Frequency Modifying Or Conversion Patents (Class 455/313)
  • Publication number: 20090023412
    Abstract: A diversity FM radio receiver comprises two tuners for simultaneously tuning to the same FM channel. To avoid disturbances between the local oscillator signals of the tuners and to be able to use standard IF filters, one of the tuners operate with high-side LO injection and the other tuner operates with low-side LO-injection. To equalize the frequencies of the signals to be subjected to the diversity operation the two IF-signals of the tuners are fed to complex mixers with oppositely rotating phases.
    Type: Application
    Filed: January 22, 2007
    Publication date: January 22, 2009
    Applicant: NXP B.V.
    Inventors: Pieter Meijer, Gerrit Groot Hulze, Jacobus C. Sandee
  • Patent number: 7471939
    Abstract: A multiplier includes a first input terminal which receives a modulated signal, three second input terminals which receive first, second, and third local signals respectively, the first, second, and third local signals having a phase difference of 120° from one another, a multiplication unit configured to multiply the modulated signal by each of the first, second, and third local signals, and output first, second, and third multiplied output signals, and three output terminals from which the first, second, and third multiplied output signals are derived, respectively.
    Type: Grant
    Filed: March 22, 2006
    Date of Patent: December 30, 2008
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Takafumi Yamaji, Hidenori Okuni
  • Patent number: 7469136
    Abstract: Methods in intermediate frequency and direct conversion receivers for reducing pre-selection filter leakage and harmonic coupling to a programmable voltage controlled oscillator by mixing a receive signal at a mixer having a mixer injection frequency outside a pre-selection filter passband. In some applications, the mixer injection frequency is conditionally moved outside the pre-selection filter passband. In other applications, signal gain is increased to compensate for any loss resulting from shifting the mixer injection frequency outside the pre-selection passband.
    Type: Grant
    Filed: November 30, 2001
    Date of Patent: December 23, 2008
    Assignee: Motorola, Inc.
    Inventors: Matt Hayek, Deven Patel
  • Publication number: 20080311876
    Abstract: A signal receiver for use in a 60 GHz wireless area network, in which the received RF signal band (100) is converted to a plurality of intermediate frequency (IF) sub-bands (104) and then processing (LPF, AGC, ADC) in the analogue domain of the sub-bands (104) is performed in parallel. As a result, the design requirements of the analogue components are significantly relaxed and it is possible to perform gain control in respect of each sub-band (104), which improves the quality of the received signal.
    Type: Application
    Filed: March 16, 2006
    Publication date: December 18, 2008
    Applicant: NXP B.V.
    Inventors: Dominicus M.W. Leenaerts, Cornelis H. Van Berkel
  • Patent number: 7457605
    Abstract: A receiver (200) includes a transconductance mixer (310), a polyphase filter (320), and a transimpedance amplifier (330). The transconductance mixer (310) mixes a radio frequency (RF) voltage signal into a current signal having a plurality of phases using a local oscillator signal. The polyphase filter (320) filters the current signal to provide a filtered current signal. The transimpedance amplifier (330) converts the filtered current signal into an output voltage signal.
    Type: Grant
    Filed: September 10, 2004
    Date of Patent: November 25, 2008
    Assignee: Silicon Laboratories, Inc.
    Inventors: Charles D. Thompson, Edward Kim Fung Lee
  • Patent number: 7449974
    Abstract: Provided are an on-chip balun, a transceiver using the on-chip balun, and a method for fabricating the on-chip balun. The on-chip balun includes: a first metal winding including a port grounded and a port to which an unbalanced signal is input; a second winding outputting an induced current generated by the first metal winding as two signals having about equal intensity and a phase difference of about 180°; and a ground shield positioned between the first and second metal windings and having a symmetric structure so as to generate a symmetric parasitic capacitance between the ground shield and the second metal winding. The ground shield can be inserted between the first and second metal windings to remove an asymmetrical parasitic capacitance so as to reduce a phase imbalance and a gain imbalance of an output value of the second metal winding. As a result, a highly balanced on-chip balun can be fabricated.
    Type: Grant
    Filed: January 12, 2006
    Date of Patent: November 11, 2008
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Jae-sup Lee, Dong-hyun Lee, Seong-soo Lee
  • Patent number: 7450925
    Abstract: A receiver includes first switches for applying either differential signals of an oscillator or a data signal of a transmitter to down-converting mixers; a frequency conversion unit for mixing and applying to the down-converting mixers quadrature signals generated from an arbitrary clock signal generator and the oscillator, and having a PPF for changing a phase difference of I/Q signals according to a control voltage externally applied; a phase difference detection part for checking a phase difference between the I/Q signals and generating the control voltage to be applied to the PPF according to the phase difference so as to correct the phase difference; third switches for applying the data signal processed through the down-converting mixers, filters, and amplifiers to A/D converters and applying the I/Q signals having a predetermined frequency to the phase difference detection part; and a control unit for switching the first and third switches.
    Type: Grant
    Filed: January 24, 2006
    Date of Patent: November 11, 2008
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Hyun-su Chae, Hoon-tae Kim, Eun-chul Park
  • Publication number: 20080268806
    Abstract: A digital radio frequency memory (DFRM) which converts an incoming analog radio frequency signal to a fourteen bit digital signal allowing for digital signal processing and then retransmitted as an analog RF signal. The DFRM provides a time delay for RF signals by storing the signal. The DFRM also changes the signal frequency in the range of plus or minus 100,000 KHz which places a doppler on the signal. The signal phase is changed in a range of 0 to 359 degrees by the DFRM.
    Type: Application
    Filed: July 24, 2007
    Publication date: October 30, 2008
    Inventor: Roger Dean Durtschi
  • Patent number: 7444126
    Abstract: In a video IF channel the gain of the circuit is achieved ahead of the IF filter and the output of the filter, including its noise, need only be amplified a relatively small amount, thus preserving an acceptable signal to noise ratio. In one embodiment, a variable gain amplifier is used as the first stage amplifier and a fixed gain amplifier is used for the output stage.
    Type: Grant
    Filed: December 22, 1995
    Date of Patent: October 28, 2008
    Assignee: Microtune (Texas), L.P.
    Inventor: Adam Stanislaw Wyszynski
  • Patent number: 7439813
    Abstract: Apparatus and method for generating first, second and third carrier frequencies of 3432 MHz, 3960 MHz and 4488 MHz respectively, for use in a wireless transmission system deploy only first and second PLLs which are configured to generate 6336 MHz and 2640 MHz signals respectively with only in-phase components. Frequency dividers are employed for frequency-dividing the 6336 MHz signal severally by 2, 4, and 12 to obtain frequency-divided intermediate outputs with both in-phase and quadrature components. The intermediate output components and other intermediate signal components are selectively combined in a mixer (e.g., a single side-band mixer), for deriving the first, second and third carrier frequencies of 3432 MHz, 3960 MHz and 4488 MHz with both in-phase and quadrature components. The invention has application in UWB, WPAN, WLAN, or other wireless systems and has the simplicity and advantages of using only two PLLs instead of the prior art arrangements of three PLLs.
    Type: Grant
    Filed: May 2, 2006
    Date of Patent: October 21, 2008
    Assignee: Wipro Limited
    Inventor: Awadh Pandey
  • Patent number: 7433667
    Abstract: A signal conditioning circuit contains an oscillator which is connected to the inputs of two mixers. The output of one mixer is coupled, so as to form a feedback path, to a frequency divider circuit whose first output is coupled to the second input of the first mixer. A second signal output of the frequency divider circuit carries a signal with a phase shift of 90 degrees with respect to the signal at the first signal output of the frequency divider circuit. The second signal is supplied to a second input of the second mixer. Feedback results in undesirable signal components in the in-phase and quadrature components being suppressed. At the same time, the in-phase and quadrature components have a fixed phase relationship with respect to one another. The signal conditioning circuit allows desired non-integer division ratios to be achieved.
    Type: Grant
    Filed: September 23, 2004
    Date of Patent: October 7, 2008
    Assignee: Infineon Technologies AG
    Inventors: Dietolf Seippel, André Hanke, Duyen Pham-Stäbner
  • Patent number: 7428308
    Abstract: Apparatus and method for transmitting and reproducing stereophonic audio signals are disclosed. The method comprises splitting first and second channels into two frequency bands, combining the lower frequency band signals of the two channels, and transmitting the combined signals of the two channels or signals representative thereof. The apparatus comprises: a splitter for splitting each of the two channels into two frequency bands, a combiner, for combining the lower frequency band signals of the two channels, and a transmitter for transmitting the combined signals, or signals representative thereof, and the higher frequency band signals of the two channels, or signals representative thereof.
    Type: Grant
    Filed: January 10, 2003
    Date of Patent: September 23, 2008
    Assignee: Zarlink Semiconductor Limited
    Inventors: Marcus Richard Jones, Terence Christopher Aliwell
  • Publication number: 20080227421
    Abstract: A receiver to recover a signal of interest while consuming reduced power in some scenarios. The receiver contains a in-phase channel processing path and a quadrature phase channeling path for down converting an input signal to an intermediate frequency, and then recovering the signal of interest by further processing of the input signal at intermediate frequency. One of the two paths is turned off upon occurrence of a desired condition, which reduces power consumption. In an embodiment, the condition is that the input signal does not contain an image signal of the signal of interest.
    Type: Application
    Filed: March 13, 2008
    Publication date: September 18, 2008
    Applicant: TEXAS INSTRUMENTS INCORPORATED
    Inventor: Jaiganesh Balakrishnan
  • Publication number: 20080227409
    Abstract: This disclosure describes techniques for reducing adverse effects of TX signal leakage in a full-duplex, wireless communication device. The techniques make use of a notch filter to reject TX signal leakage in a signal processed in the RX path of the wireless communication device. The notch filter may be constructed as a complex notch filter using passive resistor and capacitor components to produce a notch frequency that attenuates TX signal leakage components in a desired signal. The notch filter may be applied to a down-converted, baseband signal produced by a passive mixer.
    Type: Application
    Filed: July 12, 2007
    Publication date: September 18, 2008
    Applicant: QUALCOMM INCORPORATED
    Inventors: Li-Chung Chang, Prasad S. Gudem, Jose Cabanillas
  • Patent number: 7424281
    Abstract: An integrated semiconductor image-rejection mixer having high linearity and high gain. In addition to the components of a classic image-rejection architecture, the present mixer has a high-frequency current-diverting stage that permits the operation of the output stage with high conversion gain and sufficient headroom for good linearity, even in cases where the supply voltage is relatively low (such as 3 V). The conversion gain of the mixer and its image-rejection performance can be changed by changing the load resistances and the elements of the output polyphase network, with minor effects on linearity and no change in power consumption or DC levels. The power consumption of the image-rejection mixer is low because no additional DC current is required for buffers or amplifier stages.
    Type: Grant
    Filed: November 29, 2005
    Date of Patent: September 9, 2008
    Assignee: Maxim Integrated Products, Inc.
    Inventor: Bernard Duggan
  • Patent number: 7421250
    Abstract: A radio frequency (RF) integrated circuit (IC) includes a local oscillation module, analog radio receiver, analog radio transmitter, digital receiver module, digital transmitter module, and digital optimization module. The local oscillation module is operably coupled to produce at least one local oscillation. The analog radio receiver is operably coupled to directly convert inbound RF signals into inbound low intermediate frequency signals based on the local oscillation. The digital receiver module is operably coupled to process the inbound low IF signals in accordance with one of a plurality of radio transceiving standards to produce inbound data. The digital transmitter is operably coupled to produce an outbound low intermediate frequency signal by processing outbound data in accordance with the one of the plurality of radio transceiving standards. The analog radio transmitter is operably coupled to directly convert the outbound low IF signals into outbound RF signals based on the local oscillation.
    Type: Grant
    Filed: September 9, 2005
    Date of Patent: September 2, 2008
    Assignee: Broadcom Corporation
    Inventor: Hong Shi
  • Patent number: 7418250
    Abstract: Because there are different voltages at two current output terminals of a current divider, the voltages at the current input terminals of two current switch circuits are not affected mutually even with a large amplitude of local signals. Accordingly, the performance of a quadrature mixer can be enhanced by increasing the amplitude of the local signals. Bias currents are supplied to the two current switch circuits through the current divider from a common DC current source which essentially supplies a bias current to a V/I converter and, therefore, power consumption is reduced.
    Type: Grant
    Filed: February 9, 2007
    Date of Patent: August 26, 2008
    Assignee: Renesas Technology Corp.
    Inventors: Yutaka Igarashi, Isao Ikuta, Akio Yamamoto
  • Patent number: 7415261
    Abstract: A mixer for use in a transceiver comprises an LO switching pair and a folded transconductor. The mixer can be used as an upconversion or down conversion mixer and provides increased headroom and linearity, while still reducing current consumption. The mixer can be configured for differential inputs and outputs and the folded transconductor can comprises a MOSFET differential pair.
    Type: Grant
    Filed: March 31, 2005
    Date of Patent: August 19, 2008
    Assignee: Conexant Systems, Inc.
    Inventors: Ray Rosik, Mark Santini, Weinan Gao
  • Patent number: 7409198
    Abstract: A method (700, 1100) and apparatus (300) are provided in a receiver for applying a variable gain to a received signal including a transmitted codeword in accordance with an Ultra Wideband (UWB) protocol. A first signal is generated and input to a selectable gain stage including a series of selectable 0 dB and 9 dB gain elements (302-305). The first signal includes the received signal mixed with a local oscillator signal modified according to a reference codeword. A gain value is selected from the selectable gain stage to amplify the first signal and form a second signal. An output signal is generated by combining the second signal and the modified local oscillator signal.
    Type: Grant
    Filed: August 30, 2005
    Date of Patent: August 5, 2008
    Assignee: Freescale Semiconductor, Inc.
    Inventors: John W. McCorkle, Phuong T. Huynh
  • Patent number: 7398075
    Abstract: In a radio wave reception device and a radio wave clock capable of receiving multiple frequencies, an intermediate frequency signal whose frequency is fixed can be output while a signal output from a local oscillation circuit (5) is fixed.
    Type: Grant
    Filed: August 8, 2003
    Date of Patent: July 8, 2008
    Assignee: Casio Computer Co., Ltd.
    Inventor: Kaoru Someya
  • Patent number: 7398073
    Abstract: A low noise mixer comprises a first mixer core configured to receive a radio frequency (RF) input signal having an RF frequency, and a first local oscillator signal, wherein the first local oscillator signal is at a frequency that is nominally twice the frequency of the RF frequency, the first mixer core configured to switch the RF input signal to at least one secondary mixer core at a frequency that coincides with the frequency of the first local oscillator signal, the at least one secondary mixer core configured to receive the switched RF input signal and a second local oscillator signal, where the second local oscillator signal is at the same nominal frequency as the RF input signal, and wherein switching the RF input signal at the frequency of the first local oscillator signal substantially eliminates flicker noise associated with the down-conversion process.
    Type: Grant
    Filed: September 6, 2005
    Date of Patent: July 8, 2008
    Assignee: Skyworks Solutions, Inc.
    Inventors: Rajasekhar Pullela, Tirdad Sowlati, Dmitriy Rozenblit
  • Patent number: 7395043
    Abstract: A modem generates a new RSSI threshold value in response to a flag signal representing the quality of the threshold value indicated by the result of error detection supplied from one monitor, and supplies the generated threshold value to another monitor. The RSSI threshold value set in the other monitor is rendered variable, the modem thus being able to operate with the threshold value converging precisely in a short time.
    Type: Grant
    Filed: September 29, 2005
    Date of Patent: July 1, 2008
    Assignee: Oki Electric Industry Co., Ltd.
    Inventor: Tsuyoshi Atsumi
  • Publication number: 20080152054
    Abstract: Providing interferer diversity is disclosed. A received wireless signal is processed to obtain a first processed signal in which a desired information is translated to a first frequency in a first Nyquist zone. The received wireless signal processed to obtain a second processed signal in which the desired information is translated to a second frequency in the first Nyquist zone. The second frequency is different than the first frequency.
    Type: Application
    Filed: December 20, 2006
    Publication date: June 26, 2008
    Inventors: Jeff Franck, William Keese
  • Publication number: 20080151984
    Abstract: A sampling rate conversion system reduces the signal processing burdens carried by cellular phones, headsets, and other electronic devices. Because the system consumes fewer resources to convert between signal sampling rates, the system may significantly reduce processing time and resource requirements in the device. As a result, the device may instead devote resources to performing other useful tasks, such as interacting with the user through a graphical user interface and performing selected processing tasks.
    Type: Application
    Filed: September 14, 2007
    Publication date: June 26, 2008
    Inventors: Gerhard Uwe Schmidt, Mohamed Krini, Martin Rossler
  • Patent number: 7392026
    Abstract: A multi-band high gain mixer and quadrature signal generator allows a receiver system to receive signals at multiple frequency bands without requiring significant hardware duplication. A single mixer directly receives any of three communication frequency bands such as Universal Mobile Telecommunication System (UMTS), Personal Communication Services (PCS), Digital Communication System (DCS), and Japan and US W-CDMA 800 bands without amplification. A Serial-Parallel Interface selectably forwards RF signals within the receiver's frequency channels to the mixer for demodulation into in-phase (I) and quadrature (Q) signals at a common IF output from the multi-mode receiver. Significant power and cost advantages are attained by elimination of duplicate mixers and amplifier stages.
    Type: Grant
    Filed: April 4, 2005
    Date of Patent: June 24, 2008
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Mohammed S. Alam, Daniel L. Kaczman
  • Patent number: 7392032
    Abstract: Provided is a digital signal processing device, specifically a modular application specific integrated circuit (“ASIC”), having a programmable crosspoint switch for facilitating data transfer and processing within the circuit. A programmable matrix element is operable to perform advanced matrix operations (arithmetic operations) according to user provided commands. The crosspoint switch interconnects the programmable matrix element with various other processing or conditioning modules (i.e. down conversion, filter, pulse processing and demodulation modules) to ensure parallel processing at System Clock rates. The ASIC, which is reconfigurable at a top-level according to user requirements, facilitates design changes and bench testing.
    Type: Grant
    Filed: December 30, 2005
    Date of Patent: June 24, 2008
    Assignee: L3 Communications Corporation
    Inventor: Jerry W. Yancey
  • Patent number: 7391320
    Abstract: The present invention is a method and system for controlling a RC device via a secure radio link. In one embodiment of the invention, spread spectrum modulation may be employed which may provide a digital radio frequency (RF) link between a controller and a RC device. A controller may be coupled with a transmitter module and a radio controlled device may be coupled with a receiver module in accordance with the present invention to provide an add-on upgrade capability. The method and system for controlling a RC device may also include error detection and correction, interpolation of lost packets, failsafe technology and force-feedback telemetric technology to further enhance the user experience with radio controlled devices.
    Type: Grant
    Filed: October 18, 2005
    Date of Patent: June 24, 2008
    Assignee: Horizon Hobby, Inc.
    Inventors: Paul Beard, John Adams, Mathew Lee, Eric Meyers
  • Publication number: 20080146185
    Abstract: Receivers (5) for simultaneously receiving different radio frequency signals according to different standards are provided with first frequency translating stages (1) for converting the radio frequency signals into first intermediate frequency signals and second frequency translating stages (2) for converting the first intermediate frequency signals into second intermediate frequency signals and processing stages (3) for retrieving first information from the first intermediate frequency signals and second information from the second intermediate signals. As a result, such receivers (5) have relatively low power consumption. The first frequency translating stages (1) comprise first oscillators (19) and first mixers (11) and further first mixers (12). The second frequency translating stages (2) comprise second oscillators (29) and second mixers (21) and further second mixers (22) and third mixers (23) and further third mixers (24).
    Type: Application
    Filed: February 6, 2006
    Publication date: June 19, 2008
    Applicant: KONINKLIJKE PHILIPS ELECTRONICS, N.V.
    Inventors: Paul Van Zeijl, Neil Bird
  • Publication number: 20080139150
    Abstract: Certain aspects of a method and system for mitigating effects of pulling in multiple phase locked loops in multi-standard systems may include selecting an input frequency range of operation at a voltage controlled oscillator based on a particular wireless band of operation in a system that handles a first wireless communication protocol and a second wireless communication protocol. An image rejection mixer may be enabled to generate an output signal for the particular wireless band of operation based on mixing a plurality of received signals within a selected frequency range. An in-phase (I) component and a quadrature (Q) component of the generated output signal may be generated by utilizing a RC-CR quadrature network.
    Type: Application
    Filed: December 29, 2006
    Publication date: June 12, 2008
    Inventors: Qiang Li, Razieh Roufoogaran, Arya Behzad, Dandan Li, Hung-Ming Chien
  • Publication number: 20080139159
    Abstract: Aspects of a method and system for configurable Active/Passive Mixer and Shared GM Stage may include configuring an RF mixer in frequency demodulator to operate in an active mode or a passive mode. An in-phase (I) processing path and a quadrature (Q) processing path of the RF mixer may utilize a single shared GM stage.
    Type: Application
    Filed: December 31, 2006
    Publication date: June 12, 2008
    Inventors: Adedayo Ojo, Madjid Hafizi, Arya Behzad
  • Publication number: 20080139119
    Abstract: Aspects of a method and system for processing signals in a high performance receive chain may include amplifying radio frequency signals in amplifier chains in a multistandard radio frequency front-end, comprising one or more shared processing stages, and combining, with substantially equal gain, a number of phase-shifted radio frequency signals of the radio frequency signals into substantially equal-gain-combined radio frequency signals. The substantially equal-gain-combined radio frequency signals may be demodulated to obtain inphase channels and quadrature channels. A number of inphase channels and quadrature channels may be processed in I-channel processing blocks and Q-channel processing blocks to generate an output analog baseband signal. The multistandard radio frequency front-end may be capable of processing Bluetooth® signals and Wireless Local Area Network (WLAN) signals.
    Type: Application
    Filed: April 9, 2007
    Publication date: June 12, 2008
    Inventors: Arya Behzad, Adedayo Ojo, Yuyu Chang, Hung-Ming Chien, Kishore Rama Rao, Guruprasad Seetharam
  • Patent number: 7386292
    Abstract: Methods, systems, and apparatuses, for down-converting and up-converting an electromagnetic signal. In embodiments the invention operates by receiving an EM signal and recursively operating on approximate half cycles of the carrier signal. The recursive operations can be performed at a sub-harmonic rate of the carrier signal. The invention accumulates the results of the recursive operations and uses the accumulated results to form a down-converted signal. In embodiments, up-conversion is accomplished by controlling a switch with an oscillating signal, the frequency of the oscillating signal being selected as a sub-harmonic of the desired output frequency. When the invention is being used in the frequency modulation or phase modulation implementations, the oscillating signal is modulated by an information signal before it causes the switch to gate the bias signal. The output of the switch is filtered, and the desired harmonic is output.
    Type: Grant
    Filed: October 25, 2004
    Date of Patent: June 10, 2008
    Assignee: ParkerVision, Inc.
    Inventors: David F. Sorrells, Michael J. Bultman, Robert W. Cook, Richard C. Looke, Charley D. Moses, Jr., Gregory S. Rawlins, Michael W. Rawlins
  • Patent number: 7386291
    Abstract: An off-chip signal is provided to a differential branch-line directional coupler implemented entirely on-chip. The coupler produces differential quadrature signals, which are then buffered and applied to a quadrature mixer. The coupler is implemented entirely on-chip using microstrip transmission lines. The coupler is made up of a plurality of rings and a plurality of underpasses connecting ports of the rings, wherein each of the plurality of rings is made up of four branch lines, and each branch line having an electrical length of one-quarter wavelength at the center design frequency. Coupling between the plurality of branch lines of the rings may be varied.
    Type: Grant
    Filed: September 2, 2003
    Date of Patent: June 10, 2008
    Assignee: International Business Machines Corporation
    Inventors: Brian Allan Floyd, Ullrich Richard Pfeiffer, Scott Kevin Reynolds, Thomas Martin Zwick
  • Publication number: 20080130607
    Abstract: Aspects of a method and system for multimode DC offset compensation are presented. Aspects of the system may include accumulating a selected number of signal samples, determining an average of the accumulated signal samples, and keeping a running total of the average for use feedback signal generation. The signal samples may be, for example, samples of WCDMA signals. By keeping track of the signal offset error, the signal offset error, or residual DC, may be determined. For example the signal offset error may comprise a DC component and/or a sinusoidal component. The number of signal samples to accumulate for the average may be based on the signal offset error. For example, a threshold may be determined as part of design of an embodiment of the invention.
    Type: Application
    Filed: November 30, 2006
    Publication date: June 5, 2008
    Inventors: Junqiang Li, Nelson Sollenberger, Li Fung Chang
  • Patent number: 7382175
    Abstract: A frequency mixer includes a first N channel MOS transistor, second and third N channel MOS transistors constituting a local oscillator signal differential pair, and having substantially identical properties, a first load, and a second load. The first N channel MOS transistor receives an RF signal at its gate. A local oscillator signal is applied to the gates of the second and third N channel MOS transistors. The drain current of the second and third N channel MOS transistors is output to the drain of the first N channel MOS transistor. An amplitude-current conversion circuit receives the RF signal and provides an output current to the drain of the first N channel MOS transistor to decrease monotonously the output current with respect to the amplitude of the RF signal.
    Type: Grant
    Filed: March 18, 2005
    Date of Patent: June 3, 2008
    Assignee: Renesas Technology Corp.
    Inventors: Takaya Maruyama, Hisayasu Sato
  • Publication number: 20080125071
    Abstract: A signal frequency band detection device is disclosed that is able to separately handle plural co-existing signals, and able to separately detect frequency bands used for transmission of these co-existing signals. The signal frequency band detection device includes a signal decomposition unit that decomposes a received signal into plural signal components with frequency bands of the signal components at least partially overlapping each other; and a frequency band detection unit that, based on respective electrical powers of the signal components, detects the respective frequency bands of the signal components.
    Type: Application
    Filed: May 29, 2007
    Publication date: May 29, 2008
    Applicant: NTT DoCoMo, Inc.
    Inventors: Koji Maeda, Anass Benjebbour, Takahiro Asai
  • Patent number: 7379726
    Abstract: The present invention provides a passive RFID chip with on-chip charge pumps for generating electrical power for the chip from radio frequencies. The passive RFID chip comprises an analog portion and a digital portion. The analog portion primarily comprises a voltage sensor and an AM data detector. The digital portion comprises a state machine digital logic controller. Incoming RF signals enter the chip via external antennas. The RF signals are converted into regulated DC signals by RF-DC converters with the voltage sensor. The RF-DC converters provide power for all the on-chip components and hence the chip does not require external power supply. The incoming RF signals are demodulated by demodulators and enter the AM data detector where the envelope transitions are detected. A voltage alarm is provided to ensure the voltage level does not drop below an operational level of the chip.
    Type: Grant
    Filed: July 18, 2007
    Date of Patent: May 27, 2008
    Assignee: MStar Semiconductor, Inc.
    Inventors: Sterling Smith, Henry Tin-Hang Yung
  • Patent number: 7379727
    Abstract: An RF front-end receiver comprises a low noise amplifier and a local oscillator driver, which are connected to respective input ports of a mixer which comprises a first and second transistor with gates coupled to one output terminal, a third and fourth transistor with gates coupled to the other output terminal, a fifth and sixth transistor with gates coupled to respective output terminal of the local oscillator driver, the sources of the first and third transistors coupled to the drain of the fifth transistor, the sources of the second and fourth transistor coupled to the drain of the sixth transistor, the sources of the fifth and sixth transistor coupled to ground, the drains of the first and fourth transistor coupled to one output terminal of a mixer output port, and the drains of the second and third transistor coupled to the other output terminal of the mixer output port.
    Type: Grant
    Filed: June 20, 2005
    Date of Patent: May 27, 2008
    Assignee: Infineon Technologies AG
    Inventors: Andrej Litwin, Ganesh Kathiresan
  • Patent number: 7375582
    Abstract: Polyphase filters comprise a plurality of filters each filter having passive elements. The filters are provided with integrators comprising amplifiers with admittance elements in feedback paths to create one or more other poles not situated on the negative imaginary axis in the plane-zero plot. A conductance element couples an output of an integrator of the integrators to an input of a previous integrator for introducing a frequency shift for at least one pole in the plane pole-zero plot. A capacitor couples an output of the integrator to an input of a next integrator for improving the quality factor of the polyphase filter. A signal inversion allows conductance elements to have negative values necessary for locating at least one pole at the most optimal location in the plane pole-zero plot.
    Type: Grant
    Filed: March 20, 2003
    Date of Patent: May 20, 2008
    Assignee: NXP B.V.
    Inventor: Eduard Ferdinand Stikvoort
  • Patent number: 7373113
    Abstract: A reference frequency generation method and apparatus for communication systems that transmit and receive data by use of an ultra wide band of at least two frequency groups having at least two reference frequencies. The method and apparatus generate the reference frequencies by generating generation frequencies by use of a frequency generated from the local oscillator, and generating adjustment frequencies for adjusting the generation frequency. One generation frequency and one adjustment frequency are selected from the generation frequencies and adjustment frequencies, and the reference frequencies are generated by use of the selected generation frequency and adjustment frequency.
    Type: Grant
    Filed: November 2, 2004
    Date of Patent: May 13, 2008
    Assignees: Samsung Electronics Co., Ltd., Staccato Communications, Inc.
    Inventors: Woo-Kyung Lee, Wan-jin Kim
  • Patent number: 7369829
    Abstract: A signal reception apparatus and method for communication systems. The signal reception apparatus for communication systems according to the present invention is applicable to communication environments in which a plurality of sub-bands having different frequency bands are sequentially used for communications. An embodiment of the invention has a multi-band index generation unit, a multi-band frequency generation unit, a multiplication unit, a correlation signal reception unit, and a buffer unit. The multi-band index generation unit generates a multi-band index corresponding to a sub-band to which a received signal is transmitted in correspondence with the multi-band index. The multiplication unit outputs a signal obtained by multiplying the received signal by the multi-band frequency. The correlation signal reception unit integrates and outputs the signal of the multiplication unit based on an integral time set in correspondence with the multi-band index.
    Type: Grant
    Filed: August 11, 2004
    Date of Patent: May 6, 2008
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Ye-hoon Lee, Seung-young Park, Yong-suk Kim, Wan-jin Kim, Woo-kyung Lee
  • Patent number: 7366478
    Abstract: Radio-frequency (RF) apparatus includes receiver analog circuitry that receives an RF signal and provides at least one digital signal to receiver digital circuitry that functions in cooperation with the receiver analog circuitry. The receiver analog circuitry and the receiver digital circuitry are partitioned so that interference effects between the receiver analog circuitry and the receiver digital circuitry tend to be reduced.
    Type: Grant
    Filed: June 28, 2004
    Date of Patent: April 29, 2008
    Assignee: Silicon Laboratories Inc.
    Inventors: Donald A. Kerth, Richard T. Behrens, Jeffrey W. Scott, G. Diwakar Vishakhadatta, G. Tyson Tuttle, Vishnu Shankar Srinivasan
  • Patent number: 7366485
    Abstract: The circuits of a multimode wireless transmitter are complex and large, and thus difficult to incorporate in a portable wireless device. This problem is solved for a multimode wireless transmitter by enabling the first frequency mode circuit and the second frequency mode circuit to use the same frequency dividers.
    Type: Grant
    Filed: March 2, 2005
    Date of Patent: April 29, 2008
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventor: Atsushi Yoshimoto
  • Patent number: 7363018
    Abstract: Described are a method and a device for high speed transmission of a data signal across an electrical interconnect in an integrated circuit. An optical carrier is modulated with a local oscillator signal at a modulation frequency substantially greater than the data signal to generate an optical local oscillator signal. Phototransducers at the ends of the interconnect illuminated by the optical local oscillator signal generate electrical local oscillator signals. At the transmit end of the interconnect, the data signal is mixed with an electrical local oscillator signal to generate an upconverted data signal. After transmission across the interconnect to the receive end, the upconverted data signal is mixed with the electrical local oscillator signal to retrieve the original data signal.
    Type: Grant
    Filed: January 18, 2005
    Date of Patent: April 22, 2008
    Assignee: Massachusetts Institute of Technology
    Inventors: Brian Tyrrell, Robert Reich
  • Publication number: 20080081589
    Abstract: A system for generating a tuning voltage including a processor, a tank circuit, and a feedback loop. The processor creates a tuning voltage that is provided to the tank circuit. A feedback loop optimizes tuning performance by adjusting the tuning voltage based on radio signal strength.
    Type: Application
    Filed: September 29, 2006
    Publication date: April 3, 2008
    Inventors: Yao H. Kuo, Thomas Wharam
  • Patent number: 7353008
    Abstract: A Method and System for Optimizing Decibel Data Conversion. This invention provides an ability to convert linear signals into decibel units via digital logic circuitry. The resultant system can present information to users in real-time. This is made possible by performing an approximation function that is simple enough to be implemented directly in digital hardware, rather than through software executed by massive computing resources. An exemplary application for this technology is as a component of a surgical reactive electronic jamming system. This invention allows a surgical reactive jammer to determine precisely the correct jamming thresholds to apply in real-time. It allows signal surveillance equipment to survey the spectrum and display those results in dBm with far more efficiency than before. Finally, it enables a whole industry of communications related devices that need to do real time decibel conversion.
    Type: Grant
    Filed: May 1, 2006
    Date of Patent: April 1, 2008
    Assignee: Agilent Technologies, Inc.
    Inventor: Lars Karlsson
  • Publication number: 20080076375
    Abstract: A technique includes providing a plurality of local oscillator signals such that each of the local oscillator signals has a different phase. The technique includes providing scaling units to scale the input signal pursuant to different scaling factors to generate scaled input signals. The scaling factors are selected on a periodic function of the phases. The technique also includes providing mixing circuits to mix the local oscillator signals with the scaled input signals to generate mixed signals and providing an adder to combine the mixed signals to generate an output signal.
    Type: Application
    Filed: September 27, 2006
    Publication date: March 27, 2008
    Inventors: Daniel J. Cooley, Aslamali A. Rafi
  • Publication number: 20080076376
    Abstract: Embodiments of the present invention provide a method and a system for removing a Radio Frequency (RF) Direct Current (DC) offset in a signal. The method includes: subtracting a canceling DC from a signal carrying an RF DC offset and generating an RF DC offset residual; outputting the signal when the RF DC offset residual in the signal is zero; adjusting the canceling DC according to the RF DC offset residual in the signal if the RF DC offset residual is not zero. The system includes a receiver, an RF DC offset canceling unit, a determining unit, a canceling DC adjusting unit, and an output unit. With embodiments of the present invention, the RF DC offset in the signal may be effectively removed.
    Type: Application
    Filed: August 30, 2007
    Publication date: March 27, 2008
    Applicant: HUAWEI TECHNOLOGIES CO., LTD.
    Inventors: Jing Yang, Yu Liu, Gengshi Wu
  • Patent number: 7349676
    Abstract: An upconverter receives an intermediate frequency (IF) modulated signal on a port (5) and a local oscillator carrier signal at a port (6). A comb generator (13-15) generates a comb-like waveform from the carrier signal, the waveform having a peak for each of a number of multiples of the carrier fundamental. A bandpass filter (16) selects one of the comb peaks and there is further multiplication at a quadrupler (20). The modulated signal (IF) and the multiplied carrier are mixed in a mixer (23) to provide a high frequency upper sideband (LO+IF) output. The output is transmitted in a waveguide (7) which is integral with the casing (2, 3) and which performs high frequency filtering by virtue of its shape.
    Type: Grant
    Filed: September 24, 2004
    Date of Patent: March 25, 2008
    Assignee: Farran Technology Limited
    Inventors: Sean Cremin, Jason Lynch, Brendan Lyons
  • Patent number: 7349673
    Abstract: An exemplary embodiment of the present invention described and shown in the specification and drawings is a transceiver with a receiver, a transmitter, a local oscillator (LO) generator, a controller, and a self-testing unit. All of these components can be packaged for integration into a single IC including components such as filters and inductors. The controller for adaptive programming and calibration of the receiver, transmitter and LO generator. The self-testing unit generates is used to determine the gain, frequency characteristics, selectivity, noise floor, and distortion behavior of the receiver, transmitter and LO generator. It is emphasized that this abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or the meaning of the claims.
    Type: Grant
    Filed: January 31, 2006
    Date of Patent: March 25, 2008
    Assignee: Broadcom Corporation
    Inventors: Shervin Moloudi, Ahmadreza Rofougaran, Maryam Rofougaran