Abstract: A wireless network device includes a signal receiving module that receives an RF signal, and a signal processing module that includes an automatic gain control (AGC) module and that generates control signals when a gain of the AGC module changes based on the RF signal. The network device includes a control module that selectively measures N time intervals between one of adjacent and non-adjacent control signals, wherein N is an integer greater than 1, and that selectively determines that the RF signal is a radar signal when the N time intervals are substantially equal.

Abstract: A method, algorithm, circuits, and/or systems for demodulation in an amplitude modulated (AM) radio receiver are disclosed. In one embodiment, a radio receiver can include an amplifier configured to receive a radio frequency (RF) input signal and a gain control signal, and provide an amplified signal, an automatic gain control (AGC) circuit configured to receive a high threshold comparator output and provide the gain control signal, a mixer configured to combine the amplified signal and a local oscillation signal and provide a mixed output, a high threshold comparator configured to compare the mixed output with a reference level and provide the high threshold comparator output, and a low threshold comparator configured to compare the mixed output with the reference level and provide an output of the radio receiver.

Abstract: An antenna device that is placed adjacent to an antenna 5 for receiving a high frequency signal and includes an impedance matching circuit 6 and an amplifying circuit 21 to which a DC control voltage is supplied from a demodulating device 3 through a feeder cable 4 for transmitting the high frequency signal to the demodulating device 3, wherein the DC control voltage is set to a value for adjusting a frequency characteristic of the impedance matching circuit 6 within an allowable range corresponding to a received frequency. A small and inexpensive antenna device having a simple circuit configuration and good reception sensitivity is implemented.

Abstract: Provided is automatic gain control (AGC) in which a feedback filter has a parameter that is changed based on information regarding data-packet boundaries. In one representative embodiment, the bandwidth of the filter temporarily is increased, or the time constant of the AGC filter temporarily is decreased, within a vicinity of each actual or potential packet boundary.

Abstract: An embodiment of the present invention provides a method of closed loop MIMO calibration in a wireless communication system, comprising detecting that station calibration is obsolete and requires calibration, determining a range of automatic gain control which the station wants to calibrate and determining a list of transmission power for an Access Point (AP) in communication with the station, initiating by the station the calibration by sending the power list and N channel sounding preambles, where N is the number of transmit antennas at the station; and sending back by the AP a channel matrix and L sets of channel sounding preambles with a different transmission power level for each set, where L is the number of entries in the power list.

Abstract: A method and arrangement for noise variance and SIR estimation in a UTRAN Node B or User Equipment estimates the SIR (SIR(l) . . . SIR(K)) at the output of a detector by using an estimate ({circumflex over (?)}2) of the detector input noise variance to provide an estimate ({circumflex over (?)}z2) of the detector output noise variance. The detector input noise variance is derived from a midamble portion in the received signal. By deriving the transfer function of the detector an estimate of the detector output noise variance is estimated. The estimated output noise variance then allows an improved estimate of the SIR (SIR(l) . . . SIR(K)) at the detected output.

Abstract: A received low-frequency standard radio wave, which is an amplitude modulation signal, is converted to an intermediate frequency signal Sa, and is output to a detection circuit and an AGC circuit. The detection circuit and AGC circuit generates an RF control signal Sf1 and IF control signal Sf2 from the input intermediate frequency signal Sa, and controls an RF control circuit and IF control circuit by outputting the generated RF control signal Sf1 and IF control signal Sf2 to the RF control circuit and IF control circuit. By this a radio wave reception device can speed up AGC operation.

Abstract: A wideband mixer includes a core mixer having input terminals and output terminals for, respectively, receiving differential input signals and providing amplified differential output signals. A steering module is coupled to the core mixer for receiving differential reference signals and providing bi-phase modulated amplified differential output signals. The core mixer is configured to provide a value of gain between the differential input signals and the differential output signals. A bandwidth peaking network is coupled to the core mixer and includes (a) a first coil and a first resistor connected in series and (b) a second coil and a second resistor connected in series. The first coil and resistor and the second coil and resistor, respectively, are coupled to the core mixer for receiving the amplified differential output signals. The bandwidth peaking network is configured to increase the frequency bandwidth of the core mixer.

Abstract: Disclosed is a system and method of adjusting an audio signal for a communication device. The method comprises: identifying a characteristic associated with the signal and identifying its quality threshold; identifying a first set of adjustment parameters for the signal when the threshold is exceeded; and identifying a second set of adjustment parameters when it is not exceeded. Also, the device: monitors for a current setting value for the characteristic; and detects whether the current setting value is above or below the quality threshold. If the value is above, then the device produces a first output signal value utilizing a DSP, a processing filter defined in the DSP, values of the first set of adjustment parameters and the signal value. If the value is below, the device produces a second output signal value utilizing the DSP, the filter, values of the second set of adjustment parameters and the signal value.

Abstract: In one aspect, the present invention includes an automatic volume control (AVC) circuit to receive a demodulated signal and provide an output signal at a substantially constant volume. The circuit may be implemented in hardware, software, and/or firmware to perform digital demodulation, programmable amplification, and high pass filtering to provide a substantially constant volume output.

Abstract: The invention relates to gain calibration in a transceiver unit (100) having a transmitter unit and a receiver unit and a feed back coupling (165) between these. A signal level measurement unit (163) measures signal levels of a feedback signal through either the receiver unit or through a signal level detector (167). A reference signal level of the feedback signal is set by adjusting the transmitter until the signal level measurement unit (163) measures a predefined value when connected through the signal level detector (167). An absolute value of the transmitter gain is then calibrated. The signal level measurement unit (163) is connected through the receiver unit and the absolute gain of the receiver is calibrated. A gain is changed either in the receiver or the transmitter unit. The relative signal level change of the feedback signal is measured and used to calibrate the gain step.

Abstract: A communication station needs to autonomously and synchronously operate by maintaining an equal frame interval. A clock error is measured from a received packet in a wireless communication system where a beacon is transmitted periodically. This clock error is used to synchronize a counter to count the beacon's transmission/reception time and adjust a clock cycle deviation for synchronization. The synchronization is possible even in the case of restoration from a sleep state when the reference clock accuracy is poor. A period to maintain the sleep state can be extended irrespectively of the clock accuracy. It is possible to prevent desynchronization due to incorrect synchronization with an abnormal value.

Abstract: An apparatus is provided for improved temperature compensation of received RF signals. An RF receiver includes receiver circuitry which receives an RF signal and demodulates it to generate an output signal. Temperature compensation circuitry is coupled to the receiver circuitry and includes a diode having diode temperature characteristics. The temperature compensation circuitry adjusts the output signal of the receiver circuitry in response to the diode temperature characteristics to provide a tighter minimum trigger level.

Abstract: In a clock noise canceling circuit, a coupler extracts a signal from a clock signal. A filter selects a harmonic component of a preset frequency in the extraction signal from the coupler. A phase shifter phase inverts the harmonic component of the preset frequency from the filter. An AGC amplifier amplifies the phase-inverted harmonic component from the phase shifter. Also, a combiner combines the amplified component from the phase shifter with the clock signal to eliminate the harmonic component of the preset frequency from the clock signal. A power detector detects a power level of the harmonic component of the preset frequency in an output signal of the combiner. Additionally, a controller controls gain of the automatic gain control amplifier based on the power level of the harmonic component detected by the power detector, thereby canceling noises.

Abstract: A received signal level is detected in each of a wide band, middle band, and narrow band and each detected signal is converted to a digital signal. A DSP 18 determines the enabled/disabled state of an LNA 3 and an attenuator 4 as well as a gain adjustment amount based on the signal level of each band. For example, the gain adjustment is not performed when the signal level of the narrow band including a desired frequency is not larger than a prescribed value even the signal level of the wide band or middle band is larger than a prescribed value. When the signal level of the narrow band is larger than the prescribed value exceeding a gain adjustable limit level in the attenuator 4, the gain of the LNA 3 is adjusted, while maintaining the gain adjustable amount in the attenuator 4 around the limit level, to reduce the gain as a whole.

Abstract: An architecture for a receiver component in a wireless communications system is disclosed—one that supports both zero intermediate frequency (ZIF) and near-zero intermediate frequency (NZIF) operation. The architecture provides a down-conversion segment, and a local oscillator segment operatively associated with the down-conversion segment. An analog-to-digital conversion (ADC) segment is adapted to receive signals from the down-conversion segment and introduce the signals into a digital intermediate frequency (DIF) construct. The DIF construct performs a DC offset compensation or DC residue filtering on NZIF-based signals, and droop or mismatch compensation. Image removal is performed on NZIF-based signals, and DC offset compensation is performed on ZIF-based signals. Compensated signals are amplified to some nominal or desired level, and interpolation filtering of the amplified signals is performed prior to transmission thereof.

Abstract: Systems and methods for advanced signaling between stages of transmitters and/or receivers in a digital communication system. One or more intermediate frequency signals and one or more control signals may share the same cable. Also, systems and methods are provided for calibrating head end receiver gain to improve subscriber unit power control loop performance.

Abstract: A method in which one of a high-side mix mode and a low-side mix mode is selected in response to an interference characteristic of a desired channel of a radio frequency (RF) input signal is disclosed. In the high-side mix mode, a direct digital frequency synthesizer (130) is initialized to output a digital local oscillator signal at a first frequency suitable for performing a high-side mix of the desired channel to an intermediate frequency (IF). In the low-side mix mode, the direct digital frequency synthesizer (130) is initialized to output the digital local oscillator signal at a second frequency suitable for performing a low-side mix of the desired channel to said IF. The RF input signal is mixed with the digital local oscillator signal to provide an IF output signal at the IF.

Abstract: A receiver includes a gain stage, a peak detector and a processor. The gain stage provides an output signal, and the peak detector provides a binary indication of whether the output signal has reached a predetermined threshold. The processor controls the gain stage in response to the binary indication.

Abstract: An apparatus and method for controlling a digital AGC in a communication system in which power changes significantly from frame to frame. In the digital AGC controlling apparatus, an SNR estimator estimates an uplink SNR of a next frame. A power measurer measures uplink received power of every frame. A gain calculator estimates uplink power of an nth frame using an SNR estimate of an (n?1)th frame received from the SNR estimator and a received power measurement of the (n?1)th frame received from the power measurer, and calculates a gain to be applied to the nth frame in the digital AGC using the uplink power estimate of the nth frame.

Abstract: An AGC processing portion receives a burst signal of each received frame, and measures its received power level to perform gain control of a variable gain amplifier. Unlike a conventional wireless receiving device, a digital signal from an A/D converter is directly supplied to the AGC processing portion, without passing through an FIR filter. Accordingly, the input timing for the AGC processing portion does not include a delay due to the FIR filter, and an amplitude value can be adjusted to be appropriate from the leading part of each frame, suppressing the occurrence of a reception error due to AGC processing.

Abstract: A receiver may receive and process broadcasting signals in digital and analog forms. The receiver may include an amplifying input stage, a digital signal processing stage and an analog signal processing stage. The input stage may receive a broadcast signal. The digital signal processing stage may process a received broadcast signal and output a first quality information signal. The analog signal processing stage may process a received analog broadcast signal and outputs a second quality information signal. An evaluation unit may evaluate at least one of the first and second quality information signals and output a control signal to the amplifying input stage.

Abstract: An RF receiver front end includes a variable gain low noise amplifier and/or a variable gain mixer to provide gain variability in the receiver. This gain variability may be used during, for example, automatic gain control operations. In at least one embodiment, the variable gain LNA is a broadband device that is capable of supporting multiple wireless standards.

Abstract: An interference signal code power (ISCP) measurement is estimated for a receiver. Signals transmitted in a particular time slot are received and a gain of the received signals is controlled using an automatic gain control (AGC) device. An ISCP value corresponding to the gain value from a table is determined.

Abstract: Selectable sizes for a local oscillator (LO) buffer and mixer are disclosed. In an embodiment, LO buffer and/or mixer size may be increased when a receiver operates in a high gain mode, while LO buffer and/or mixer size may be decreased when the receiver operates in a low gain mode. In an embodiment, LO buffer and mixer sizes are increased and decreased in lock step. Circuit topologies and control schemes for specific embodiments of LO buffers and mixers having adjustable size are disclosed.

Abstract: An arrangement for processing the antenna signal of a radio receiver and for leading it to low-noise amplifiers LNA of parallel amplifier branches. On the transmission path of the receiver from the antenna to the amplifiers LNA, functionally different elements are combined into physically united elements, such as the conductors (432, 433) of the low-passing part of the antenna filter and the division conductors of the Wilkinson divider (430), and the conductor (441) of the phase-shifter and the inductive part (L1) of the LNA matching circuit. Each physically united element is a conductor, which is insulated from the ground plane by air or a low-loss dielectric material. The arrangement reduces the number of lossy parts between the antenna and the amplifiers, and placing these parts on an ordinary circuit board is also avoided. For these reasons, inferior noise values compared to the prior art can be allowed for each LNA.

Abstract: A conventional method of controlling the passband of a filter involves an increase in cost for a chip due to a large area of a detection circuit for determining the level of an interference wave. The present invention utilizes a result obtained by detecting the amplitude level of a signal with an automatic gain control circuit to appropriately control the passband of a filter. The amplitude level of all the signals including a desired wave and an interference wave is detected by utilizing the automatic gain control circuit to thereby control the passband of a filter on the basis of the result.

Abstract: A method for continuously determining the required dynamic range for an analog-to-digital converter by determining the received signal strength and using this received signal strength value in combination with the overall dynamic range for the ADC and the target resolution of the ADC to decode a radio channel in the absence of interference, wherein the target resolution is also related to the type of decoding to be performed subsequent to analog-to-digital conversion. The method allows for a reduction in power consumption associated with the ADC, especially when the incoming signal is received with few interfering radio channels and with a relatively high signal strength. The present method can be combined with gain control and analog alert detection.

Abstract: In a digital broadcast receiving tuner, a down-converter unit converts a high-frequency signal into a baseband signal directly or by once converting it into an intermediate frequency signal. A gain adjuster unit properly adjusts the actual level of the high-frequency signal and/or the intermediate frequency signal in correspondence with an AGC (automatic gain control) controlling voltage supplied from an external source. An amplifier properly adjusts the actual level of the baseband signal. A controlling unit properly controls the actual gain of the amplifier in response to a specific signal independent of the AGC controlling voltage. This configuration makes it possible to constantly secure optimal performance characteristics in whatever condition the received signal may be.

Abstract: When a RF signal is output, noise is prevented from appearing in the RF signal without degrading convenience. The MPU 11 of the set top box has functionally the RF determination portion 118 which determines whether or not a RF signal is being output, the antenna setting portion 117 which if it is determined by the RF determination portion 118 that the output of a RF signal is started, sets a smart antenna to preset one direction of the first predetermined number of directions and to preset one gain of the second predetermined number of steps of gains, and the change prohibition portion 119 which prohibits the change of the direction and gain of a smart antenna if it is determined by the RF determination portion 118 that a RF signal is being output.

Abstract: Described herein are ultra wide-band distributed RF (UWB-DRF) front-end receivers comprising composite cells distributed along transmission lines, where each composite cell comprises a low-noise amplifier (LNA) merged with a mixer. By merging the LNA and the mixer in each composite cell, the power consumption and chip area of the RF front-end is reduced. Further, the distributed architecture of the RF front-end allows it to operate over a wide bandwidth by absorbing the parasitic capacitances of the composite cells into the transmission lines of the RF-front end. Embodiments of the RF front-end provide wideband flat gain, low noise figure (NF), wideband linearity, and wideband matching at the inputs of the RF front-end. In an embodiment, a programmable resistance at the termination of the RF transmission line allows the RF front-end to trade off a few decibels of mismatch at the RF input for higher gain and lower NF.

Abstract: A wireless distribution system includes a number of remote units distributed in a coverage area to receive wireless signals and to provide the signals through the distribution system to input ports of a node where the signals are combined, a number of input power monitors operatively connected to one or more of the input ports to determine power levels of signals received at the input ports, variable gain controllers to control signals received at some or all of the input ports, a node to combine a plurality of signals from the plurality of input ports, and a controller to provide control signals to control one or more of the variable gain controllers.

Abstract: The present invention provides a DC offset correction system for a wireless communication device that removes a DC offset from a baseband receive signal during “training time” when the baseband receive signal should ideally have no DC content. In general, the DC offset correction system includes multiple configurable feedback loops that operate to remove or cancel the DC offset from the baseband receive signal. One or more of the multiple configurable feedback loops is activated for a period of time during operation when it is known that the received signal should ideally contain no DC content. This training time varies depending on the particular communication standard being used by the wireless communication device. For example, the training time may be during reception of the preamble and header of an IEEE 802.11 packet.

Abstract: An automatic gain control technique is disclosed for adjusting the gain of an IF amplifier in a communication system, such as an OFDM or DMT communication system. The gain of an RF amplifier is controlled by a known RF automatic gain control circuit that generates an RF gain value. The disclosed IF automatic gain control (AGC) circuit controls the gain of an IF amplifier in the receiver. The disclosed IF AGC monitors the RF gain value, as well as pre-FFT and post-FFT signal energy measurements performed before and after a fast Fourier transform (FFT) stage, respectively, to maintain a desired set point. The IF AGC adjusts the previous IF gain value by an amount opposite to the adjusted RF gain value, if any. If there is no RF gain adjustment, then the IF AGC will adjust the IF gain based on thresholds established for the pre-FFT and post-FFT measurements. If the pre-FFT measurement is within a desired tolerance of the pre-FFT threshold, then the IF gain will be lowered in stepped increments.

Abstract: In a communication receiver having a variable gain amplifier and an automatic gain controller, the automatic gain controller is operable to measure values of a system performance parameter indicative of the performance of the communication system, determine a statistical value of the system performance parameter, and adjust the variable gain of the amplifier in response to the statistical value to maintain the statistical value in a control range.

Abstract: A power amplifier can amplify an input radio frequency signal to produce an output radio frequency signal in response to a bias control signal. A programmable digital control unit produces the bias control signal and to transmit the bias control signal to the power amplifier.

Abstract: A method for precise transmit power adjustment in a wide personal area network (WPAN) is provided that includes coarse adjusting a power level of the radio signal by adjusting a gain setting of an amplifier that is used to power the radio signal, and fine adjusting the power level of the radio signal by adjusting a voltage level of an information signal that is provided to the amplifier so that the power level of the radio signal approaches a maximum allowable power level.

Abstract: A signal receiver (300) has a tuner (301), which receives an RF_IN signal and outputs a desired IF_OUT intermediate frequency signal to a demodulator (311). The demodulator (311) controls the RF_AGC and IF_AGC tuner gains according to an AGC characteristic of the tuner, to provide a constant level of the IF_OUT signal. The demodulator (311) sends to the processor (321) a digital stream of a desired signal TS. The processor comprises an AGC characteristic controller (327) for calculating the AGC characteristic of the tuner on the basis of a level of the desired signal and a strongest level of close signals, which are detected within the passband of the input filter (101) of the tuner (301) for the desired signal.

Abstract: A signal receiver (300) has a tuner (301), which receives an RF_IN signal and outputs a desired IF_OUT intermediate frequency signal to a demodulator (311). The demodulator (311), on the basis of the signal level received from the tuner and the AGC characteristic set by a processor (321), controls the RF_AGC and IF_AGC tuner gains. The demodulator operation may also base on the signal level read from the IF_OUT output of the IF_Amp amplifier. The demodulator (311) sends to the processor (321) a digital stream of a desired signal TS. The processor comprises an AGC characteristic controller (327) for calculating the AGC characteristic of the tuner on the basis of a level of the desired signal and a strongest level of close signals, which are detected within the passband of the input filter (101) of the tuner (301) for the desired signal.

Abstract: A method and system is disclosed for perform receiver gain control. A pilot signal is transmitted prior to each transmit period to facilitate an initial gain setting for a corresponding receiver period. This pilot signal has known properties and requires a much smaller receiver dynamic range than the rest of the traffic. An initial gain setting is derived based on the pilot signal received at a beginning of a corresponding receive period. A gain setting for traffic signals is then generated following the pilot signal in the receive period based on the initial gain setting.

Abstract: A mixer includes a reference current source, a programmable gain RF transconductance section or an RF transconductance section, switching quad native transistors or switching quad transistors, and a folded-cascoded common mode output section or an output section. When the mixer included the programmable gain RF transconductance section, the gain of the mixer is adjustable. When the mixer includes the switching quad native transistors, flicker noise of the mixer is reduced. When the mixer includes the folded-cascoded common mode output section, the mixer operates reliably from low supply voltages.

Abstract: A reception apparatus capable of calibrating a DC offset voltage fast and with high accuracy even in an environment in which interferer exist without causing noise characteristic degradation. In this apparatus, a digital signal processing section (108) controls the gain of a received signal at such a gain that predetermined reception quality is obtained. A time constant control circuit (110) controls the time constant and makes the amount of attenuation of the received signal of a low pass filter (106a) more moderate compared to the case where a DC offset voltage is not calibrated during DC offset voltage calibration. A voltage calibration circuit (111) calibrates the DC offset voltage generated in the received signal when controlling the gain.

Abstract: Implementations related to systems and devices that make use of a power detector multiplexer are presented herein.

Abstract: Systems and techniques are disclosed relating to communications. The systems and techniques involve supporting communications between a base station and a plurality of users by establishing an overhead channel between one of the users and the base station, and transmitting data from said one of the users to the base station on the overhead channel in response to a message having a threshold value related to a loading on the base station by the users. 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 power clipping circuit and method of the clipping circuit is provided. A power clipping circuit comprises, a selector which receives a baseband signal, and selects one of the baseband signal or a feed back signal, and outputs a selected signal, and a square clipping circuit which receives the selected signal, and limits an amplitude of the selected signal, and outputs a clipped signal, and a phase rotation circuit which receives the clipped signal, and rotates a phase of the clipped signal, and outputs a phase rotated signal to the selector as the feed back signal, and an amplitude scaling circuit which receives the phase rotated signal, and adjust the phase rotated signal to compensate an amplitude difference between the phase rotated signal and the clipped signal, and sends amplitude scaled signal, and a controlling circuit which controls the selector, the square clipping circuit, the phase rotation circuit and the amplitude scaling circuit.

Abstract: A receiver system design and architecture that implements a 3-step gain LNA and an analog VGA for a WCDMA handsets and local area base stations, providing a wireless device eliminating the use of external bandpass filter between low-noise amplifier and first mixer.

Abstract: An integrated circuit (IC) includes at least one baseband section, at least one radio frequency (RF) section, and an interface module. The interface module is operable to couple the at least one baseband section to the at least one RF section, wherein the interface module includes an analog interface module and a digital interface module.

Abstract: An attenuator system for adjusting the output of an HF signal source is described in which, between the signal source and an output, an electronic attenuator is disposed via mechanical switches on the input and output side. The mechanical switches can be switched in such a manner that, in one switch position, the electronic attenuator is inserted between the signal source and the output, and in the other switch position, a direct bypass is inserted between the signal source and the output.

Abstract: A system adjusts a receiving device in response to sensing symbols. An automatic gain control is adjusted in response to receiving a first symbol of a data unit from a first antenna. After adjusting the automatic gain control at least a second and a third symbol of the data unit are received. The automatic gain control in response to receiving a fourth symbol of the data unit from a second antenna is received. After adjusting the automatic gain control at least a fifth and a sixth symbol of the data unit is received. At least one of the first and second antenna is selected based upon a function of a first and second energy, calculated using the second and third symbol, and the fifth and sixth symbol, respectively.

Abstract: An apparatus for controlling a gain of a transceiving device in a terminal for a communication system is disclosed. A memory stores predetermined thresholds for level-by-level gain controlling. A signal intensity detector detects an intensity value of a received signal. Comparators compare the received signal intensity value with thresholds predetermined according to the current state. A state detector detects a gain level for the current state according to the comparison results provided from the comparators. A controller updates the current state according to the detected gain level, controls a gain of the transceiving device according to the updated current state, and sets thresholds corresponding to the updated current state in the comparators.