10 results about "Automatic gain controller" patented technology

A Radio Frequency (RF) communications device includes a pair of antenna terminals, which are connectable to an antenna. The device also includes an automatic gain controller, which is coupled to the antenna terminals for receiving an output current of the antenna. The automatic gain controller is operable to convert the output current of the antenna into a modulated current. The device further includes a rectifier, which is coupled to the automatic gain controller to receive the modulated current. The rectifier is operable to convert the modulated current into a rectified current. The device also includes a voltage limiter, which is coupled to the rectifier for receiving the rectified current. The voltage limiter is operable to convert the rectified current into a limited rectified voltage for supplying power to the RF communications device. An RF identification (RFID) tag comprising the RF communications device is also disclosed.

The invention relates to the technical field of optical communication, in particular to an optical receiving unit which is used for reducing DCD in an optical signal path of the optical receiving unit and can guarantee the receiving performance of the optical receiving unit. The optical receiver unit comprises a comparator and a controlled variable current source. Wherein the comparator is used for receiving a second voltage signal output by the automatic gain controller and receiving a reference voltage signal determined according to a target voltage signal output by the transimpedance amplification unit; and outputting a first control signal according to the second voltage signal and the reference voltage signal. The controlled variable current source is used for receiving the first control signal; and reducing a differential voltage signal output by a differential amplification unit according to the first control signal.

The application relates to a D-class audio power amplifier capable of self-adapting to improve light-load efficiency and reduce static current, which comprises an audio input module, an operational amplifier unit, a pulse width modulator and a power control module connected in sequence, wherein the operational amplifier unit and the power control module are connected with an automatic gain controller, and the pulse width modulator is connected with an oscillator; the power control module comprises a driving circuit, an adaptive power supply connected with the driving circuit and a full-bridge power tube; the driving circuit is connected with the pulse width modulator, and the full-bridge power tube is connected with the automatic gain controller. The adaptive power supply adjusts the power supply voltage of the driving circuit and the full-bridge power tube according to the size requirement of the audio output power, adaptively changes the gate voltage size of the full-bridge power tube, and reduces the power consumption of the circuit in the light load. The driving circuit adaptively adjusts the parallel number of the full-bridge power tube by detecting the size of the input voltage and the load power, reduces the static current, and improves the light-load efficiency.

The application discloses a kind of gain calculator and automatic gain control system.The gain calculator includes: gain calculation unit, for generating initial gain coefficient according to the gain signal corresponding to the output signal of variable gain amplifier;Polarity judging unit, for generating polarity signal according to the feedback signal of digital automatic gain controller;Hysteresis control unit, for generating gain coefficient adjustment value according to polarity signal;Gain adjustment unit, for generating gain coefficient according to initial gain coefficient and gain coefficient adjustment value.The technical scheme of the embodiment, by adding polarity judging unit, hysteresis control unit and gain adjustment unit, to generate corresponding gain coefficient adjustment value to correct gain coefficient when detecting that the signal strength of gain signal is abnormal, so as to adjust the signal strength of gain signal, which can realize effective correction of gain coefficient, and can ensure that the signal strength of gain signal is located in the working interval supported by digital automatic gain controller.

The invention relates to an antenna system of a vehicle for receiving broadcast signals and a method of operating the same. An antenna system of a vehicle includes: a first low noise amplifier (LNA) for adjusting a strength of a radio frequency (RF) signal received by an antenna element; a mixer for converting the adjusted RF signal received through the connection cable into an intermediate frequency (IF) signal; the second low noise amplifier is used for adjusting the intensity of the IF signal; a noise level detector for measuring a level of noise introduced into the connection cable; and a second automatic gain controller (AGC) for controlling the gain of the second LNA based on the intensity of the IF signal and the noise level.

An automatic gain controller includes multiple resistors, multiple switches, a buffer, a charge pump circuit and a voltage level shifter. The resistors are connected in series between an input terminal for receiving an input signal and an inverting input terminal of an operational amplifier. Each of the switches has a first terminal coupled to a corresponding one of the resistors, and a second terminal coupled to the inverting input terminal. The switches are respectively controlled by multiple switching signals so as to be turned on or turned off. The buffer generates a buffer signal according to the voltage at the inverting input terminal. The charge pump circuit generates a boost voltage according to the buffer signal and a clock signal. The voltage level shifter converts voltage levels of multiple control signals according to the buffer signal and the boost voltage to generate and respectively output the switching signals to the switches.

The invention discloses a digital automatic gain controller and an OOK receiver, and relates to the technical field of gain controllers, and the method comprises an input module, a frequency control module and a frequency adjustment module which are adaptively connected; the input module is used for receiving an input signal AGCIN and generating a counting control signal COUNT according to the input signal AGCIN, and based on the working state of the digital automatic gain controller, the frequency control module controls the sampling frequency fs when the frequency regulation module samples the counting control signal COUNT; the working states of the digital automatic gain controller comprise a starting working state and a normal working state which are carried out in sequence, and the sampling frequency fs of the frequency regulation module for sampling the counting control signal COUNT in the starting working state is greater than the sampling frequency fs of the frequency regulation module for sampling the counting control signal COUNT in the normal working state. The digital automatic gain controller has high working efficiency and high gain adjustment precision.

The invention relates to automatic gain control in a wireless local area network receiver. An example receiver includes a first power estimator operable to receive an in-phase signal; a second power estimator operable to receive a quadrature signal; a combiner coupled to outputs of the first power estimator and the second power estimator, the combiner having an output to supply estimated signal power; and an automatic gain controller coupled to the output of the combiner, the automatic gain controller operable to turn off one of the first power estimator or the second power estimator in a first mode, the combiner is controlled such that the one of the first power estimator or the second power estimator is an inactive power estimator and the other is an active power estimator, and the combiner is controlled such that it generates the estimated signal power using a function of an output of the active power estimator.

A Radio Frequency, RF, communications device. The device includes a pair of antenna terminals, which are connectable to an antenna. The device also includes an automatic gain controller, which is coupled to the antenna terminals for receiving an output current of the antenna. The automatic gain controller is operable to convert the output current of the antenna into a modulated current. The device further includes a rectifier, which is coupled to the automatic gain controller to receive the modulated current. The rectifier is operable to convert the modulated current into a rectified current. The device also includes a voltage limiter, which is coupled to the rectifier for receiving the rectified current. The voltage limiter is operable to convert the rectified current into a limited rectified voltage for supplying power to the RF communications device. An RFID tag comprising the RF communications device is also disclosed.

A method (100) for a multi-antenna transmitter and receiver arrangement, MATARA, (300), the MATARA (300) comprising two or more antennas (301, 302,..., 316), two or more transceiver front ends (320, 321,..., 328) each comprising two or more transceivers, and two or more automatic gain controllers, AGCs, (330, 331,..., 338) and wherein the MATARA (300) is comprisable in a wireless device, WD, (397), the method comprising: receiving (110) a first plurality of radio signals comprising a first signal transmitted from a remote TNode (398, 399); obtaining (120) a signal power estimate for each of the first plurality of radio signals; obtaining (130) information about correlation between characteristics of the radio signals received by the transceivers; grouping (140) transceivers together in groups of transceivers in accordance with the obtained information; and configuring (150) the AGCs in accordance with the obtained signal power estimates and in accordance with the groups of transceivers. Corresponding computer program product, multi-antenna transmitter and receiver arrangement, control unit, wireless device, and chips are also disclosed.