power efficiency high. To this end, a spread-signal multiplexing circuit of the invention comprises an amplitude monitoring part for multiplexing a plurality of spread signals and determining amplitude of a resulting signal in time-series order; a delaying part for delaying the spread signals in parallel by a time that is equal to a propagation delay time of the amplitude monitoring part; and a multiplexing part for generating a multiplexed signal by multiplexing the delayed spread signals while weighting the delayed spread signals in parallel using weights that are smaller as an average value of the determined amplitude is larger.
    Type: Grant
    Filed: October 24, 2002
    Date of Patent: April 14, 2009
    Assignee: Fujitsu Limited
    Inventors: Yasuyuki Oishi, Tokuro Kubo, Kazuo Nagatani
  • Patent number: 7518471
    Abstract: A surface acoustic wave filter (cascaded dual mode SAW filter) includes three IDT electrodes disposed adjacent to each other along the propagation direction of a surface wave on a piezoelectric substrate and two primary-tertiary longitudinally-coupled dual mode SAW filters cascaded and constructed by arranging grating reflectors on both sides of three IDT electrodes. At least a pair of electrode fingers are thinned out from the IDT electrodes disposed outside, and floating electrodes are then disposed.
    Type: Grant
    Filed: April 6, 2006
    Date of Patent: April 14, 2009
    Assignee: Epson Toyocom Corporation
    Inventor: Naoki Takahashi
  • Patent number: 7505506
    Abstract: A method of generating a composite signal includes the steps of: (a) generating a plurality of sub-carriers, each sub-carrier having a different frequency position in a frequency spectrum; (b) generating a plurality of codes; and (c) forming a plurality of code combinations from the plurality of codes generated in step (b). The method also includes the steps of (d) first modulating each sub-carrier using a respective one of the code combinations formed in step (c) to form a plurality of modulated sub-carriers; and (e) second modulating in-phase and quadrature components of a base carrier using the plurality of modulated sub-carriers to form the composite signal having multiple carriers. The composite signal is a constant envelope signal, and a single sideband signal.
    Type: Grant
    Filed: February 25, 2005
    Date of Patent: March 17, 2009
    Assignee: ITT Manufacturing Enterprises, Inc.
    Inventors: Goran Djuknic, Chi Chiu Chan, Robert W. Smid
  • Patent number: 7501917
    Abstract: A SAW filter is configured by forming a first IDT and a second IDT on a piezoelectric substrate, and the first IDT is arranged between one terminal of input/output terminals and another terminal of the input/output terminals, i.e., serially in a signal path, and the second IDT is arranged in parallel to a signal path from a portion between one terminal of the input/output terminals and the first IDT. The first IDT and the second IDT are arranged in proximity to each other and on the same propagation path of surface acoustic waves which are excited by each of the resonators.
    Type: Grant
    Filed: November 18, 2004
    Date of Patent: March 10, 2009
    Assignee: Panasonic Corporation
    Inventors: Kazunori Nishimura, Tsutomu Igaki, Ken Matsunami, Hiroyuki Nakamura
  • Patent number: 7501916
    Abstract: An elastic wave device includes at least one IDT electrode provided on a piezoelectric substrate. The at least one IDT electrode includes first and second electrode fingers arranged next to each other in a propagation direction of elastic wave. The side edges of at least the electrode finger of the first and second electrode fingers are provided with projections. The position of the projections in the longitudinal direction of the electrode fingers substantially corresponds with the position of a gap in the longitudinal direction of the electrode fingers, the gap being provided at the tip end of the electrode finger of the first and second electrode fingers.
    Type: Grant
    Filed: August 23, 2007
    Date of Patent: March 10, 2009
    Assignee: Murata Manufacturing Co., Ltd.
    Inventor: Hajime Kando
  • Patent number: 7490390
    Abstract: A manufacturing method is provided for a voltage controlled oscillator comprising an thin film BAW resonator and a variable capacitor element. The thin film BAW resonator includes an anchor section formed on a Si substrate, a lower electrode supported on the anchor section and positioned to face the Si substrate, a first piezoelectric film formed on the lower electrode, and an upper electrode formed on the first piezoelectric film. The variable capacitor element includes a stationary electrode formed on a Si substrate, an anchor section formed on the Si substrate, a first electrode supported on the anchor section and positioned to face the Si substrate, a second piezoelectric film formed on the first electrode, and a second electrode formed on the second piezoelectric film.
    Type: Grant
    Filed: April 27, 2007
    Date of Patent: February 17, 2009
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Takashi Kawakubo, Kazuhide Abe, Mayumi Morizuka
  • Patent number: 7489213
    Abstract: A surface acoustic wave (SAW) filter includes a transducer having an acoustic track to pass a SAW. A center frequency of the filter excites the SAW. The acoustic track includes cells along a longitudinal direction of the acoustic track. Each cell has electrode fingers. The cells include different cell types, where a cell type is defined by a connection sequence of electrode fingers of a cell. At least some of the cells are functional cells, each for exciting and/or reflecting the SAW. There are at least two functional cells, each of which includes at least one wide electrode finger and at least one narrow electrode finger. A reflective strength of a target functional cell is configurable by changing a width of an electrode finger in the target functional cell but by maintaining an overall width of the target functional cell substantially constant.
    Type: Grant
    Filed: August 20, 2004
    Date of Patent: February 10, 2009
    Assignee: Epcos AG
    Inventor: Thomas Ebner
  • Patent number: 7482896
    Abstract: A surface acoustic wave apparatus has a configuration by which the spurious of the higher-order transverse modes is suppressed and a SAW excitation intensity distribution is not changed in the propagation direction. The surface acoustic wave apparatus has at least one interdigital transducer; a region with the plurality of interleaved comb-shaped electrodes is formed with two regions which are a first overlapping region and a second overlapping region with overlapping-lengths weighted along a propagation direction of a surface acoustic wave; the first overlapping region and the second overlapping region are in contact or overlapped in a direction vertical to the propagation direction of the surface acoustic wave; and in either the first or the second overlapping region, an overlapping-length weighting envelope curve has at least two or more changing points in the propagation direction of the surface acoustic wave.
    Type: Grant
    Filed: March 6, 2006
    Date of Patent: January 27, 2009
    Assignees: Fujitsu Media Devices Limited, Fujitsu Limited
    Inventors: Koichi Wada, Seiichi Mitobe, Shogo Inoue
  • Patent number: 7479855
    Abstract: In a longitudinally-coupled-resonator-type elastic wave filter device, at least one of two IDTs which are adjacent to each other is provided with a dummy electrode for series weighting in a portion in which the IDTs are adjacent to each other, and at least one of series-weighted portions includes at least one of metallization ratio reducing portion in a first acoustic track and metallization ratio increasing portion in a second acoustic track so as to reduce the difference between the metallization ratio of the first acoustic track passing through a connecting portion of the dummy electrode and the metallization ratio of each of second and third acoustic tracks each placed on either side of the first acoustic track in the direction of propagation of an elastic wave.
    Type: Grant
    Filed: July 17, 2008
    Date of Patent: January 20, 2009
    Assignee: Murata Manufacturing Co., Ltd.
    Inventor: Masaru Yata
  • Publication number: 20080315973
    Abstract: A surface acoustic wave filter includes a piezoelectric substrate including lithium niobate, a series resonator including a first interdigital transducer electrode provided on the piezoelectric substrate, and a parallel resonator including a second interdigital transducer electrode provided on the piezoelectric substrate and being electrically connected to the series resonator. An apodized weighting factor of the first interdigital transducer electrode is smaller than an apodized weighting factor of the second interdigital transducer electrode. This surface acoustic wave filter has a small loss.
    Type: Application
    Filed: June 6, 2008
    Publication date: December 25, 2008
    Applicant: Matsushita Electric Industrial Co., Ltd.
    Inventors: Hiroyuki NAKAMURA, Tetsuya TSURUNARI, Ken MATSUNAMI, Hidekazu NAKANISHI
  • Patent number: 7463672
    Abstract: A radio communication method and system for transmitting multiple-user digital data information in a Code Division Multiple Access (CDMA) format over multipath and mutual-interfering channels to a receiving terminal with diversity antennas and equalization signal processing. At the receiving terminal, diversity antenna signals are grouped into time blocks and replicas are generated of the user-unique CDMA sequence signals for a set of K mutually interfering users. Within each time block the multiuser channel is estimated, equalization parameters are calculated, and decision-feedback equalization is used to produce multiuser estimates associated with a subset ? of the K users. These estimates are deinterleaved and error-correction decoded to recover transmitted digital data information for the subset of ? users.
    Type: Grant
    Filed: March 16, 2005
    Date of Patent: December 9, 2008
    Inventor: Peter Monsen
  • Patent number: 7453333
    Abstract: A surface acoustic wave apparatus comprises a piezoelectric substrate 17 on the bottom face of which IDT electrodes 3 and 4 and an annular ground electrode 6 which encloses the IDT electrodes 3 and 4 and is connected to the IDT electrode 3, and a base substrate on the top face of which an annular ground conductor 7 is formed and which has an internal ground conductor layer 10a and a bottom face ground conductor layer 11a connected to the annular ground conductor 7 and an internal ground conductor layer 10b and a bottom face ground conductor layer 11b connected to the IDT electrode 4. A first ground conductor composed of the internal ground conductor layer 10a and the bottom face ground conductor layer 11a is electrically separated from a second ground conductor composed of the internal ground conductor layer 10b and the bottom face ground conductor layer 11b. The apparatus has an excellent out-of-band attenuation characteristic.
    Type: Grant
    Filed: August 23, 2005
    Date of Patent: November 18, 2008
    Assignee: Kyocera Corporation
    Inventors: Hiroyuki Tanaka, Kiyohiro Iioka
  • Patent number: 7436273
    Abstract: A SAW chip (11) where ones are balanced signal terminals and the others are unbalanced signal terminals is mounted on a mounting board (12) in a flip chip manner, and the mounting board (12) and a surface of the SAW chip are covered with resin (19). At that time, grounds of first and second SAW filters (1, 2) in the SAW chip (11) are connected together and an annular pattern (14) is formed so as to surround a signal pattern of the SAW chip (11) on the mounting board (12) on which the SAW chip (11) is mounted, and the annular electrode (14) is connected to a ground pattern.
    Type: Grant
    Filed: September 1, 2005
    Date of Patent: October 14, 2008
    Assignee: Epson Toyocom Corporation
    Inventor: Yasuhide Onozawa
  • Patent number: 7429905
    Abstract: An acoustic wave filter device includes a piezoelectric substrate and a longitudinally coupled resonator surface acoustic wave filter unit provided on the piezoelectric substrate. The surface acoustic wave filter unit includes first to fifth IDTs arranged in a surface wave propagation direction. The first, third, and fifth IDTs are connected to an unbalanced terminal, while the second and fourth IDTs are connected to first and second balanced terminals, respectively. The second IDT includes first and second sub-IDT portions obtained by dividing the second IDT and arranged in a crossing width direction, and the fourth IDT includes first and second sub-IDT portions obtained by dividing the fourth IDT and arranged in the crossing width direction. The first and second sub-IDT portions are connected in series. The first and second sub-IDT portions are also connected in series.
    Type: Grant
    Filed: June 7, 2007
    Date of Patent: September 30, 2008
    Assignee: Murata Manufacturing Co., Ltd.
    Inventor: Teruhisa Shibahara
  • Publication number: 20080122558
    Abstract: A surface acoustic wave device comprises a surface acoustic wave element, including: a piezoelectric substrate, a first interdigital transducer unit having a first interdigital transducer and a second interdigital transducer formed on the piezoelectric substrate, and a second interdigital transducer unit having a third interdigital transducer and a fourth interdigital transducer formed on the piezoelectric substrate; a first terminal electrically coupled to the first interdigital transducer; a second terminal electrically coupled to the second interdigital transducer; a first variable resistor electrically coupling the first terminal to the third interdigital transducer; a second variable resistor electrically coupling the first terminal to the fourth interdigital transducer; a third variable resistor electrically coupling the second terminal to the third interdigital transducer; and a fourth variable resistor electrically coupling the second terminal to the fourth interdigital transducer.
    Type: Application
    Filed: November 29, 2007
    Publication date: May 29, 2008
    Applicant: EPSON TOYOCOM CORPORATION
    Inventors: Katsuro Yoneya, Shinji Nishio, Masahiro Onuki
  • Patent number: 7372897
    Abstract: The number of times for averaging operation for averaging a correlation value of a received signal and a reference signal is properly controlled. When the correlation value is not averaged, since a lower limit value TH_A of a correlation level of a distribution of timings of which a path exists is larger than an upper limit value TH_B of a correlation level of a distribution of timings of which a path does not exist, the correlation value of a path is hidden by noise. Since the averaging operation is repeated until the relation of TH_A>TH_B is satisfied, the averaging operation is stopped when the relation is satisfied. The TH_A and TH_B are decided in accordance with RSCP and ISCP of a pilot channel and RSSI of a received base band signal.
    Type: Grant
    Filed: May 14, 2004
    Date of Patent: May 13, 2008
    Assignee: Sony Ericsson Mobile Communications Japan, Inc.
    Inventor: Hiroyuki Fukada
  • Patent number: 7372347
    Abstract: A surface acoustic wave (SAW) device includes a piezoelectric substrate, a first and a second interdigital transducers (IDT) provided thereon. The second IDT has a side that is substantially aligned with a corresponding side of the first IDT, and another side of the second IDT is arranged so that the second IDT may adjust a leaked wave caused resulting from by a power-flow angle of the piezoelectric substrate.
    Type: Grant
    Filed: November 16, 2004
    Date of Patent: May 13, 2008
    Assignee: Fujitsu Media Devices Limited
    Inventors: Satoshi Orito, Tsuyoshi Oura, Toru Takezaki, Satoshi Ichikawa, Hirotada Wachi, Toshifumi Tanaka, Koichi Wada
  • Patent number: 7352800
    Abstract: A method of Partial Parallel Interference Cancellation (PPIC) is provided for recursively eliminating the Multiple Access Interference from a received signal. Such method is to use a recursion way to eliminate all the Multiple Access Interference (MAI) one by one from the received signal. Moreover, the present invention is to take the output of the pre-stage as the input of the present stage with the recursion method so that we can use only one operating circuit to obtain the function the MAI eliminating.
    Type: Grant
    Filed: May 12, 2004
    Date of Patent: April 1, 2008
    Assignee: BenQ Corporation
    Inventors: Yih-Min Chen, Hsu-Ching Wang, Chun-Cheng Chen, Fu-Yen Kuo
  • Patent number: 7330089
    Abstract: In a balanced acoustic wave filter device, first and second acoustic wave filter sections that are connected in parallel to an unbalanced terminal are connected to first and second balanced terminals, respectively. The first and second surface acoustic wave filter sections are configured such that the phases of the first and second balanced terminals differ by 180 degrees. The first and second acoustic wave filter sections are longitudinally coupled resonator-type acoustic wave filter sections each including a plurality of IDTs disposed in a direction in which acoustic waves propagate.
    Type: Grant
    Filed: February 7, 2007
    Date of Patent: February 12, 2008
    Assignee: Murata Manufacturing Co., Ltd.
    Inventor: Masaru Yata
  • Patent number: 7271685
    Abstract: A transversal surface acoustic wave filter includes an input-side interdigital electrode, an output-side interdigital electrode, and a shield electrode, which are provided on a surface wave substrate. The distance between an excitation point of the input-side interdigital electrode, which is closest to the shield electrode, and an intermediate point between the shield electrode-side end of the input-side interdigital electrode and the input-side interdigital electrode-side end of the shield electrode is in the range of about 0.8? to about 0.975?, wherein ? is the wavelength of a surface wave.
    Type: Grant
    Filed: January 3, 2007
    Date of Patent: September 18, 2007
    Assignee: Murata Manufacturing Co., Ltd.
    Inventor: Nobunari Tanaka
  • Patent number: 7236067
    Abstract: A surface acoustic wave filter capable of obtaining a low insertion loss and wide bandwidth characteristic is provided. The surface acoustic wave filter includes a piezoelectric substrate; a pair of reflective electrodes formed on the piezoelectric substrate; and a plurality of comb electrodes formed between the pair of reflective electrodes on the piezoelectric substrate, wherein, in regard to the neighboring two comb electrodes among the plurality of comb electrodes, an electrode pitch of one comb electrode is set so that continuously varying phases of surface acoustic waves respectively generated by the two comb electrodes are obtained in a gap opposite to an outermost finger electrode of the other neighboring comb electrode.
    Type: Grant
    Filed: April 25, 2006
    Date of Patent: June 26, 2007
    Assignee: Fujitsu Media Devices Limited
    Inventors: Masanori Ueda, Osamu Kawachi, Motoyuki Tajima, Kenya Hashimoto, Takuya Abe
  • Patent number: 7218188
    Abstract: Microelectromechanical system (MEMS) apparatus and methods for surface acoustic wave (SAW) switching are disclosed. The apparatus includes a piezoelectric substrate having spaced apart input and output SAW transducers. A MEMS switch is arranged between the input and output SAW transducers The MEMS switch has a deformable member in electromagnetic communication with one or more actuation electrodes formed on or above the substrate. The deformable member is deformable to mechanically contact the substrate to deflect or absorb a SAW generated by the input SAW transducer.
    Type: Grant
    Filed: January 18, 2005
    Date of Patent: May 15, 2007
    Assignee: Intel Corporation
    Inventors: Qing Ma, Dong S. Shim
  • Patent number: 7194793
    Abstract: A method for adjusting a frequency characteristic of an edge reflection type surface acoustic wave device includes the step of obtaining a frequency characteristic of an edge reflection type surface acoustic wave device having a piezoelectric substrate. The edge reflection type surface acoustic wave device has a pair of edges of the piezoelectric substrate which define a predetermined distance therebetween. The piezoelectric substrate is cut at a position which defines a distance that is shorter than the predetermined distance when a final frequency characteristic of the edge reflection type surface acoustic wave device is to be higher than the obtained frequency characteristic. The piezoelectric substrate is cut at a position which defines a distance that is longer than the predetermined distance when a final frequency characteristic of the edge reflection type surface acoustic wave device is to be lower than the obtained frequency characteristic.
    Type: Grant
    Filed: May 13, 2004
    Date of Patent: March 27, 2007
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Michio Kadota, Yasunori Takakuwa, Seigo Hayashi, Junya Ago, Hideya Horiuchi, Mamoru Ikeura
  • Patent number: 7170372
    Abstract: An electro-acoustic transducer for a component operating with surface waves, in particular for a surface wave filter, in which, to suppress interfering excitation ensuing in the gap region adjacent an end of a finger, a variation of the gaps is implemented with regard to at least one feature selected from transversal arrangement, size and shape. Due to the slight dimension change of the position of the gap in comparison to the finger length, the desired primary excitation in the transducer remains approximately unchanged, however the interfering excitation is displaced or divided, and made ineffectual.
    Type: Grant
    Filed: May 21, 2002
    Date of Patent: January 30, 2007
    Assignee: EPCOS AG
    Inventors: Werner Ruile, Thomas Bauer, Michael Jakob, Ulrike Rösler
  • Patent number: 7154360
    Abstract: A filter includes a piezoelectric substrate, and interdigital transducers (IDTs) that are formed on the piezoelectric substrate. At least one of the IDTs has a main electrode finger pattern that is weighted. The IDT having the main electrode finger pattern also has a sub electrode finger pattern that is connected in parallel to the main electrode finger pattern, and generates a surface acoustic wave that cancels a surface acoustic wave caused by leakage electric fields generated in the main electrode finger pattern.
    Type: Grant
    Filed: September 28, 2004
    Date of Patent: December 26, 2006
    Assignee: Fujitsu Media Devices Limited
    Inventors: Koichi Wada, Satoshi Ichikawa, Hirotada Wachi, Tohru Takezaki, Tsuyoshi Oura, Toshifumi Tanaka, Satoshi Orito
  • Patent number: 7132908
    Abstract: RF programmable SAW filters achieve selectable filter performance by providing tunable input and output interdigital (IDTs) with different synchronous frequencies and substantially reduce electromagnetic interference (EMI) associated with RF signals not of interest. The RF programmable SAW filter includes tunable input and output IDT's, with the input and output IDT's having different input and output IDT synchronous frequencies. The input signal is divided into multiple output signals along multiple signal paths that are applied to an input tap weight network wherein the amplitude of each output signal may be varied individually. The individually weighted signal paths are then applied one each to individual IDT input electrode fingers in a means for IDT input, which is characterized by a synchronous frequency Fin. The IDT input means generates an acoustic wave that propagates to a means for IDT output, which is characterized by a synchronous frequency Fout, where Fin and Fout are not the same.
    Type: Grant
    Filed: September 16, 2004
    Date of Patent: November 7, 2006
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: John A. Kosinski, Robert A. Pastore, Jr., Hong-Liang Cui
  • Patent number: 7061346
    Abstract: The invention provides a surface wave transversal filter having an input transducer and an output transducer in which the input transducer has a primary weighting which determines the transfer function and in which the output transducer is provided with a low secondary weighting in order to improve the trap characteristic.
    Type: Grant
    Filed: April 10, 2002
    Date of Patent: June 13, 2006
    Assignee: EPCOS AG
    Inventor: Michael Schemies
  • Patent number: 7030539
    Abstract: In a surface acoustic wave device, a common portion and a strip portion of a reflector electrode are partially cut off to increase a space between the electrodes. The increase of the space between the electrodes reduces the influence of the amount of charges and the influence of an unbalance between the amounts of charges in etching of a metallic film, thereby preventing the electrodes from having a curved shape in section. Consequently, the surface acoustic wave device has a reduced propagation loss.
    Type: Grant
    Filed: September 26, 2002
    Date of Patent: April 18, 2006
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Mitsuhiro Furukawa, Kiyoharu Yamashita, Kazushi Nishida, Hiroshi Kurotake
  • Patent number: 7023300
    Abstract: Very low passband ripple is provided in a wide bandwidth high frequency SAW FIR filter using slanted finger IDTs by one or more of three techniques: cancelling regenerated SAWs at parallel-connected input IDTs of two SAW filters which are similar except for a quarter-wavelength difference in spacing of the input and output IDTs, this difference varying with wavelength across the IDT aperture; shaping edges of shield electrodes to provide quarter-wavelength differences in, and hence cancellation of, SAWs reflected at the edges, the differences varying with wavelength across the IDT aperture; and making pairs of slanted shield electrodes symmetrical to compensate for refraction of SAWS by the shield electrodes.
    Type: Grant
    Filed: December 15, 2004
    Date of Patent: April 4, 2006
    Inventors: Chun-Yun Jian, Steve A. Beaudin, Somsack Sychaleun
  • Patent number: 7002282
    Abstract: A surface acoustic wave device includes a surface acoustic wave filter element having a piezoelectric substrate on which comb-like electrodes are formed, and a package having a first cavity in which the surface acoustic wave filter is housed. The package includes a flexible chip mounting base having a first surface on which the surface acoustic wave filter is mounted and having a thickness equal to or less than 100 ?m.
    Type: Grant
    Filed: January 27, 2004
    Date of Patent: February 21, 2006
    Assignee: Fujitsu Media Devices Limited
    Inventor: Naoyuki Mishima
  • Patent number: 6985048
    Abstract: A longitudinally-coupled-resonator-type surface acoustic wave filter includes three interdigital transducers provided on a piezoelectric substrate in the direction in which surface acoustic waves propagate. An interdigital transducer disposed at the approximate center among the three interdigital transducers of the longitudinally-coupled-resonator-type surface acoustic wave filter is divided into two parts substantially symmetrically in the propagation direction of the surface acoustic waves and the two parts are connected to balanced signal terminals, respectively. Left and right interdigital transducers of which the polarities are inverted relative to each other are connected to an unbalanced signal terminal to provide a balanced-to-unbalanced conversion function. A reactance component provided on the piezoelectric substrate, inside a package, or outside the package is connected to either of the balanced signal terminals.
    Type: Grant
    Filed: August 29, 2003
    Date of Patent: January 10, 2006
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Yuichi Takamine, Teruhisa Shibahara
  • Patent number: 6967545
    Abstract: Surface acoustic wave (SAW) zebra-wave-guide (10) implemented as an array of interdigitized electrode fingers, wherein the array has internal inter-finger connectors (18) providing inside electrical shorting of part of fingers (16) remaining other fingers (14) to be isolated, moreover, the array (12) is bordered by important free surface spaces (15). Time delay and phase of the propagating SAW beam front are controlled by the varying of quantity of isolated fingers (14) of the zebra-wave-guide (10). Aggregation (40) of the parallel zebra-wave-guides having different quantities of isolated fingers (14) and different widths allows manipulations with narrow SAW beams' phases and magnitudes, that becomes helpful degree of freedom for desire transformation of the SAW beam (140).
    Type: Grant
    Filed: November 29, 2001
    Date of Patent: November 22, 2005
    Inventor: Yuri Abramov
  • Patent number: 6967427
    Abstract: A surface acoustic wave filter device includes balanced signal terminals, and surface acoustic wave filters respectively connected to the balanced signal terminals, and at least one surface acoustic wave resonator connected between at least one of the balanced signal terminals and a ground terminal.
    Type: Grant
    Filed: March 18, 2003
    Date of Patent: November 22, 2005
    Assignee: Murata Manufacturing Co., Ltd.
    Inventor: Masaru Yata
  • Patent number: 6946931
    Abstract: A surface acoustic wave resonator includes a piezoelectric substrate, and a SAW resonator having an interdigital transducer. The interdigital transducer satisfies 0.15L?W?0.45L where W is the total of widths of all electrode fingers that form the interdigital transducer, and L is a length of the said interdigital transducer in a direction of SAW propagation.
    Type: Grant
    Filed: December 11, 2002
    Date of Patent: September 20, 2005
    Assignees: Fujitsu Limited, Fujistu Media Devices Limited
    Inventors: Shogo Inoue, Jun Tsutsumi, Takashi Matsuda, Osamu Ikata
  • Patent number: 6946930
    Abstract: A reliable SAW device has excellent reflection and a small size, which is achieved by reducing the number of fingers defining reflectors, such that losses due to a large electromechanical coupling coefficient are small and the film thickness of electrodes has much less effect on frequencies of the device. In the SAW device having pluralities of first fingers and second fingers, disposed on a quartz substrate, constituting an IDT for exciting SH waves and reflectors for reflecting the SH waves, respectively, the first and second fingers made mainly from Al are disposed on the ST-cut 90° X-propagation quartz substrate with the Euler angles (0°, ?, 90°±2°), wherein the angle ? is within the range of about 110° to about 150°, and a normalized film thickness (H/?) of the fingers is within in the range of about 0.025 to about 0.135.
    Type: Grant
    Filed: April 26, 2002
    Date of Patent: September 20, 2005
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Michio Kadota, Takeshi Nakao
  • Patent number: 6946932
    Abstract: In a substrate in which a reflection coefficient ? of a surface acoustic wave per electrode is small, the invention obtains a Q value or a CI value level, which is equivalent to or higher than that of a related art product, at a device size which is equivalent to the related art product which addresses the problem that the size of a surface acoustic wave resonator becomes larger. A surface acoustic wave resonator includes one interdigital transducer to excite a surface acoustic wave in a propagation direction x on a piezoelectric plate and a pair of reflectors arranged on both sides thereof in the propagation direction. The interdigital transducer is divided into three regions. The electrode fingers of the interdigital transducer of each region are formed at a fixed pitch which differs within 2%. The surface acoustic wave resonator possesses a single peak response.
    Type: Grant
    Filed: October 7, 2003
    Date of Patent: September 20, 2005
    Assignee: Seiko Epson Corporation
    Inventors: Michiaki Takagi, Yoshio Maeda, Takashi Yamazaki, Keigo Iizawa