Abstract: A method is described in particular for reducing interference due to phase noise in a radar system, in which in a first noncoherent transceiver unit (NKSE1) a first signal (sigTX1) is generated and transmitted, in particular emitted, via a path (SP), in a further, in particular second noncoherent transceiver unit (NKSE2), a first signal (sigTX2) is generated and transmitted, in particular emitted, via the path (SP), the signals (sigTX1 and sigTX2) are received directly or indirectly in the respective other transceiver unit and are processed further therein as received signals sigRX12 and sigRX21, in the first transceiver unit (NKSE1), a comparison signal (sigC12) is formed from its first signal (sigTX1) and from such a first signal (sigRTX2) received from the further transceiver unit (NKSE2) via the path (SP), and in the further transceiver unit (NKSE2), a further comparison signal (sigC21) is formed from its first signal (sigTX2) and from such a first signal (sigTX1) received from the first transceiver unit

Abstract: A radar system (200, 200a) and a method of operating a radar system are described, the radar system (200, 200a) comprising: a plurality of ICs (210, 220), each IC (210, 220) comprising: a respective LO output (212, 222) for selectively outputting a respective LO signal, and a respective LO input (214, 224); and a coupling device (230, 330), the coupling device (230, 330) comprising: a plurality of inputs (232, 234; 341, 342, 351, 352), each input being coupled to the LO output (212, 222) of a respective IC (200, 200a), and a plurality of outputs (236, 238; 363, 364, 373, 374), each output being coupled to the LO input (212, 222) of a respective IC (214, 224); wherein the coupling device (230, 330) is configured such that a LO signal arriving at any one of said plurality of inputs (232, 234; 341, 342, 351, 352) is distributed to each of said plurality of outputs (236, 238; 363, 364, 373, 374). The coupling device (230, 330) may comprise at least one directional coupler.

Abstract: Radio frequency (RF) communication systems with coexistence management are provided herein. In certain embodiments, a mobile device includes a first antenna, a first front end system that receives an RF receive signal from the first antenna, a first transceiver coupled to the first front end system, a second antenna, a second front end system that provides an RF transmit signal to the second antenna, and a second transceiver coupled to the second front end system. The second front end system observes the RF transmit signal to generate an RF observation signal, which is downconverted and processed by the second transceiver to generate digital observation data that is provided to the first transceiver. The first transceiver downconverts the RF receive signal to baseband, and compensates the baseband receive signal for an amount of RF signal leakage indicated by the digital observation data.

Abstract: A local oscillator generation system includes a first frequency divider configured to divide frequencies of a first voltage controlled oscillator signal and a second voltage controlled oscillator signal by 2, and output a first divided signal and a second divided signal; a mixer configured to mix the first voltage controlled oscillator signal, the second voltage controlled oscillator signal, the first divided signal, and the second divided signal, and output a first frequency mixed signal and a second frequency mixed signal; a transimpedance amplifier configured to amplify the first frequency mixed signal and the second frequency mixed signal, and output a first amplified signal and a second amplified signal; and a band-pass filter configured to filter the first amplified signal and the second amplified signal, and output a first filtered signal and a second amplified signal.

Abstract: A method and apparatus are disclosed for a configurable mixer capable of operating in a linear, a legacy, and a low-power mode. In the linear mode, the configurable mixer is configured to operate as a double-balanced mixer to multiply a first differential signal by a second differential signal. In the legacy mode, the configurable mixer is configured to as a double-balanced mixer to multiply a differential signal by a single-ended signal. In the low-power mode, the configurable mixer is configured to operate as a single-balanced mixer to multiply a differential signal by a single-ended signal. The operating mode of the configurable mixer may be based, at least in part, on a mode control signal. In some embodiments, the configurable mixer may be included in an analog front end of a wireless communication device.

Abstract: A technique includes using a first oscillator to clock operations of a radio of an integrated circuit (IC). The technique includes intermittently using the first oscillator to frequency tune a second oscillator of the IC.

Abstract: The present disclosure illustrates a multi-systems integrated modulation module. The modulation module includes a first modulation circuit and a second modulation circuit. The first modulation circuit includes a high frequency oscillator and high frequency mixers. The second modulation circuit includes a low frequency oscillator and low frequency mixers. The second modulation circuit couples to the first modulation circuit. The high frequency mixers couple to the high frequency oscillator and the low frequency mixers couple to the low frequency oscillator. The high frequency mixers and the low frequency mixers provide high frequency signals and low frequency signals separately. The frequency mixers mix radio frequency signals with the high frequency signals or low frequency signals. The modulation module forms a first signal path by the first modulation circuit, and forms a second signal path by the first modulation circuit and the second modulation circuit.

Abstract: Signal processing methods and apparatus are disclosed, including a method of receiving a signal using at least first and second antennas, the method comprising obtaining a first signal comprising a component of the received signal received at said first antenna, obtaining a second signal comprising a component of the received signal received at said second antenna, wherein the first and second signals comprise at least partially orthogonal components of the received signal, performing operations on said first signal and said second signal to obtain first and second modified signals, wherein the operations substantially maximise a level of the received signal in the first modified signal and substantially minimise a level of the received signal in the second modified signal, and processing the first modified signal.

Abstract: Embodiments of the present disclosure use shared oscillator for cellular communications and location detection in a communication device. The communications device estimates a frequency offset of one of its subsystems. The communications device determines a frequency offset that results from drifting of this shared oscillator, typically caused by aging and/or changes in temperature, voltage, humidity, pressure, and/or vibration to provide some examples, from the frequency offset this subsystem. The communications device provides various compensation parameters to its various subsystems to compensate for the frequency offset that results from drifting of the oscillator.

Abstract: Methods and apparatuses for concurrently recording multiple radio channels. A recorder includes a wideband tuner having a complex mixer for converting a received wideband RF signal to a complex signal that is then digitized. A digital front end module applies a number of complex down-mixers to the digital complex signal to generate the multiple radio channels in the baseband. Each one of the multiple radio channels in the baseband is further filtered, decimated and demodulated. A digital signal processing unit encodes each demodulated channel according to an audio compression format and stores the then encoded audio content to a storage unit. An RBDS decoder parses radio data service information associated with the stored audio content. The radio data service information is stored in a first section of the storage unit while the encoded audio content is stored in a second section of the storage unit.

Abstract: A receiver having a mixer for mixing a radio frequency signal and a local oscillator signal so as to generate a base band signal, a detecting unit for generating from the base band signal a detection signal that represents an extent of local oscillation leakage, and an adjusting unit coupled electrically to said mixer for outputting a control signal thereto to control a current operating state of said mixer, said adjusting unit being further coupled electrically to said detecting unit, and determining whether there is a reduction in the extent of local oscillation leakage based on the detection signal from said detecting unit. In operation, the adjusting unit maintains an adjusting direction for the control signal upon determining that the extent of local oscillation leakage is reduced, reverses the adjusting direction upon determining that the extent of local oscillation leakage is not reduced, and adjusts the control signal according to the adjusting direction.

Abstract: The device may include a contactless element and a set of least two auxiliary elements. Each auxiliary element may include a slave SWP interface connected to a same master SWP interface of the contactless element through a SWP link, and a management module configured for activating at once only one slave SWP interface on the SWP link.

Abstract: A down-converter for receiving a multiband radio frequency signal (RF) and a local oscillator signal comprises a frequency divider and a heterodyne receive chain. The frequency divider is configured to divide the local oscillator signal and provide different divided local oscillator signals. The heterodyne receive chain comprises a first stage mixer and second stage mixers. The first stage mixer is configured to mix the multiband radio frequency signal and either the local oscillator signal or a divided local oscillator signal to generate a first intermediate frequency signal. Each second stage mixer is configured to mix the first intermediate signal and a divided local oscillator signal to generate second intermediate frequency signals that each represent a band from the multiband radio frequency signal. The frequency divider is configured to provide a different divided local oscillator signal to each of the second stage mixers.

Abstract: A method and apparatus for providing an oscillating signal within a transmitter/receiver circuit is described. The transmitter/receiver circuit may include an oscillator that generates an oscillating signal that may be provided to a low power, low gain mixer of the transmitter/receiver circuit along a shorter circuit path that includes low power circuitry, such as low power buffers and low power frequency dividers. The oscillating signal may also be provided to a high power, high gain mixer along a longer circuit path that includes high power circuitry, such as high power buffers and high power frequency dividers. Specifically, the low power circuitry is adapted to consume less power in an ON state than the high power circuitry in an ON state, and the shorter circuit path has a shorter electrical path length than the longer circuit path.

Abstract: A node comprising a receiver for i) receiving at least two signals streams comprising bit sequences and ii) evaluating which bit sequence that is most likely to have been received for a certain sent symbol for each signal stream. The receiver for calculating metrics indicative of which bit sequence that initially is most likely to correspond to a certain sent symbol, the metrics being used a soft value calculation where the receiver is arranged for addition of metric data for a certain signal stream corresponding to an added bit sequence for each case where the available metrics are incomplete for performing the estimation. The missing bit is inserted in the added bit sequence and chosen such that it corresponds to a symbol with the shortest Euclidian distance to the symbol with the said corresponding bit sequence initially being indicated as most likely to correspond to a certain sent symbol.

Abstract: A wireless communications device may include a portable housing and a temperature-compensated clock circuit carried by the portable housing. The device may further include a wireless receiver carried by the portable housing for receiving timing signals, when available, from a wireless network, and a satellite positioning clock circuit carried by the portable housing. A clock correction circuit may be carried by the portable housing for correcting the temperature-compensated clock circuit based upon timing signals from the wireless network when available, and storing historical correction values for corresponding temperatures. The clock correction circuit may also correct the temperature-compensated clock circuit based upon the stored historical correction values when timing signals are unavailable from the wireless network, and correct the satellite positioning clock based upon the temperature-compensated clock circuit.

Abstract: In accordance with an embodiment, a method includes determining an amplitude of an input signal provided by a capacitive signal source, compressing the input signal in an analog domain to form a compressed analog signal based on the determined amplitude, converting the compressed analog signal to a compressed digital signal, and decompressing the digital signal in a digital domain to form a decompressed digital signal. In an embodiment, compressing the analog signal includes adjusting a first gain of an amplifier coupled to the capacitive signal source, and decompressing the digital signal comprises adjusting a second gain of a digital processing block.

Abstract: A wireless communication unit has two or more communication modes including one or more mobile phone mode, in which mobile phone mode the wireless communication unit is able to transmit or receive wireless signals via an antenna from and/or to a mobile phone network in accordance with a communication protocol. The unit includes a baseband module and a radiofrequency module. A radiofrequency interface of the baseband module is connected to the radiofrequency module, for receiving and/or transmitting baseband signals from and/or to the radiofrequency module. The radiofrequency module includes a baseband interface, for receiving and/or transmitting the baseband signals to the baseband module and an antenna interface (AI) connectable to an antenna for receiving and/or transmitting radiofrequency signals from and/or to the antenna. A clock system is connected to the radiofrequency interface and the baseband interface.

Abstract: A channel information feedback method adapted in a receiving end of a multiuser multiple input multiple output (MU MIMO) system has following steps. A subspace matrix and a magnitude matrix related to a transmitting end of the MU MIMO system are obtained according to a channel matrix corresponding to the receiving end. A first quantization is performed on the subspace matrix to generate a quantized subspace matrix. A second quantization is performed on an auxiliary information matrix to generate a quantized auxiliary information matrix, where the auxiliary information matrix is corresponding to the magnitude matrix and a residual subspace matrix, and the residual subspace matrix includes residual subspace information after the first quantization is performed on the subspace matrix. The quantized subspace matrix and the quantized auxiliary information matrix are fed back to the transmitting end through an uplink channel.

Abstract: A radio-frequency (RF) apparatus, which may reside in a receiver or transceiver, includes receive-path circuitry. The receive-path circuitry includes a poly-phase filter and a harmonic filter. The poly-phase filter accepts an input signal and generates two output signals. One output signal of the poly-phase filter constitutes an in-phase (I) signal. The other output signal of the poly-phase filter constitutes a quadrature (Q) signal. The a harmonic filter couples to the poly-phase filter. The harmonic filter accepts as input signals the in-phase and quadrature output signals of the poly-phase filter.

Abstract: A method and device for managing a reference oscillator within a wireless device is presented. The method includes selecting reference oscillator parameters associated with the lowest reference oscillator error, where the selection is based upon reference oscillator parameters derived using different technologies within a wireless device, acquiring a satellite based upon the selected reference parameters, determining the quality of the satellite-based position fix, and updating the reference oscillator parameters based upon the quality of the satellite-based position fix.

Abstract: The invention discloses a dual frequency multiplexer by which a first and second coaxial harmonic oscillator type band pass filters are disposed in a box. The box includes a base body, a cover plate and a cover body. The two coaxial harmonic oscillator type hand pass filters are located on the base body and spaced each other by a metal plate; the multiplexer port, first and second ports are positioned on lateral side of the base body. The blocking capacitors are contained in the coaxial chamber of the two coaxial harmonic oscillator type band pass filters. The cover plate is secured on the base body; the first and second direct current circuits are placed on the cover plate; the low pass filters of the first and second direct current circuits are fixed on an edge of a top surface of the coaxial chamber by means of a support member; the cover body and the base body are fastened with each other. The blocking capacitors each are of distributed parameter capacitor.

Abstract: A communication system comprising one or more transceiver units of a first type and one or more transceiver units of a second type capable of communicating with the transceiver units of the first type; each transceiver unit of the first type comprising: a frequency comparison unit for comparing the frequency of a signal received from a transceiver unit of the second type with a reference frequency; a feedback signal generator for generating a feedback signal dependent on the result of that comparison; and a transmitter for transmitting that signal to the transceiver unit of the second type; and each transceiver unit of the second type comprising: a local frequency reference unit on which the frequency of signals transmitted by it are dependent; and a frequency adjustment unit for receiving the feedback signal and adjusting the local frequency reference unit in dependence on the feedback signal.

Abstract: A method of transmitting data using a generalized phase shift based precoding or an extended phase shift precoding scheme in a multiple-antenna system using a plurality of subcarrier and a transceiver for supporting the same are disclosed. A phase shift based precoding matrix may be generalized and determined by a product of a diagonal matrix for phase shift and a unitary matrix for maintaining orthogonality in spatial domain. The diagonal matrix may be extended by a product of a precoding matrix for increasing channel power and the diagonal matrix for phase shift. The design of the transceiver can be simplified or communication efficiency can be improved by generalizing and extending the phase shift based precoding.

Abstract: The present invention provides a method of processing signal data comprising generating a first clock signal and a second clock signal and processing the signal data using the first clock signal and the second clock signal. While processing the signal data, the phase difference between the first clock signal and the second clock signal is measured and corrected for so that a target phase difference between the first clock signal and the second clock signal is maintained.

Abstract: A radio apparatus includes a first receiver that is a processing unit for amplifying and frequency converting a radio signal received via an antenna, thereby outputting an IF signal; a detector unit for detecting a preamble signal from the IF signal; a second receiver for amplifying and quadrature demodulating the radio signal, thereby generating an I-signal and a Q-signal; a demodulator unit for demodulating the I-signal and Q-signal to generate a data signal; and a control unit for halting the operation of the first receiver and further activating the second receiver when the detector unit detects the preamble signal and for activating the first receiver and halting the operation of the second receiver when the demodulator unit completes the demodulation of the I-signal and Q-signal.

Abstract: Circuits, systems, and methods are disclosed for controlling multiple antenna receive paths in a wireless communication device. In some embodiments, the circuit may include a pair of receiving antennas, a first receive path including a VCO coupled to receive a PLL signal and a first mixer coupled to receive a first signal from the VCO and a signal from one of the antennas, and a second receive path integrated separately from the first receive path including a second mixer coupled to receive a second signal from the VCO and a signal from the other antenna. By utilizing the output of the VCO to tune the first and second mixers in the first and second receive paths to the same phase and frequency, control of the multiple antenna receive paths may be optimized.

Abstract: A wireless communications device may include a portable housing and a temperature-compensated clock circuit carried by the portable housing. The device may further include a wireless receiver carried by the portable housing for receiving timing signals, when available, from a wireless network, and a satellite positioning clock circuit carried by the portable housing. A clock correction circuit may be carried by the portable housing for correcting the temperature-compensated clock circuit based upon timing signals from the wireless network when available, and storing historical correction values for corresponding temperatures. The clock correction circuit may also correct the temperature-compensated clock circuit based upon the stored historical correction values when timing signals are unavailable from the wireless network, and correct the satellite positioning clock based upon the temperature-compensated clock circuit.

Abstract: A receiving apparatus and method of a Multiple Input Multiple Output (MIMO) system are provided. The receiving apparatus includes a clock generation/delay compensation unit for generating a clock, an antenna switching unit for temporally dividing signals received through multiple antennas by performing switching according to the clock, a radio frequency (RF) chain to be shared for converting the temporally divided signals into baseband signals, and an analog to digital converter (ADC) to be shared for converting the converted signals into digital signals and for outputting the converted signals according to the clock. Accordingly, the number of RF chains used to implement a MIMO RFIC is reduced.

Abstract: A technique to share a local oscillator signal between two radio frequency integrated circuits (RFICs). The local oscillator signal generated internally by one RFIC is ported to the other RFIC for use in transmit or receive operation. The local oscillator signal that is ported may be an RF local oscillator signal. Each RFIC may include a bi-directional port circuit that can be operated to make the RFIC a master, slave or may be totally disabled to disable the porting feature. This is particularly useful in RFICs that are used to communicate using MIMO radio algorithms which rely for optimum performance on phase and frequency coherency among a plurality of transmitters and a plurality of receivers.

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.

Abstract: A communications transceiver incorporating diversity architecture for utilization with a wireless communications network and having improved receiver sensitivity is disclosed. In a first embodiment of the invention, the communications transceiver comprises a pair of antennas connected to a pair of amplifiers and a selector connected between the amplifiers and the intermediate frequency stage of the transceiver for providing selective operation of the communications transceiver with either antenna of the pair of antennas. In a second embodiment of the invention, the communications transceiver comprises a pair of antennas, a pair of amplifiers and a selector disposed between the first amplifier and the intermediate frequency stage of the transceiver and between the second antenna and the second amplifier for providing selective operation of the communications transceiver with either of the antennas.

Abstract: A digital relay and concomitant method comprising employing an analog-to-digital converter, and via control logic providing oversampled output of the converter to determine likely digital values corresponding to the output, and wherein the control logic substantially eliminates aliasing resulting from waveform transients in input to the converter, and wherein no anti-aliasing filter is employed providing the input. Also, a digital relay and concomitant method comprising employing an analog-to-digital converter, and via control logic providing oversampled output of the converter to determine via Fourier transform likely digital values corresponding to the output, and wherein the control logic substantially eliminates aliasing resulting from waveform transients in input to the converter.

Abstract: A wireless communications device (100) includes a primary radio frequency branch (134) and a diversity branch (136), which is enabled and disabled to balance performance and power consumption. Diversity mode operation of the device is controlled, for example, based on one or more of an estimated channel quality indicator, data reception, data rate, state or mode of the station, estimated signal to noise ratio of a pilot signal, battery power level, distance from a serving cell, among other factors.

Abstract: A dual band WLAN (Wireless Local Area Network) communications technique is provided where a frequency synthesizer unit generates an LO (Local Oscillator) signal at a frequency between both frequency bands and two downconversion units and/or two upconversion units are provided. One of the units performs conversion between the LO signal and an IF (Intermediate Frequency) signal while the other conversion takes place between the IF signal and a zero-IF or low-IF signal. Signal processing is performed on the zero-IF or low-IF signal.

Abstract: A low-noise amplifier in a receiver has a differential mode of operation and at least one single-ended mode of operation. A control signal is used to select between or among the modes and the switching between differential and single-ended operations may be performed on the fly.

Abstract: Aspects of a method and system for enabling simultaneous FM transmitter and FM receiver functions using an integrated Bluetooth Local Oscillator Generator (LOGEN). A Bluetooth® LOGEN may be utilized to generate Bluetooth® signal that comprise (I) and (Q) components for use in Bluetooth® communication. The Bluetooth® LOGEN may then be utilized by a DDFS to generate FM radio (I) and (Q) signals for FM radio reception. The Bluetooth® LOGEN may also be utilized by a second DDFS to generate FM radio (I) and (Q) signals for FM radio reception. The Bluetooth® signals may be kept at the same frequency, or reduced in frequency, for use in clocking the DDFS. A frequency word may also be utilized to clock the two DDFS. The outputs of each DDFS may be a constant frequency while the inputs to each DDFS may vary in frequency.

Abstract: A technique to share a local oscillator signal between two radio frequency integrated circuits (RFICs). The local oscillator signal generated internally by one RFIC is ported to the other RFIC for use in transmit or receive operation. The local oscillator signal that is ported may be an RF local oscillator signal. Each RFIC may include a bi-directional port circuit that can be operated to make the RFIC a master, slave or may be totally disabled to disable the porting feature. This is particularly useful in RFICs that are used to communicate using MIMO radio algorithms which rely for optimum performance on phase and frequency coherency among a plurality of transmitters and a plurality of receivers.

Abstract: A local oscillator (LO) buffer circuit comprises first and second LO buffers arranged in a cross coupled configuration. The first LO buffer generates in-phase output signals in response to in-phase input signals, and quadrature output signals from the second LO buffer. The second LO buffer generates the quadrature output signals in response to quadrature input signals and the in-phase output signals. The LO buffers may include inductive loads. The LO buffers may include MOS transistors or bipolar junction transistors.

Abstract: Variable phase ring oscillators are described that provide a linear phase progression between adjacent elements in an antenna array by providing a symmetric ring configuration of tuned amplifiers and a single phase shifter. The ring topology is coupled to a single PLL that allows for direct modulation and demodulation of arbitrary waveforms without using RF up/down converting mixers. The PLL distributes the transmit waveforms to all antenna elements in the transmit mode and combines the received waveforms in the receive mode without any complicated power distribution network. Ultra-wideband architectures and methods are described that utilize a first reference signal source, a VPRO, and a second reference signal source. Related methods are controlling an array and beam steering are also described.

Abstract: Embodiments of the present disclosure allow for a linear phase progression between adjacent elements in array by providing a symmetric ring configuration of tuned amplifiers and a single phase shifter. This ring topology is coupled to a single phase locked loop (“PLL”) that allows for direct modulation and demodulation of arbitrary waveforms without using RF up/down converting mixers. In addition, the PLL distributes the transmit waveforms to all antenna elements in the transmit mode and combines the received waveforms in the receive mode without any complicated power distribution network.

Abstract: A direct conversion satellite tuner is fully integrated on a common substrate. The integrated tuner receives an RF signal having a plurality of channels and down-converts a selected channel directly to baseband for further processing. The integrated tuner includes on-chip local oscillator generation, tunable baseband filters, and DC Offset cancellation. The integrated tuner can be implemented in a completely differential I/Q configuration for improved electrical performance. The entire direct conversion satellite tuner can be fabricated on a single semiconductor substrate using standard CMOS processing, with minimal off-chip components. The tuner configuration described herein is not limited to processing TV signals, and can be utilized to down-convert other RF signals to an IF frequency or baseband.

Abstract: A technique includes generating an analog voltage to control a frequency for an oscillator. The analog signal is converted into a digital signal, and the frequency is controlled in response to the digital signal.

Abstract: An integrated multi-core RF device includes a common amplifier which outputs an amplified RF signal. A common transmission line is configured to supply the amplified RF signal to a plurality of common transmission line distribution connections. Each receiver core of a plurality of receiver cores has a receiver core RF input coupled to one of the plurality of common transmission line distribution connections. Each core is configured to be tunable to a channel and to output at least one baseband output per channel. The integrated multi-core RF device is configured to concurrently down convert a plurality of channels to corresponding down converted baseband signals. The integrated multi-core RF device is configured to allow dynamic selection of the one or more of the plurality of channels over time. A method to recover a DSCC receiver IC is also described.

Abstract: A mobile communication device (202) and peer mobile communication devices (204, 206) are capable of direct voice and data communication. The mobile communication device has a reference oscillator (104) which is used for generating operating frequencies, and is subject to frequency errors resulting from manufacturing tolerances, heat, and other error sources. The mobile communication device receives a frequency correction message (506) from a peer mobile communication device that has calibrated its reference oscillator. The frequency correction message contain offset information which is used by the mobile communication device to determine its offset (316) from a nominal frequency (302).

Abstract: A radio receiver for diversity has a first receiving unit and a second receiving unit for diversity-receiving a signal of a radio frequency. The first receiving unit has a first mixer for converting the received signal of the radio frequency into an IF signal of a first intermediate frequency by an upper local method, and a first filter coupled to the output side of the first mixer. The second receiving unit has a second mixer for converting the received signal of the radio frequency into an IF signal of a second intermediate frequency by a lower local method, and a second filter coupled to the output side of the second mixer. The radio receiver can improve receiving sensitivity.

Abstract: A method for reducing adjacent channel interference begins by determining a desired channel of a radio frequency (RF) signal. The method continues by determining a plurality of potential local oscillations for the desired channel. The method continues by determining a proximal power level of an image frequency of each of the plurality of potential local oscillations to produce a plurality of proximal power levels. The method continues by selecting one of the plurality of potential local oscillations for down converting the desired channel based on the plurality of proximal power levels.

Abstract: In a wireless transmitting device which performs transmission by an OFDM using a plurality of subcarriers orthogonal to each other, a plurality of preambles to which a plurality of different subcarrier groups selected from a plurality of subcarriers within an OFDM signal band are allocated are transmitted by using a plurality of transmit antennas, and data is transmitted by using the antennas after the preambles are transmitted.

Abstract: A technique to share a local oscillator signal between two radio frequency integrated circuits (RFICs). The local oscillator signal generated internally by one RFIC is ported to the other RFIC for use in transmit and/or receive operation. The local oscillator signal that is ported may be an RF local oscillator signal. Each RFIC may include a bi-directional port circuit that can be operated to make the RFIC a master, slave or may be totally disabled to disable the porting feature. This is particularly useful in RFICs that are used to communicate using MIMO radio algorithms which rely for optimum performance on phase and frequency coherency among a plurality of transmitters and a plurality of receivers.

Abstract: Disclosed herein is a demodulating device including, first high-frequency receiving means and second high-frequency receiving means for receiving a high-frequency signal of one of a first frequency and a second frequency, first signal strength detecting means and second signal strength detecting means for detecting strengths of signals received by the first high-frequency receiving means and the second high-frequency receiving means, respectively, and strength determining means for performing control so as to make the second high-frequency receiving means receive a high-frequency signal of the first frequency when the first high-frequency receiving means is made to receive the high-frequency signal of the first frequency and the second high-frequency receiving means is made to receive a high-frequency signal of the second frequency and when the second signal strength detecting means does not detect a predetermined signal strength within a predetermined time after the first signal strength detecting means dete