Abstract: A method and system of optimizing transmit beam forming in a multiple radio wireless system is provided. A stimulus signal can be provided to an analog receive input of a device under test (DUT), wherein the DUT includes multiple radios. A receive phase and amplitude can be measured at baseband using the stimulus signal for each radio. At this point, a receive weight and its conjugate can be determined using the receive phases and amplitudes. A calibration vector and its conjugate can also be determined, wherein a product of the receive weight conjugate and the calibration vector conjugate generate a transmit weight. This transmit weight can be applied to transmit signals during the transmit beam forming using the multiple radios.

Abstract: An antenna receives an RF signal and an RF signal at different frequency bands. An oscillator outputs a local oscillator signal at a frequency f1. An oscillator outputs a local oscillator signal at a frequency f2. A modulator modulates the frequency based on the local oscillator signal at the frequency f1 and the local oscillator signal at the frequency f2, and generates a plurality of local oscillator signals at different frequencies. A frequency converter mixes the plurality of local oscillator signals, at different frequencies, generated by the modulator, with the RF signal and the RF signal, and generates baseband signals of the RF signal and the RF signal. A signal processor performs a predetermined process for the baseband signals generated by the frequency converter.

Abstract: A television broadcast receiving apparatus can change an oscillation frequency of a local oscillation signal or a tuning frequency of an intermediate frequency signal in a reception channel, and changes the reception characteristic to an optimum reception characteristic. In this way, the television broadcast receiving apparatus effectively reduces SN ratio deterioration due to interference of the outside of a reception band such as adjacent channel interference.

Abstract: A system includes a weighting module, a mixer module, and a frequency selective impedance (FSI). The weighting module is configured to receive an input signal having an amplitude and to generate weighted outputs. Amplitudes of the weighted outputs have ratios relative to the amplitude of the input signal. The mixer module has switches configured to receive the weighted outputs and to generate a staircase waveform when the switches are clocked by clock signals. Amplitudes of steps of the staircase waveform are based on the ratios. The FSI is configured to communicate with the switches. The switches are configured to translate an impedance of the FSI centered on a first frequency to a second frequency determined by a frequency of the clock signals.

Abstract: Radio frequency (RF) architectures for spectrum access networks are provided. Embodiments of the invention generally provide a radio frequency (RF) architecture for customer premise equipment (CPE) for use in, for example, IEEE 802.22 wireless regional area networks (WRANs). In some embodiments, the CPE RF architecture includes two receive chains with a directional antenna and an omni-directional antenna, respectively. The CPE RF architecture facilitates opportunistic out-of-band spectrum sensing and WRAN signal receiving that are performed in parallel with data transmission.

Abstract: Disclosed are a wireless communication system, method, and site controller for mitigating at least one of a transmission timing synchronization loss and a receiving timing synchronization loss at a base station. The method includes determining, at a first base station, a loss of a timing reference the timing reference is used by the first base station for timing synchronization of at least one of a transmission and reception of wireless data. The timing synchronization is predefined and common between at least the first base station and a second base station. The method further includes adjusting, in response to the determining, at least one of a transmit guard time and a receive guard time by at least one symbol time.

Abstract: Methods may be provided to simultaneously receive first and second RF (radio frequency) carriers over respective first and second RF carrier frequencies. More particularly, the first and second RF carriers may be provided at an RF mixer stage. During a first time period, the first and second RF carriers may be down converted through the RF mixer stage using a first RF mixer frequency to generate first downconverted signals, and the first downconverted signals may be processed to provide first and second DC carriers corresponding to the first and second RF earners. During a second time period, the first and second RF carriers may be downconverted through the RF mixer stage using a second RF mixer frequency to generate second downconverted signals with the first and second RF mixer frequencies being different, and the second downconverted signals may be processed to provide the first and second DC carriers corresponding to the first and second RF carriers. Related devices are also discussed.

Abstract: Disclosed herein is a phase-locked circuit including: a phase-locked section including a voltage controlled oscillator having a capacitance bank and changing oscillation frequency according to voltage information, the phase-locked section phase-locking an oscillating signal of the voltage controlled oscillator to a reference signal; and a calibration section having a voltage correcting function for supplying an appropriate calibration voltage to the voltage controlled oscillator in performing frequency calibration for the voltage controlled oscillator; the calibration section including a counter circuit, a first storage circuit and a second storage circuit, a comparator circuit, a control circuit, a voltage generating circuit, and a processing circuit.

Abstract: A signal processing apparatus includes: a digital processing unit to which a digital input signal is supplied, which performs a digital process on the digital input signal to produce a digital signal, and which produces a control signal designating a specific time period when an amplitude of an analog output signal is to be lowered; a DA-conversion unit which converts the digital signal to produce an analog signal; and a variable gain unit which adjusts an amplitude of the analog signal to produce the analog output signal, and which lowers the amplitude of the analog output signal during the specific time period designated by the control signal.

Abstract: The present invention relates to a method, apparatus, and computer program product, wherein a level of a first signal received via first channel is determined. Additionally, a moving average of a plurality of determined levels of the first signal is obtained, and the moving average is subtracted from the determined level. The subtraction result is then used for estimating a noise variance of a second signal received via a second channel.

Abstract: A double frequency-conversion receiving circuit used for a radio-frequency SIM card, including a low-noise amplifier (01), a high-medium-frequency mixer (02), a low-medium-frequency mixer (03), a local oscillator (04), a quadrature I/Q circuit (05), and a low-medium-frequency processing circuit (07), characterized in that it also includes a frequency divider (06) that performs N frequency dividing to a high-local-oscillation signal generated by the local oscillator (04), wherein the divided low-local-oscillation signal is inputted into the quadrature I/Q circuit (05), the outputted I/Q local-oscillation signal is inputted into the low-medium-frequency mixer (03) to obtain, after mixing, a low-medium-frequency signal, and the low-medium-frequency signal is further processed by the low-medium-frequency processing circuit (07) to output the signal needed, which has gone through the double frequency-conversion.

Abstract: A method and system for managing Digital to Time Conversion (DTC) is provided. The method comprises receiving a first Radio Frequency (RF) signal and a second RF signal. The second RF signal is a phase-shifted first RF signal. The method further comprises converting the first RF signal to a first Intermediate Frequency (IF) signal and the second RF signal to a second IF signal. Further, a time delay between the first IF signal and the second IF signal is estimated based on a time difference measurement technique. The second RF signal is processed based on the estimated time delay to compensate for a delay error associated with the second RF signal.

Abstract: 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.

Abstract: An apparatus and method for receiving and processing multiple independent, uncorrelated RF signals is presented. The apparatus includes a Hybrid-Direct Conversion Receiver incorporating front end branches, protocol-specific digital processing branches, an interference detector, a correlator, and an offset control for controlling oscillator sources. The front end branches each contain a preselector that filters received signals and a mixer that down converts the received signal to an IF offset from a reference frequency by a unique offset. The bandwidth of an IF processor is partitioned into sub-channels corresponding to the different offsets and is wider than the combination of the sub-channels. The interference detector and correlator determine whether a particular desired signal is degraded by interference signals and select a new sub-channel. This information is provided to the offset control, which adjusts a LO source coupled to the corresponding down mixer accordingly.

Abstract: A signal receiving device is provided which can prevent the imbalance occurring between in-phase and quadrature signals. A polarity of a local oscillator output signal to be outputted from a local oscillator 13 is switched by a polarity switching unit 14 in a time division way. Each of signals outputted from the polarity switching unit 14 is frequency divided by a frequency divider 16. The frequency-divided local oscillation signal is supplied to a mixer 34. Frequency conversion of a receiving signal is performed by the mixer 34 which receives the signal and local oscillation signal to demodulate received data.

Abstract: In an electronic control apparatus for vehicles, there is provided a main microcomputer activated when a given activation condition is met and a sub-microcomputer to which a power control signal controlling power supply to the sub-microcomputer is supplied. A first power supply unit supplies, via a first supply line, power supply voltage to the main microcomputer for activation, and a second power supply unit supplies, via a second supply line different from the first supply line, power supply voltage to the sub-microcomputer for activation when the sub-microcomputer receives the power control signal. The main microcomputer determines whether or not the sub-microcomputer should be made to operate and performs a switchover between output and non-output of the power control signal to the second power supply unit based on the determined results, whereby the power supply to the sub-microcomputer is controlled.

Abstract: The present invention relates to a mixer circuit and method of frequency transformation, wherein an input signal is switched in accordance with a first local oscillator signal and in accordance with at least one second local oscillator signal having a smaller duty cycle than said first local oscillator signal, or having a respective predetermined phase shift with respect to said first local oscillator signal. Output signals obtained by the switching in accordance with the first and at least one second local oscillator signals are summed and the polarity of one of said first local oscillator signal and said at least one second local oscillator signal is switched in response to a control input, to thereby switch between a harmonic-rejection mode and a sub-harmonic mixing mode.

Abstract: 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 multi-band SAW-less RF receiver front-end and techniques to share components of FTNFs included within the multi-band SAW-less RF receiver front-end are presented.

Abstract: According to an aspect of the invention, an oscillating circuit includes: a first MOS transistor having a first drain terminal and a first source terminal; a load element connected to the first drain terminal; and an oscillator connected to the first source terminal and outputs a fundamental signal and a harmonic signal, wherein the harmonic signal is amplified so that the amplified harmonic signal is output from the first drain terminal.

Abstract: A radio-frequency receiver. The radio-frequency receiver includes a first and second low noise amplifier (LNA), a local oscillating module, and a first, second, and third mixer. The first LNA amplifies a first RF signal. The local oscillating module generates a first, second and third local oscillating signals. The first local oscillating signal is generated according to the second local oscillating signal. The first mixer mixes the first RF signal with the first local oscillating signal to generate an intermediate frequency signal. The second LNA amplifies a second RF signal. The second and third mixers can be operated in two modes. The second and third mixers mix the intermediate frequency signal to generate a first and second baseband signal respectively in the first mode, and the second and third mixers mix the second RF signal with the second and third oscillating frequency respectively in a second mode.

Abstract: A modulation circuit for use in a radiofrequency transmitter includes a local oscillator circuit configured to generate one or more local oscillator signals at a desired frequency and with a duty cycle at or about twenty-five percent, and a modulator configured to generate one or more modulated signals responsive to the one or more local oscillator signals and one or more baseband information signals. In at least one embodiment, the modulation circuit includes a modulator comprising a combined mixing and transconductance circuit that includes a transistor circuit for each baseband information signal serving as a modulation input to the modulator. Each transistor circuit comprises a first transistor driven by the baseband information signal and coupling a modulator output node to a corresponding transconductance element, and a second transistor driven by one of the one or more local oscillator signals and coupling the corresponding transconductance element to a signal ground node.

Abstract: Methods and systems are provided for filtering packets in a wireless communication system in the to-mobile subscriber direction. This filtering is at least in part based on RF circuit state information. For example, a packet filter is used that either permits or denies packets from reaching a mobile subscriber based on whether there is already an established RF circuit to provide packets to the mobile subscriber. Alternatively, or in addition, the packet filter may consider the history of circuit state transitions associated with a particular mobile subscriber, the percentage (or aggregate number) of available airlink resources that are currently in use, and/or the length of time associated with the dormancy of a mobile subscriber's RF connection. In various embodiments, the packet filter may cause one or more packets to be sent to a mobile subscriber using a special data channel that does not require the establishment of an RF circuit.

Abstract: A receiving apparatus comprising: a first mixing unit to output first and second mixed signals each having a first frequency that is a frequency difference between a received signal and a first local oscillator signal, the first and second mixed signals having phases substantially orthogonal to each other; a phase control unit to output second and third local oscillator signals each having a second frequency, the second and third local oscillator signals having a phase difference from each other corresponding to a phase difference between the first and second mixed signals; and a second mixing unit to add a signal obtained by mixing the first mixed signal and the second local oscillator signal, and a signal obtained by mixing the second mixed signal and the third local oscillator signal, to output an intermediate frequency signal having an intermediate frequency that is a difference between the first and second frequencies.

Abstract: A system includes at least a first array connected to a second array. The first array includes an odd number, greater than one, of unidirectionally-coupled non-linear first array elements. The second array includes an odd number, greater than one, of unidirectionally-coupled non-linear second array elements. The second array elements are unidirectionally-coupled in a direction opposite the coupling direction of the second array elements. The first array is configured to receive an input signal and down-convert the input signal. The second array is configured to receive the down-converted input signal, further down-convert the down-converted input signal, and output a down-converted output signal. The down-converted output signal is down-converted to a multiple of the frequency of the input signal proportional to the number of arrays of the system. The system may operate at frequencies greater than 1 GHz and may be contained in a microchip or on a printed circuit board.

Abstract: A radio frequency transceiver (102), including a transmitter (104), a duplexer (108) and a direct-conversion receiver (106) including a mixer (140 and 141). An IIP2 calibration system (170), coupled to the transceiver, includes an IIP2 coefficient estimator (172) for calculating an estimate of second-order distortion intermodulation distortion, and an IIP2 controller (174) for adjusting an IIP2 tuning port of the mixer in the receiver to minimize second-order distortion intermodulation distortion in the receiver that may be caused by the receiver receiving a transmit RF signal leaking through the duplexer.

Abstract: A method for managing a plurality of call origination requests is provided. The method includes receiving (204) the plurality of call origination requests from a plurality of communication devices. Further, the method includes queuing (206) the plurality of call origination requests, based on a predefined policy, when a base station is operating in a congestion mode. Furthermore, the method includes processing (208) each call origination request of the plurality of call origination requests, based on the queued plurality of call origination requests.

Abstract: 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.

Abstract: A system and technique for providing to flexible, programmable frequency estimators and spectrum analyzers that can operate over extremely large bandwidths and yet provide high spectral resolution are described. The acquisition time and hardware complexity of one technique scale as O(N), where N denotes the number of frequency bins acquired. Embodiments are disclosed in which architectures are implemented using exponentially-tapered transmission lines and filter cascades.

Abstract: A method and system for calibrating a plurality of modules in a communication system is provided. The method may include selecting a plurality of modules with at least one output signal and calibrating an amplitude of each selected module to be within a specified range if the amplitude is out of the specified range via a gain control processing circuit of the selected module, wherein the plurality of modules may be calibrated in an order starting with a first module located at an input of a signal path and ending with a module located at an output of the signal path. The DC component and amplitude of the envelope of the output signal may be detected by circuitry within the selected module. Muxes may be utilized to route the DC component and amplitude of the envelope to a feedback control processing circuit.

Abstract: A radio frequency transceiver (102), including a transmitter (104), a duplexer (108) and a direct-conversion receiver (106) including a mixer (140 and 141). An IIP2 calibration system (170), coupled to the transceiver, includes an IIP2 coefficient estimator (172) for calculating an estimate of second-order distortion intermodulation distortion, and an IIP2 controller (174) for adjusting an IIP2 tuning port of the mixer in the receiver to minimize second-order distortion intermodulation distortion in the receiver that may be caused by the receiver receiving a transmit RF signal leaking through the duplexer.

Abstract: According to one embodiment, a radio frequency receiver includes a quadrature mixer for converting radio frequency signals to baseband signals or intermediate frequency signals. The quadrature mixer includes an in-phase passive mixer and a quadrature-phase passive mixer. Each passive mixer includes a mixer core having a plurality of mixer input switch transistors and a plurality of output switch transistors connected to the mixer input switch transistors. Clock circuitry generates a first set of clock signals and a second set of clock signals. The first set of clock signals has a frequency twice that of the second set of clock signals. The first set of clock signals is arranged to drive the mixer input switch transistors and the second set of clock signals is arranged to drive the output switch transistors.

Abstract: An arctangent detector according to the present invention generates a demodulated signal based on the result of arctangent calculation of the ratio between an in-phase component and a quadrature component obtained from a frequency modulation (FM) received signal that are perpendicular to each other. A median filter substitutes the median value of the sample values obtained by sampling the demodulated signal generated by the arctangent detector as many times as the point number for the current value of the demodulated signal and outputs a resultant signal. The point number altering unit alters the point number in the median filter based on the signal intensity of the FM received signal.

Abstract: A downconversion mixer with IM2 cancellation includes a mixer, an IM2 generator, and a scaling unit. The mixer frequency downconverts an input RF signal with an LO signal and generates an output baseband signal. The IM2 generator includes first and second field effect transistors (FETs) that receive the input RF signal and generate an intermediate signal having IM2 distortion. The scaling unit scales the intermediate signal to generate a scaled signal and further combines the scaled signal with the output baseband signal to cancel IM2 distortion in the output baseband signal. The IM2 generator may further include first and second amplifiers coupled between the source and gate of the first and second FETs, respectively. Different amounts of IM2 distortion and different temperature variation patterns may be generated in the intermediate signal by using different gains for the amplifiers.

Abstract: Digital mixers which permit mixing of asynchronous signals may be constructed of Rapid Single Flux Quantum (RSFQ) logic elements. The logic elements may include an RSFQ non-destructive readout cell (NDRO), an RSFQ D flip-flop, an RSFQ XOR circuit, and an RSFQ T flip-flop. A binary tree arrangement of T flip-flops can be used to provide in-phase and quadrature phase-divided replicas of a reference signal. The mixing elements can be either an XOR circuit, a dual port NDRO circuit functioning as a multiplexer or an RS type NDRO functioning as an AND gate. The RSFQ logic elements utilize Josephson junctions which operate in superconducting temperature domains.

Abstract: A dual-LO mixer is disclosed. The dual-LO mixer receives an input signal, a first reference signal of a first reference frequency, and a second reference signal of a second reference frequency, and performs a frequency translation to convert the input signal into an output signal, wherein the frequency difference between the input signal and the output signal is a sum or a difference of the first reference frequency and the second reference frequency.

Abstract: There is provided a wide-band direct conversion transmitting apparatus including: a local oscillation unit generating first, second, and third oscillation signal pairs each including a pair of signals having a phase difference of 90°; an image rejection mixer unit mixing baseband transmission signals including an I signal and a Q signal having a phase difference of 90° with the first oscillation signal pair; a harmonic rejection mixer unit mixing each of the first, second, and third oscillation signal pairs with the baseband transmission signals; and an output signal selecting unit selecting output signals from the image rejection mixer unit or from the harmonic rejection mixer unit.

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: There is provided a dual band receiver receiving frequency signals in different bands, the receiver including: a first down converter converting a first band signal into a first intermediate frequency signal; a second down converter converting a second band signal into a second intermediate frequency signal; a first voltage control oscillator supplying a first oscillation frequency to the first down converter; a second voltage control oscillator supplying a second oscillation frequency to the second down converter; a first filter passing the first intermediate frequency signal within a desired bandwidth; a second filter passing the second intermediate frequency signal within a desired bandwidth; and a clock generator converting the first oscillation frequency of the first voltage control oscillator into sampling frequencies corresponding to integer multiples of first and second oscillation frequencies and supplying the sampling frequencies to first and second AD converters, respectively.

Abstract: 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.

Abstract: To detect phase mismatches between in-phase and quadrature signals of a quadrature demodulator. The phase mismatches can be detected using the signals obtained by removing high frequency components of output of a multiplier by a low pass filter, the output being the product of the in-phase signals of which low frequency components are removed by a first high pass filter by the quadrature signals of which low frequency components are removed by a second high pass filter.

Abstract: A modulation circuit for use in a radiofrequency transmitter includes a local oscillator circuit configured to generate one or more local oscillator signals at a desired frequency and with a duty cycle at or about twenty-five percent, and a modulator configured to generate one or more modulated signals responsive to the one or more local oscillator signals and one or more baseband information signals. In at least one embodiment, the modulation circuit includes a modulator comprising a combined mixing and transconductance circuit that includes a transistor circuit for each baseband information signal serving as a modulation input to the modulator. Each transistor circuit comprises a first transistor driven by the baseband information signal and coupling a modulator output node to a corresponding transconductance element, and a second transistor driven by one of the one or more local oscillator signals and coupling the corresponding transconductance element to a signal ground node.

Abstract: A communication system with variable filter bandwidth includes a first mixer circuit configured to receive a communication signal and shift the frequency range of the communication signal to a first frequency range. A second mixer circuit is configured to receive the same communication signal and shift the frequency range of the communication signal to a second frequency range. An activation circuit is coupled to the first and second mixer circuits so as to provide an activation signal that activates at least one of the mixer circuits. A plurality of filter circuits are provided such that each filter circuit is configured to receive a signal from a corresponding mixer circuit, when the corresponding mixer circuit is activated.

Abstract: A two stage mixer is configured to reduce the power levels of out of band spurious output signals or spurs, such as the leakage from the second stage mixer by way of phase modulation power spreading. The local oscillator signal applied to first mixer stage is phase modulated while the local oscillator signal applied to the second mixer stage is inverse modulated. As such, a problematic spur, such as leakage from the local oscillator applied to the second mixer stage is spread so that the power levels of the spur are distributed a wider bandwidth instead of concentrating the power levels at single frequencies, thus reducing the power level at any single frequency. By utilizing phase modulation, the need for relatively complex and expensive filters is eliminated.

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.

Abstract: 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.

Abstract: A method of generating an output signal comprises receiving an input signal, mixing the input signal with a reference signal having a reference frequency to obtain an intermediate frequency signal having an intermediate frequency, filtering the intermediate frequency signal using a filter having a filter characteristic that is configured according to the intermediate frequency and performing frequency translation on the filtered intermediate frequency signal to obtain the output signal.

Abstract: 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.

Abstract: A radio signal receiver includes an input for receiving an input signal having an input carrier frequency modulated by a payload signal to be detected. A frequency converter changes the carrier frequency of the input signal and produces an intermediate signal that is an image of the input signal, and has a carrier frequency equal to an intermediate frequency. A filter circuit filters the intermediate signal. A demodulator eliminates a component, with a frequency equal to the intermediate frequency, from the filtered intermediate frequency, and produces the payload signal. The receiver also includes a detection circuit to produce a level signal representative of a level of the payload signal. A control circuit applies a control signal representative of the level signal to a control input of the frequency converter, the filter circuit and the demodulator.

Abstract: A method is for reducing a DC component of an input signal transposed into baseband and being generated by a first frequency transposition stage starting from an initial signal and from a transposition signal. The method includes amplifying the transposed input signal in a first amplifier. The first amplifier receives at a DC offset compensation input, a compensation signal extracted from an output signal of a second amplifier subjected to a compensation of a offset DC voltage of the second amplifier. The method also included alternating between receiving at an input of the second amplifier, a first auxiliary signal from an auto-transposition of a transposition signal in a second frequency transposition stage and a second auxiliary signal from a transposition of the initial signal in the second frequency transposition stage with the transposition signal.

Abstract: A transceiver configuration has an integrated circuit (IC) with an A/D and/or D/A converter, a VCO with a reference oscillator, which provides a sampling clock for the A/D and/or D/A converter, and a digital data processing circuit. The IC is connected to a radio-frequency section, the frequency converter stage of which is operated with a beat frequency derived from the controllable oscillator frequency foz. A capacitive resonant element of the reference oscillator is disposed outside of the IC.