Abstract: A communication device supporting multiple wireless protocols may share a common gain element in a coordinated manner. A first wireless protocol circuitry of the communication device may enter an active state, and in response to entering the active state, may determine whether a second wireless protocol circuitry of the communication device is active and whether the common gain element is currently shared. The gain element may be adjustable to amplify signals by an adjustable amount. The first wireless protocol circuitry may take control of the gain element from the second wireless protocol circuitry in response to determining that the second wireless protocol circuitry is active and the gain element is currently shared.

Abstract: Certain embodiments of the present disclosure provide a method for frequency-domain gain control in system utilizing orthogonal frequency division multiplexing (OFDM) multiple input multiple output (MIMO). The proposed method reduces the complexity of the system while maximizing the internal accuracy of the OFDM MIMO decoder and preserving the performance of the system.

Abstract: Various techniques for dynamically reducing power usage in a wireless receiver are disclosed. A receiver unit receives a wireless signal over a channel and processes the wireless signal, including dynamically changing one or more of the settings of the receiver unit to control its power usage. These setting are changed in response to one or more power setting values that are generated based on a first set of information that includes state information for the channel. The receiver unit may dynamically change a first setting that causes the bias current applied to an analog-to-digital converter to be changed. The channel state information may include information indicative of a received signal strength indication (RSSI), information indicative of a packet error rate (PER) for packets encoded on the wireless signal, and header error check (HEC) and/or cyclical redundancy check (CRC) errors for data packets encoded on the wireless signal.

Abstract: A fixed point finite impulse response (FIR) filter comprising: 1) an input stage for receiving an input signal as a sequence of input samples comprising: i) delay elements connected in series for receiving and shifting N sequential input samples; ii) multipliers, each multiplier receiving a selected one of the N sequential input samples from the delay elements and multiplying the selected input sample by a corresponding coefficient to produce an intermediate product; and iii) a summer for receiving and adding N intermediate products from the multipliers to produce an output sum signal comprising a sequence of output sum samples; and 2) an output stage for truncating k least significant bits (LSBs) from each of the output sum samples, wherein k is a variable number.

Abstract: A fixed point finite impulse response (FIR) filter comprising: 1) an input stage for receiving an input signal as a sequence of input samples comprising: i) delay elements connected in series for receiving and shifting N sequential input samples; ii) multipliers, each multiplier receiving a selected one of the N sequential input samples from the delay elements and multiplying the selected input sample by a corresponding coefficient to produce an intermediate product; and iii) a summer for receiving and adding N intermediate products from the multipliers to produce an output sum signal comprising a sequence of output sum samples; and 2) an output stage for truncating k least significant bits (LSBs) from each of the output sum samples, wherein k is a variable number.

Abstract: Techniques for optimizing the power consumption of existing low cost multi-gain state power amplifiers (PA) to increase the talk time of wireless communication devices are described. In an exemplary embodiment a device, such as a baseband processor, operates to set a multistage PA having at least two gain states for amplifying a transmit signal to a lowest power consuming gain state. The device calculates a transition power level as a function of an identified maximum power reduction (MPR) value and switches the PA to a higher gain state from a lower gain state when a transmission power level is higher than the calculated transition power level.

Abstract: A fixed point finite impulse response (FIR) filter comprising: 1) an input stage for receiving an input signal as a sequence of input samples comprising: i) delay elements connected in series for receiving and shifting N sequential input samples; ii) multipliers, each multiplier receiving a selected one of the N sequential input samples from the delay elements and multiplying the selected input sample by a corresponding coefficient to produce an intermediate product; and iii) a summer for receiving and adding N intermediate products from the multipliers to produce an output sum signal comprising a sequence of output sum samples; and 2) an output stage for truncating k least significant bits (LSBs) from each of the output sum samples, wherein k is a variable number.

Abstract: An apparatus comprising a plurality of switchable full step mixer unit cells, wherein each switchable full step unit cell is configured to, when the full step transceiver mixer unit cell is turned on, increase the gain experienced by an electronic signal by a full step increment, and wherein the step increment is substantially constant regardless of temperature; and at least one switchable partial step mixer unit cell configured to, when the partial step transceiver mixer unit is turned on, increase the gain experienced by the electronic signal by a predetermined step increment less than that of a full step, and wherein the partial step increment is substantially constant regardless of temperature.

Abstract: An adaptive current control circuit for reduced power consumption and minimized gain shift in a variable gain amplifier. An automatic gain control circuit provides gain control voltages in response to a gain control signal. The gain control voltages are used by the variable gain amplifier to set the gain of the output signal for wireless transmit operations. The adaptive current control circuit receives the same gain control voltages for reducing current to the variable gain amplifier during low gain operation, while providing higher currents during high gain operation. The current that is provided is a hybrid mix of proportional to absolute temperature (PTAT) current and complementary to absolute temperature (CTAT) current for minimizing temperature effects on the gain. The ratio of PTAT current and CTAT current is adjustable for specific temperature ranges to further minimize temperature effects on the gain.

Abstract: An incoming RF signal can be amplified in a RF front end of a RF receiver by conveying the signal through one of a multiple amplification paths. On each path, the gain can be controlled by RF automatic gain control (AGC) circuits. Each amplification path can be designed to handle incoming signals in a designated power range and to optimize receiver performance characteristics such as the noise figure (NF) and odd harmonic linearity in that power range. Signal power can be measured at different locations of the receiver and bypass switches can be used to convey the RF signals down one of the multiple paths based on the power measurements, according to executable logical code. An incoming signal power hysteresis can be applied to stabilize the system. Further, signal power averaging and switch delaying mechanisms can be employed to stabilize the system for rapidly fluctuating signals.

Abstract: A system and method are provided for reducing dynamic EVM of an integrated circuit power amplifier (PA) used for RF communication. In a multistage PA, the largest amplification stage is biased with a high amplitude current pulse upon receipt of a Tx enable, before receipt of the RF signal data burst. The high amplitude current pulse causes a large portion of the total ICQ budget of the multistage PA to pass through the largest amplification stage causing the entire integrated circuit to rapidly approach steady-state operating conditions. A smoothing bias current is applied to the largest amplification stage after the pulse decays to compensate for transient bias current levels while standard bias circuitry is still approaching steady-state temperature.

Abstract: A power amplifier controller circuit controls a power amplifier based upon an amplitude correction signal indicating the amplitude difference between the amplitude of the input signal and an attenuated amplitude of the output signal. The power amplifier controller circuit comprises an amplitude control loop and a phase control loop. The amplitude control loop adjusts the supply voltage to the power amplifier based upon the amplitude correction signal. The amplitude correction signal may also be split into two or more signals with different frequency ranges and provided respectively to different types of power supplies with different efficiencies to generate the adjusted supply voltage to the power amplifier. The phase control loop adjusts the phase of the input signal based upon a phase error signal indicating a phase difference between phases of the input signal and the output signal to reduce phase distortion generated by the power amplifier.

Abstract: Disclosed herein are systems and methods for recovering a sub-carrier signal from a multiplexed signal having an embedded pilot tone signal. The recovery system includes circuitry for recovering a pilot signal from the received multiplexed signal, for generating a frequency-doubled signal from the recovered pilot signal, and for phase-shifting the frequency-doubled signal by a pre-determined phase difference from the embedded pilot tone signal. Another recovery system includes circuitry for recovering a pilot signal from the received multiplexed signal, for phase-shifting the pilot signal by a pre-determined phase difference from the embedded pilot tone signal, and for generating a frequency-doubled signal from the phase-shifted signal.

Abstract: Provided are apparatus and method for receiving signals in a wireless communication system.

Abstract: A method and system for controlling a gain of a low noise amplifier to be applied to i) a first signal from a first communication device, and ii) a second signal from a second communication device, in which i) the first signal conforms to a first communication protocol, and ii) the second signal conforms to a second communication protocol. The method includes determining a first signal strength indicator corresponding to a signal strength of the first signal; determining a second signal strength indicator corresponding to a signal strength of the second signal; and controlling the gain of the low noise amplifier based on at least i) the first signal strength indicator and ii) the second signal strength indicator.

Abstract: Embodiments of a system for calibrating the image rejection of a receiver include an image-rejection correction circuit that modifies the gain and phase of a first channel of a baseband image signal. The image-rejection correction circuit may include a summing circuit and first and second variable-gain elements. In one implementation, a filter receives a corrected first channel from the image-rejection correction circuit and an unmodified second channel of the image signal, while a controller analyzes power measured at the output of the filter, and adjusts the variable-gain elements to reduce the power of the image signal.

Abstract: A low-noise amplifier includes first and second transconductance paths and first and second variable capacitive dividers. The first transconductance path has a first terminal for receiving a first input signal, a control terminal, and a second terminal for providing a first output signal. The second transconductance path has a first terminal for receiving a second input signal, a control terminal, and a second terminal for providing a second output signal. The first variable capacitive divider has a first terminal for receiving the first input signal, a second terminal coupled to a reference voltage terminal, and an intermediate terminal coupled to the control terminal of the second transconductance path. The second variable capacitive divider has a first terminal for receiving the second input signal, a second terminal coupled to the reference voltage terminal, and an intermediate terminal coupled to the control terminal of the first transconductance path.

Abstract: Aspects of a system for improving efficiency over power control for linear and class AB power amplifiers may include a current source circuit that enables determination of a bias current level for a PA circuit within an IC die based on an amplitude of an input modulation signal. The PA circuit may enable generation of an output signal based on a differential input signal and the input modulation signal to the current source circuit. A generated bias voltage may be applied to a transformer external to the IC die, but internal to an IC package containing the IC die and/or a circuit board containing the IC package. One or more amplifier bias voltage levels may be applied to the PA circuit wherein the amplifier bias voltage levels may be derived from the generated bias voltage level and/or the determined bias current level.

Abstract: An apparatus such as a television signal receiver provides an AGC function which reduces cross-modulation distortion. According to an exemplary embodiment, the apparatus includes first and second amplifiers coupled in series and a gain control circuit. The gain control circuit controls the gains of the first and second amplifiers in response to the magnitude of the input signal. The gain of the first amplifier remains substantially unchaged at a first level while the magnitude of the input signal is within a first range. The gain of the second amplifier is gradually reduced in the first range. The gain of the first amplifier remains substantially unchaged at a second level, which is lower than the first level, while the magnitude of the input signal is within a second range. The gain of the second amplifier gradually reduced in the second range. The gain of first amplifier is gradually reduced at least in part of a third range while the magnitude of the input signal is within the third range.

Abstract: A switched current resistor (SCR) PGA for constant-bandwidth gain control includes an inverting amplifier, a feedback resistor forming a feedback loop between an output side and an input side of the inverting amplifier, and a switched current resistor (SCR) array connected in parallel to the feedback resistor, and configured to tune a gain range between a maximum and a minimum. The SCR array includes a plurality of switched resistors, each comprising a switch in series with a resistor. When the plurality of switched resistors are switched by a gain-control logic, a plurality of switched current sources and a plurality of grounded resistors are switched correspondingly to deliver a transient current, an equivalent of which flows through the plurality of grounded resistors out from the input side of the inverting amplifier, leading to a feedback factor of the PGA being constant.

Abstract: A wireless communication receiver includes a multitude of look-up tables each storing a multitude of DC offset values associated with the gains of an amplification stage disposed in the wireless communication receiver. The entries for each look-up table are estimated during a stage of the calibration phase. During such a calibration stage, for each selected gain of an amplification stage, a search logic estimates a current DC offset number and compares it to a previous DC offset estimate that is fed back to the search logic. If the difference between the current and previous estimates is less than a predefined threshold value, the current estimate is treated as being associated with the DC offset of the selected gain of the amplification stage and is stored in the look-up table. This process is repeated for each selected gain of each amplification stage of interest until the look-up tables are populated.

Abstract: Systems and devices for controlling frequency drift in satellite broadcast systems. A receiver antenna system for a direct broadcast satellite signal communications system in accordance with one or more embodiments of the present invention comprises an oscillator, a mixer, coupled to the oscillator, for converting satellite signals at a first frequency to signals at an intermediate frequency, an analog-to-digital (A/D) converter, coupled to the mixer, for receiving the signals at the intermediate frequency and for converting the signals at the intermediate frequency at near-real-time to a digital data stream, a Digital Signal Processor (DSP), coupled to the A/D converter, for processing the digital data stream, and a drift estimator, coupled to the DSP, the drift estimator determining a frequency drift of the oscillator, wherein the receiver antenna system corrects the frequency drift of the oscillator using the determined frequency drift.

Abstract: Volume control circuits for use in electronic devices are provided. Some embodiments of the present invention provide volume control circuits for use in electronic devices. The volume control circuits include a gain circuit, a limiter circuit, a power measurement circuit and a gain adjustment circuit. The gain circuit is configured to receive an input audio signal and amplify the input audio signal based on a gain. The limiter circuit is configured to limit the amplified input audio signal based on a peak safety limit and output an output audio signal having a peak value based on the peak safety limit. The power measurement circuit is configured to measure a power level of the output audio signal. The power level has an associated power safety limit. The gain adjustment circuit is configured to adjust the gain of the gain circuit responsive to the measured power. Related methods and electronic devices are also provided herein.

Abstract: In an exemplary embodiment, a phased array antenna comprises multiple subcircuits in communication with multiple radiating elements. The radio frequency signals are adjusted for both polarization control and beam steering. In a receive embodiment, multiple RF signals are received and combined into at least one receive beam output. In a transmit embodiment, at least one transmit beam input is divided and transmitted through multiple radiating elements. In an exemplary embodiment, the phased array antenna provides multi-beam formation over multiple operating frequency bands. The wideband nature of the active components allows for operation over multiple frequency bands simultaneously. Furthermore, the antenna polarization may be static or dynamically controlled at the subarray or radiating element level.

Abstract: Methods, systems, and machine-readable code for optimizing transmit power of a power amplifier using a Vbat monitor are disclosed and may comprise adjusting the gain of gain stages in a transmit path based on a control signal that is a function of a supply voltage signal, among other variables, derived from a supply voltage that may be used to power a transmit path. The supply voltage signal may be received from a power management unit or derived directly from a battery or other supply. The supply voltage signal may be compared to a reference signal, the result of which may be utilized to generate the control signal. The values for the control signals may be determined over a range of supply voltages and stored in a lookup table.

Abstract: A tuner for a wireless receiver is provided, which may include an input interface that is adapted to receive wireless signals, a mixer that is adapted to select a specific frequency from signals received at the input interface, and a controllable switch that is adapted to lead an output from the mixer towards a base-band unit of the receiver and to disconnect the output. The tuner may further include a controller which may be adapted to operate the controllable switch to disconnect the output of the mixer when the controller studies characteristics of the tuner and to reconnect the output of the mixer at other times. The studied characteristics may be associated with parasitic direct current voltages in the tuner, which may be associated with a low noise amplifier of the tuner, or programmable gain amplifier of the tuner or with both amplifiers.

Abstract: A radio receiver adapted to alternatively receive data over a communication channel in a first mode and a second mode. The second mode facilitates reception of data at higher data rates than the first mode. The radio receiver comprises a signal-processing unit and a control unit. The signal processing unit is adapted to determine a quality condition of the communication channel. The control unit is adapted to determine, based on the quality condition, whether the communication channel facilitates operation in the second mode and assess at least one configuration condition, one of the at least one configuration condition being that the communication channel is determined to facilitate operation in the second mode. The control unit is further adapted to configure the radio receiver to operate in the second mode when all of at least one configuration condition are fulfilled or to operate in the first mode otherwise. A method for controlling the radio receiver is also disclosed.

Abstract: The present invention provides a receiver with low power consumption. The receiver with low power consumption adjusts the gain of the programmable gain amplifier based on the automatic gain controller and further optimizes the gain bandwidth product by current-adjusting unit. The current-adjusting unit thus adjusts the current provided for the programmable gain amplifier, e.g. operational amplifier. Therefore, the gain bandwidth product of the programmable gain amplifier is optimized and the power consumption of the receiver is effectively decreased.

Abstract: Apparatus and methods are disclosed, such as those involving an RF receiver. One such apparatus includes a front end having an input and an output. The front end forms part of an RF signal receive path. The front end includes a front-end resistor configured to receive an input signal; and a passive mixer downstream of the front-end resistor on the receive path. The passive mixer mixes the input signal with a local oscillation signal. The front-end includes a transimpedance amplifier located downstream of the passive mixer on the receive path. The transimpedance amplifier includes an input and an output. The front end further includes a feedback resistor coupled between the input and output of the transimpedance amplifier. The gain of the front end is a ratio of the feedback resistance to the front-end resistance, and is temperature- and frequency-insensitive. The apparatus also provides relatively constant input impedance and high linearity.

Abstract: In one embodiment, a combined VGA-and-equalizer (VGA-EQ) circuit for a communication link includes a current-mode logic (“CML”) amplifier with an inductive load circuit. The CML amplifier has a gain control terminal and is operable to amplify, with an adjustable gain, a signal received at an input terminal and provide the amplified signal at an output terminal. The CML amplifier has a first gain at frequencies below a predetermined frequency value and a second gain at frequencies in a predetermined frequency range above the predetermined frequency value, wherein the second gain is higher than the first gain. The higher second gain of the VGA-EQ circuit causes a reduction in inter-symbol interference in a signal received by the receiver.

Abstract: This demodulation device receives and demodulates a digital broadcast wave. This demodulation device includes an RF search control unit (41) and a GI search control unit (42). The RF search control unit (41) determines whether or not there is a broadcast wave in a certain channel, in accordance with an intensity of a signal outputted from a tuner (12) for receiving a digital broadcast wave. The GI search control unit (42) determines whether or not the broadcast wave is digital, based on whether or not the signal outputted from the tuner (12) contains a guard interval. Thus, the demodulation device is capable of efficiently searching for a channel containing a digital broadcast wave.

Abstract: A method and apparatus are provided for calibrating an information-signal transmission line that includes elements for generating a control signal and transmitting information signals controlled by the control signals, and an amplifier of the information signals. The amplifier can be configured according to at least a first gain configuration associated with a first gain value, and a second gain configuration associated with a second gain value. The method includes obtaining, for each of the first and second gain configurations, first and second sets of initial values of the control signal, that correspond to first and second sets of measured power that overlap, and selecting, for each power-recovery setpoint value to which corresponds a first measured-power value of the first set and a second measured-power value of the second set, from the first and second calibrated values of the control signal, the calibrated value that meets a predetermined criterion.

Abstract: A digital amplifier amplifies an input signal from a tuner (107) which receives a broadcast wave of a set receiving frequency so as to suppress degradation of the high-band reproduction performance and lowering of the amplification efficiency.

Abstract: A communication apparatus includes a radio frequency (RF) apparatus. The RF apparatus includes an amplifier, and a signal detection circuit. The amplifier receives RF signals and amplifies those signals. The amplifier has an adjustable gain value. The signal detection circuit detects whether a received signal is an out-of-band radar signal depending on the gain value of the amplifier and a characteristic of the received signal.

Abstract: A wireless receiver is provided that includes a multi-step gain-control low-noise amplifier (LNA) stage and a mixer stage. The LNA stage is operable to amplify at least one input signal to generate at least one LNA output. The mixer stage is directly coupled to the LNA stage (without an intervening external bandpass filter) and is operable to down-convert the LNA output to generate a mixer output.

Abstract: A method and apparatus for controlling transmissions of data via an enhanced dedicated channel (E-DCH) are disclosed. A list of available transport format combinations (TFCs) is generated based on a plurality of dedicated channel medium access control (MAC-d) flows. An enhanced uplink medium access control (MAC-e) protocol data unit (PDU) is generated using a TFC which is selected from the list of available TFCs. The MAC-e PDU is forwarded to a hybrid-automatic repeat request (H-ARQ) process unit for transmission. The list of available TFCs is continuously updated by eliminating and recovering TFCs based on remaining E-DCH power, an E-DCH transport format combination set (TFCS), a power offset of a highest priority MAC-d flow that has E-DCH data to transmit, and a gain factor for each TFC.

Abstract: An apparatus including automatic gain control (AGC) includes at least one variable gain amplifier (VGA) operative to receive an input signal and to generate an amplified signal. A gain of the VGA is controlled as a function of at least a first control signal. The apparatus further includes an AGC circuit coupled to the VGA and being operative to generate the first control signal. The AGC circuit has a bandwidth that is controlled as a function of at least the amplified signal and a second control signal, the second control signal being indicative of a motion of the apparatus.

Abstract: A method and apparatus for optimization of RF receiver interference performance in a mobile phone operating in a TDMA communications system is disclosed. The battery supply voltage ripple of the battery of the mobile phone is measured and it is determining when the battery supply voltage ripple is greater than a predetermined level. The RF receiver is adjusted to improve the mode of operation of the RF receiver when the battery supply voltage ripple is greater than the predetermined level.

Abstract: Signals are received with a wider power range even through the use of existing AGCs than by conventional mobile communication terminals. In an AGC on one antenna side, in order to enable reception of a signal at a higher level, a target TA of a dynamic range DA of this AGC is changed to a value 5 dB higher than a value defined as a standard TS. On the other hand, in an AGC on another antenna side, in order to enable reception of a signal at a lower level, a target TB of a dynamic range DB of this AGC is changed to a value 5 dB lower than the value defined as the standard TS.

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: A GPS baseband architecture provides flexibility and power consumption and chip area usage advantages. The GPS baseband architecture includes a first stage having a preamplifier coupled to a low noise amplifier, which is coupled to a mixer. A PLL provides the mixer with a frequency to convert a signal to a higher intermediate (IF) frequency. The output of the mixer is fed to a poly-phase filter. The output of the poly-phase filter is fed to a programmable gain amplifier (PGA), whose output is fed to an analog-to-digital converter (ADC) to produce an output GPS signal. A saturation bit of the ADC is used to control the PGA through a digital amplifier gain control (AGC) circuit.

Abstract: A wireless device that can process signals according to multiple wireless protocols simultaneously and without signal loss. The wireless device may comprise an antenna and first and second wireless protocol circuitry. The first wireless protocol circuitry comprises a shared gain element that amplifies signals that are processed by each of the first and second wireless protocol circuitry. Since the third signals are amplified by the shared gain element prior to being split out to the respective protocol circuitry, the first and second portions of the amplified third signals do not have significant signal loss relative to the third signals provided by the antenna. Thus the wireless device can receive and process wireless signals according to both the first and second protocols simultaneously without any significant signal losses due to splitting of the receive signal.

Abstract: A direct conversion receiver (200) includes a low noise amplifier (LNA) (213), at least one baseband amplifier (119, 123 and 127), register banks (250 and 251) for storing a plurality of offset data corresponding to at least two LNA gain settings and a plurality of baseband gain settings, a DC offset correction system (235) for providing a DC offset signal, a state machine (275) for sequencing through each of the plurality of baseband gain settings and through enable and disable states for the LNA, and a processor (290) programmed to activate the state machine and to run the DC offset correction system.

Abstract: An improved admission control procedure for an admission control entity (e.g., Radio Network Controller (RNC), Node B, etc.) in a network that admits a terminal (mobile station, user equipment, etc.) having a certain receiver performance. Without improperly assuming one receiver performance or referring to a reference minimum receiver performance to calculate the resources that will be used, more accurate radio resources that should be used by the terminal when admitted to the cell can be determined by using appropriate information about the receiver performance of the terminal to be admitted.

Abstract: An enhanced programmable automatic level control loop comprising an input for receiving an input RF signal; a level modulator, wherein the level modulator receives the input RF signal and a control signal and wherein the level modulator produces a first signal; a mixer that receives the first signal and mixes it with an LO signal to produce a second signal; a programmable attenuator that receives the second signal and produces an output signal; a level detector that monitors RF power of the output signal and produces a DC voltage proportional to the RF power; and wherein the DC voltage is received at a loop amplifier which produces the control signal.

Abstract: A receiver for a wireless communication device comprising a mechanism for performing spur mitigation. An AGC unit of the receiver is operable to determine when an amplitude of an ADC output signal associated with a received RF signal is outside a predetermined amplitude range. The AGC unit is operable to modify a gain associated with a VGA such that the ADC output signal has an amplitude within the predetermined amplitude rage. The first spur mitigation unit is operable to determine an estimate of a spur signal of the ADC output signal and remove the spur signal from the ADC output signal based on the estimate of the spur signal. The first spur mitigation unit comprises a moving average filter operable to generate the estimate of the spur signal. The AGC unit is further operable to reset the moving average filter of the first spur mitigation unit when the AGC unit modifies the gain associated with the VGA.

Abstract: In TDD mobile networks, an incoming signal is received during a time period where no uplink communication takes place. The incoming signal is measured and analyzed to determine a noise level. Based on the noise level and on an uplink signal level from expected in a future uplink time slot, a gain for the automatic gain controller is set for use in future uplink communications. The gain is set to optimize the operation of an analog-to-digital converter.

Abstract: A wireless communication circuit has a second control circuit which reduces the gain of the differential converter when the signal level of the RF signal is at least a specified level and the RF signal includes a disturbing wave of a predetermined level or higher.

Abstract: Transceivers with multiple gain stages that include open loop and closed loop amplifiers are subject to differential non-linearity (DNL) errors in their total gain versus gain index curve due to the gain step variability of the open loop amplifiers. The initial and time varying DNL can be reduced by a control loop that uses the relative gain step precision of the closed loop amplifiers and of passive attenuators to establish a control loop to reduce the DNL of the total gain.

Abstract: A vehicle antenna includes a first Automatic Gain Control (AGC) unit and a second AGC unit. The first AGC unit may attenuate an input signal based on the strength of the input signal, and then output the attenuated signal to a transistor. The second AGC unit may control a power to be supplied or not to the transistor using a switching function based on the strength of the input signal. With the antenna, the signals of a strong electric field as well as the signals of a weak electric field adjacent to the strong electric field can be effectively controlled.