Class / Patent application number | Description | Number of patent applications / Date published |
455208000 | With synchronized or controlled local oscillator | 38 |
20080254756 | Receiver and Wireless Communication Apparatus - A receiver has a first voltage control oscillator configured to generate a first oscillation signal, a second voltage control oscillator configured to generate a second oscillation signal having a first phase, a first phase comparator configured to detect a phase difference between the first and second oscillation signals, a demodulator configured to perform demodulation processing of the received signal and to generate timing information of a second phase included in the first oscillation signal, a second phase comparator configured to detect the phase difference between the first and second oscillation signals, and a first control voltage generator configured to generate a first control voltage for controlling a phase and a frequency of the second voltage control oscillator based on the phase difference detected by the second phase comparator. | 10-16-2008 |
20090004985 | Signal Processing Apparatus - In a PLL circuit, an oscillation frequency is quickly and accurately locked to a target frequency. There is provided a PLL circuit including a VCO ( | 01-01-2009 |
20090029663 | Frequency Source Synchronization And Redundancy - A system and method for ensuring proper synchronization of a plurality of frequency sources used in reception diversity-based radio reception. The frequency sources are concatenated in a synchronization loop, through which one frequency source having a high performance oscillator is configured as a master source. Through its oscillator, the master provides an internal synchronization signal that synchronizes all other sources, which have lower performance oscillators and are configured as slaves. Upon a failure in the master oscillator or in the synchronization loop, a slave source takes over as an alternative master source and provides its internal oscillator signal as an alternative synchronization signal to all other frequency sources. | 01-29-2009 |
20090111409 | DYNAMIC BIASING OF A VCO IN A PHASE-LOCKED LOOP - A local oscillator includes a phase-locked loop. The phase-locked loop includes voltage controlled oscillator (VCO) and a novel VCO control circuit. The VCO control circuit may be programmable and configurable. In one example, an instruction is received onto the VCO control circuit to change the power state of the VCO. The instruction is issued by other circuitry in response to a detected change in RF channel conditions (for example, a change in a signal-to-noise determination) in a cellular telephone. In response, the VCO control circuit outputs control signals that gradually widen the loop bandwidth of the PLL, then gradually change the VCO bias current to change the VCO power state, and then narrow the loop bandwidth of the PLL back to its original bandwidth. The entire process of widening the PLL bandwidth, changing the VCO power state, and narrowing the PLL bandwidth occurs while the PLL remains locked. | 04-30-2009 |
20090215417 | RECEIVER FOR AMPLITUDE-MODULATED SIGNALS - In a receiver, a synchronization circuit (MIX | 08-27-2009 |
20100041357 | METHOD AND APPARATUS FOR AUTOMATIC FREQUENCY CORRECTION - A method and apparatus for automatic frequency correction in a demodulation circuit. The apparatus includes a demodulator, a frequency offset estimator, a frequency controller, and an oscillator. The oscillator provides a receiver clock signal which the demodulator employs to demodulate a modulated signal. The frequency offset estimator estimates an offset between a carrier wave frequency of the modulated signal and a frequency of the receiver clock signal. The frequency controller provides a frequency control signal to the oscillator for adjusting the frequency of the receiver clock. While the estimated offset is outside of an adjustment range, the frequency controller maintains the frequency control signal at its previous value. The frequency controller also adjusts the adjustment range based on past error signal values. | 02-18-2010 |
20100120389 | Replica DLL for Phase Resetting - A method, algorithm, architecture, circuits, and/or systems for using a delay-locked loop (DLL) for phase adjustment in a direct conversion radio receiver are disclosed. The DLL is configured to avoid a perceived phase shift when the control voltage to a delay line is reset upon reaching a predetermined amount. Embodiments disclosed include a DLL, a radio receiver using the DLL, a circuit for resetting the DLL, a method for recovering a modulated radio signal, and a method of synchronizing a reference clock to a radio signal. The approach can allow for improved synchronization of the reference clock to a received radio signal during baseband frequency recovery. | 05-13-2010 |
20100120390 | LO GENERATION WITH DESKEWED INPUT OSCILLATOR SIGNAL - Techniques for generating local oscillator (LO) signals are described. In one design, an apparatus may include a deskew circuit and a divider circuit. The deskew circuit may receive a differential input oscillator signal having timing skew and provide a differential output oscillator signal having reduced timing skew. The differential input oscillator signal may include first and second input oscillator signals, and the differential output oscillator signal may include first and second output oscillator signals. In one design, the deskew circuit may include first and second variable delay circuits that receive the first and second input oscillator signals, respectively, and provide the first and second output oscillator signals, respectively. Each output oscillator signal may have an adjustable delay selected to reduce timing skew. The divider circuit may divide the differential output oscillator signal in frequency and provide differential I and Q divided signals, which may be used to generate LO signals. | 05-13-2010 |
20100248666 | METHOD AND DEVICE FOR SYNCHRONIZATION AND CHANNEL ESTIMATION IN A RADIO RECEIVER - A device and method in a radio receiver for generating synchronization and channel estimation information based on three parameters consisting of a synchronization position, at least one whitening filter parameter, and a channel estimate. A spatially and temporally stacked signal model is generated by stacking successive samples of temporally adjacent received signal vectors and corresponding training vectors. Initial estimates of a first one or two of the three parameters are then generated based on the spatially and temporally stacked signal model. The rest of the three parameters are then computed based on the initial estimates of the first one or two parameters. If a stopping criterion is met, the method ends and the parameters are used to process the signal. If the stopping criterion is not met, additional iterations are performed to improve the synchronization and estimation information. | 09-30-2010 |
20100273442 | JAMMER DETECTION BASED ADAPTIVE PLL BANDWIDTH ADJUSTMENT IN FM RECEIVER - A frequency synthesizer within an FM receiver employs a Phase-Locked Loop (PLL) to generate a Local Oscillator (LO) signal. The LO signal is supplied to a mixer. The FM receiver also includes jammer detection functionality. If no jammer is detected, then the loop bandwidth of the PLL is set to have a relatively high value, thereby favoring suppression of in-band residual FM. If a jammer is detected, then the loop bandwidth of the PLL is set to have a relatively low value, thereby favoring suppression of out-of-band SSB phase noise. By adaptively changing loop bandwidth depending on whether a jammer is detected, performance requirements on sub-circuits within the PLL can be relaxed while still satisfying in-band residual FM and out-of-band SSB phase noise requirements. By allowing the VCO of the PLL to generate more phase noise due to the adaptive changing of loop bandwidth, VCO power consumption can be reduced. | 10-28-2010 |
20100285764 | FREQUENCY MODULATION RECEIVER AND RECEIVING METHOD THEREOF - A frequency modulation receiver is provided. The frequency modulation receiver includes an automatic frequency controller and a signal detector. The automatic frequency controller receives a demodulated frequency modulation signal demodulated from a radio frequency signal and outputs a control voltage to control an oscillation frequency of a local oscillator. The signal detector coupled to the automatic frequency controller receives the control voltage and determines whether the radio frequency signal is a frequency modulation signal according to the control voltage and a predetermined voltage range. | 11-11-2010 |
20110053537 | FREQUENCY MODULATION RECEIVER WITH A LOW POWER FREQUENCY SYNTHESIZER - A frequency modulation (FM) receiver with a low power frequency synthesizer. A FM receiver includes a low noise amplifier for processing a received input signal, a frequency synthesizer having an oscillator for generating a local oscillator signal by supplying a bias current to the oscillator, and a mixer for generating an intermediate frequency signal by mixing the received input signal with the local oscillator signal. The FM receiver further includes an analog to digital converter for converting the intermediate frequency signal to a digital signal and a bias current control module for measuring a signal strength of the received input signal based on the digital signal and for controlling the bias current. | 03-03-2011 |
20110070854 | ASYNCHRONOUS FIRST IN FIRST OUT INTERFACE, METHOD THEREOF AND INTEGRATED RECEIVER - An asynchronous FIFO interface having a readout clock asynchronous with a write clock is provided. The asynchronous FIFO interface includes a FIFO buffer, a clock controller, a reference source and a signal source. The FIFO buffer receives a digital signal from an ADC according to the write clock and outputs a digital signal to a processor according to the readout clock. The clock controller outputs a clock control signal according to the amount of data stored in the FIFO buffer. The reference source provides an oscillation frequency. The signal source divides the oscillation frequency by a first integer divisor to generate a reference frequency, divides the readout clock by a second integer divisor to generate an input frequency, and outputs a control signal by comparing the reference frequency with the input frequency. | 03-24-2011 |
20110230155 | MILLIMETER WAVE OSCILLATOR - An oscillator is described, comprising at least one transistor having a first terminal connected to a power supply voltage. The oscillator comprises at least one inductive element connected to a second terminal of the transistor and to a bias voltage and at least one capacitive element coupled between a third terminal of the transistor and ground. The oscillator further comprises means to collect the output signal of said oscillator on the second terminal of the transistor. The oscillator is of the millimeter wave type, i.e., both the inductive element and the capacitive element are sized such that the oscillation frequency is between 30 and 300 gigahertz. | 09-22-2011 |
20120270515 | DEMODULATOR OF A FREQUENCY-MODULATED ELECTRICAL SIGNAL - A demodulator of an FM signal modulated about a carrier frequency with a modulation frequency has an RF oscillator configured to be synchronized, under identical conditions of operation, with oscillations at first and second frequencies used in the FM signal to encode respective pieces of information. The oscillator has a magnetoresistive device; and a low-pass filter connected to an output electrode of the magnetoresistive device to filter an oscillating signal, generated by the oscillator and to a rendering terminal to provide, as a demodulated electrical signal, the filtered signal, the cut-off frequency f | 10-25-2012 |
20130078936 | RECEIVER HAVING A CALIBRATION SOURCE - An RF receiver includes an RF signal reception path to process an input signal for the receiver for a first mode of the receiver; an oscillator; and a harmonic generator. The harmonic generator generates a harmonic signal in response to operation of the oscillator to replace the input signal with the harmonic signal for a second mode of the receiver. | 03-28-2013 |
20130165066 | UNIDIRECTIONAL SAMPLING MIXER - A unidirectional sampling mixer utilizes a stepped phase modulation to shift the frequency of an RF input signal supplied to an RF input switch. An ordered set of phase shift values to be applied to the RF input signal and a set of times each element of which corresponds to a time at which a phase shift value is be applied to the RF signal are determined. For each phase shift value, a controller controls the RF input switch to select an input of a phase shifting device and controls an RF output switch to select an output of the phasing shifting device. The input and the output of the phase shifting device are selected to apply the phase shift value at its corresponding time to the RF input signal. A frequency shifted signal is supplied to an RF output port from an output of the RF output switch. | 06-27-2013 |
20130316668 | LOW NOISE AMPLIFIERS WITH TRANSFORMER-BASED SIGNAL SPLITTING FOR CARRIER AGGREGATION - Low noise amplifiers (LNAs) supporting carrier aggregation are disclosed. In an exemplary design, an apparatus (e.g., a wireless device, an integrated circuit, etc.) includes an amplifier circuit, a transformer, and a plurality of downconverters. The amplifier circuit receives and amplifies an input radio frequency (RF) signal and provides an amplified RF signal. The input RF signal includes transmissions sent on multiple carriers at different frequencies to a wireless device. The transformer includes a primary coil coupled to the amplifier circuit and a plurality of secondary coils providing a plurality of output RF signals. The plurality of downconverters downconvert the plurality of output RF signals with a plurality of local oscillator (LO) signals at different frequencies. Each downconverter includes a pair of mixers that receives one output RF signal and one LO signal and provides inphase and quadrature downconverted signals for one set of carriers being received. | 11-28-2013 |
20130316669 | LOW NOISE AMPLIFIERS WITH CASCODE DIVERT SWITCH FOR CARRIER AGGREGATION - Low noise amplifiers (LNAs) supporting carrier aggregation are disclosed. In an exemplary design, an apparatus (e.g., a wireless device, an integrated circuit, etc.) includes first and second amplifier circuits and a divert cascode transistor. Each amplifier circuit may include a gain transistor and a cascode transistor. The divert cascode transistor is coupled between the output of the first amplifier circuit and the gain transistor in the second amplifier circuit. The first and second amplifier circuits receive an input radio frequency (RF) signal including transmissions sent on multiple carriers at different frequencies to a wireless device. The first and second amplifier circuits and the divert cascode transistor are controlled to amplify the input RF signal and provide (i) one amplified RF signal for one set of carriers in a first operating mode or (ii) two amplified RF signals for two sets of carriers in a second operating mode. | 11-28-2013 |
20130324061 | ELECTRICALLY SMALL, SUPER DIRECTIVE ANTENNAS - An electrically small receiver system is provided. The receiver system includes a plurality of antennas and a signal processing circuit. The plurality of antennas includes a first antenna configured to receive a first signal and a second antenna configured to receive a second signal. The signal processing circuit includes a phase shifter configured to apply a phase shift to the received second signal. The phase shift applied by the phase shifter is a function of an angle of incidence of the second signal measured relative to a boresight direction of the plurality of antennas. The signal processing circuit is configured to form an output signal that is a combination of the received first signal and the phase shifted second signal. | 12-05-2013 |
20140302806 | UNIDIRECTIONAL SAMPLING MIXER - A unidirectional sampling mixer utilizes a stepped phase modulation to shift the frequency of an input signal. An RF input signal is supplied to an RF input switch from an RF input port. An ordered set of phase shift values to be applied to the RF input signal and a set of times each element of which correspond to a time at which a phase shift value is be applied to the RF signal are determined. For each phase shift value within the ordered set of phase shift values, a controller controls the RF input switch to select an input of a phase shifting device and controls an RF output switch to select an output of the phasing shifting device. The input of the phase shifting device and the output of the phase shifting device are selected to apply the phase shift value at its corresponding time to the RF input signal. A frequency shifted signal is supplied to an RF output port from an output of the RF output switch. This Abstract is not to be considered limiting, since other embodiments may deviate from the features described in this Abstract. | 10-09-2014 |
20140323073 | DISTRIBUTED LOCAL OSCILLATOR GENERATION AND SYNCHRONIZATION - Methods, systems, computer-readable media, and apparatuses for locally generating and synchronizing oscillation signals in a phased array system are presented. Multiple sub-array modules are used for collectively transmitting any number of beams on carrier frequencies, wherein each of the sub-array modules includes a transmit antenna, an oscillator configured to generate an oscillation signal, and a control element configured to phase lock the oscillation signal with other oscillation signals used in the system. The control element determines a phase difference measure that represents an average difference in phase between the oscillation signal and other oscillation signals used in the system, generates an average error signal, wherein the average error signal represents the phase difference measure, obtains information regarding oscillator trim signals applied with respect to the other oscillation signals generated in the system, and adjusts a frequency of the oscillation signal using the generated local oscillator trim signal. | 10-30-2014 |
20150333815 | MULTI-WAY DIVERSITY RECEIVER WITH MULTIPLE SYNTHESIZERS IN A CARRIER AGGREGATION TRANSCEIVER - Certain aspects of the present disclosure provide multi-way diversity receivers with multiple synthesizers. Such a multi-way diversity receiver may be implemented in a carrier aggregation (CA) transceiver. One example wireless reception diversity circuit generally includes three or more receive paths for processing received signals and two or more frequency synthesizing circuits configured to generate local oscillating signals to downconvert the received signals. Each of the frequency synthesizing circuits is shared by at most two of the receive paths, and each pair of the frequency synthesizing circuits may generate a pair of local oscillating signals having the same frequency. | 11-19-2015 |
20150381214 | DIGITAL-TO-TIME CONVERTER SPUR REDUCTION - This application discusses, among other things, apparatus and methods for improving spurious frequency performance of digital-to-time converters (DTCs). In an example, a method can include receiving a code at selection logic of a digital-to-time converter at a first instant, selecting a first delay path of the DTC to provide a delay associated with the code, associating a second delay path with the code, receiving the code at the selection logic at a second instant, and selecting the second delay path of the DTC to provide the delay associated with the code. | 12-31-2015 |
20160073369 | SYNCHRONIZATION SYSTEM AND METHOD FOR ACHIEVING LOW POWER BATTERY OPERATION OF A VEHICLE LOCATING UNIT IN A STOLEN VEHICLE RECOVERY SYSTEM WHICH RECEIVES PERIODIC TRANSMISSIONS - Synchronization for achieving low power battery operation of a vehicle locating unit in a stolen vehicle recovery system whose radio receiver receives periodic transmissions, includes receiving periodic transmissions; turning on a radio receiver for a limited time to detect an expected message; if an expected message is not found, turning off the receiver and turning it on again after a time asynchronous with the transmission period; and after finding an expected message, waiting for the period of the transmissions less the length of an expected message and then looking for a synchronization symbol in the expected message and synchronizing subsequent actuation of the receiver using that synchronization symbol. | 03-10-2016 |
455209000 | Plural local oscillators or mixers | 13 |
20090081976 | RECEIVER AND ELECTRONIC APPARATUS USING THE SAME - A receiver has a first semiconductor chip and second semiconductor chip for receiving signals of a first radio frequency band, and a communication unit for performing communication using signals of a second radio frequency band. A second mixing unit in the second semiconductor chip uses second local signals supplied from a second local signal oscillator when the frequency of first local signals fed from a first-local-signal-output terminal to a first-local-signal-input terminal is within a predetermined range from the second frequency band, or uses first local signals supplied from the first-local-signal-input terminal when the frequency of the first local signals fed from the first-local-signal-output terminal to the first-local-signal-input terminal is out of the predetermined range from the second frequency band. | 03-26-2009 |
20090088110 | RADIO FREQUENCY RECEIVER ARCHITECTURE - A radio frequency receiver includes a passive mixer configured to receive and RF signal and a low input impedance circuit configured to receive the output of the passive mixer. | 04-02-2009 |
20100029234 | MIXER CELL WITH A DYNAMIC BLEED CIRCUIT - A mixer is described having a Gilbert cell structure including a first input and a second input for inputting an RF signal, a third input and a fourth input for inputting a local oscillator signal, a first output and a second output for outputting an IF signal, a plurality of switches for converting the RF signal to an IF signal, and a dynamic bleed circuit for dynamically reducing the dc-current of the switches at the switching-point. As the dc-current of the switches is reduced at the point of commutation, the 1/f-noise is also strongly reduced without degrading the linearity. The switching happens at twice the local oscillator frequency. The mixer also includes a common mode feedback circuit that feeds the common mode signal, optionally amplified, to a common mode feedback control device that is in series between the dynamic bleed circuit and the supply voltage. | 02-04-2010 |
20100105344 | METHOD AND APPARATUS FOR BIASING A MIXER - A method and apparatus for mixing an input signal in a communications system. The apparatus includes an in-phase mixer, a quadrature mixer, and bias circuits. The in-phase mixer mixes the input signal with an in-phase local oscillator signal. The quadrature mixer mixes the input signal with a quadrature local oscillator signal. The quadrature local oscillator signal is approximately 90° out of phase with the in-phase local oscillator signal. The bias circuits provide DC bias to the in-phase mixer and to the quadrature mixer to balance their outputs. | 04-29-2010 |
20100178890 | RECEIVING DEVICE AND ELECTRONIC EQUIPMENT USING THE SAME - In an image rejection mixer, when a signal in the first radio frequency band is inputted to an input terminal, the first mixer and the second mixer convert the input signal in the first radio frequency band to a signal in the first intermediate frequency band by using the first local signal from a local signal oscillator, and a filter circuit attenuates an image interfering signal existing in the first intermediate frequency band by means of the first attenuation band. Also, when a signal in the second radio frequency band is inputted to the input terminal, the first mixer and the second mixer convert the input signal in the second radio frequency band to a signal in the second intermediate frequency band by using the second local signal from the local signal oscillator, and the filter circuit attenuates an image interfering signal existing in the second intermediate frequency band by means of the second attenuation band that is narrower than the first attenuation band. | 07-15-2010 |
20100233981 | Method and circuit for operating a mixer - A mixer for mixing a received signal and a local oscillator signal is provided. The local oscillator signal is modulated by means of a modulation signal and the modulated local oscillator signal is injected into the received signal. | 09-16-2010 |
20110003569 | Frequency Translated Filters For Wideband Applications - Embodiments of a SAW-less RF receiver front-end that includes a frequency translated notch filter (FTNF) are presented. An FTNF includes a passive mixer and a baseband impedance. The baseband impedance includes capacitors that form a low-Q band-stop filter. The passive mixer is configured to translate the baseband impedance to a higher frequency. The translated baseband impedance forms a high-Q notch filter and is presented at the input of the FTNF. The FTNF can be fully integrated in CMOS IC technology (or others, e.g., Bipolar, BiCMOS, and SiGe) and applied in wireless receiver systems including EDGE/GSM, Wideband Code Division Multiple Access (WCDMA), Bluetooth, and wireless LANs (e.g., IEEE 802.11). In addition, embodiments of a generalized FTNF for wideband applications are presented. | 01-06-2011 |
20110086604 | RF SIGNAL RECEIVING APPARATUS - An RF signal receiving apparatus includes a first poly-phase filter, a second poly-phase filter, a first frequency-mixer module, a switch and a low-pass filter module. The first poly-phase filter receives an RF input signal and produces a filtered RF signal according to the received RF input signal. The first frequency-mixer module conducts frequency-mixing operation on a reduced-frequency signal and the filtered RF signal to produce a plurality of reduced-frequency RF signals. The switch receives and transmits the reduced-frequency RF input signal to a first channel or a second channel according to a selection signal. The second poly-phase filter receives the reduced-frequency RF signal transmitted by the second channel and filters the received signal. The low-pass filter module receives the filtered reduced-frequency RF signal or the reduced-frequency RF signal transmitted by the first channel to conduct low-pass filtering operation and produces a low-intermediate-frequency signal or a zero-intermediate-frequency signal. | 04-14-2011 |
20120015616 | ADAPTIVE IIP2 CALIBRATION - A radio frequency transceiver ( | 01-19-2012 |
20120046007 | Rotating Harmonic Rejection Mixer - In one embodiment, the present invention includes a mixer circuit to receive and generate a mixed signal from a radio frequency (RF) signal and a master clock signal, a switch stage coupled to an output of the mixer circuit to rotatingly switch the mixed signal to multiple gain stages coupled to the switch stage, and a combiner to combine an output of the gain stages. | 02-23-2012 |
20130183918 | WIRELESS COMMUNICATION DEVICE AND CONTROL METHOD FOR WIRELESS COMMUNICATION DEVICE - An antenna receives an RF signal and an RF signal at different frequency bands. An oscillator outputs a local oscillator signal at a frequency f | 07-18-2013 |
20140080433 | Receiver and Receiving Method of Receiver - Embodiments of the present invention provide a receiver and a receiving method of the receiver, so that monolithic integration of multiple receiving channels can be implemented. The receiver includes: a zero intermediate frequency channel, performing in-phase/quadrature (IQ) down conversion on a radio frequency signal at a first frequency band using a frequency division or frequency multiplication signal of a first oscillation signal; and a superheterodyne channel, performing down conversion on a radio frequency signal at a second frequency band using the frequency division or frequency multiplication signal of the first oscillation signal, where the first frequency band is different from the second frequency band. According to the embodiments of the present invention, a zero intermediate frequency channel and a superheterodyne channel use a same oscillation signal or a same frequency division or frequency multiplication signal of the oscillation signal, thereby monolithic integration of multiple receiving channels can be implemented. | 03-20-2014 |
20140378078 | Conversion Circuit For Converting Complex Analog Signal Into Digital Representation - A conversion circuit for converting a complex analog input signal having an in-phase (I) component and a quadrature-phase (Q) component is disclosed. It comprises a channel-selection filter configured to filter the complex analog input signal, thereby generating a channel-filtered I and Q components, and one or more processing circuits. Each processing circuit comprises four mixers for generating a first and a second frequency-translated I component, and a first and a second channel-filtered Q component based on two LO signals with equal LO frequency and a 90° mutual phase shift. Each processing circuit also comprises a combiner circuit for generating a first, a second, a third, and a fourth combined signal proportional to sums and differences between the frequency translated I and Q components. The first and the fourth combined signals form a first complex signal, and the second and the third combined signals form a second complex signal. | 12-25-2014 |