A positioning device for a radio frequency matcher comprises mainly a micro controller, and at least two detecting elements connected to the micro controller. The detecting elements are disposed on electric motors to detect the rotation angles of the electric motors. When the electric motors adjust the positions of the moving pieces of the tuning elements based on the volume of error signals to change the electrical reactance values so that they may approximately meet the requirement of the radio frequency load and that the radio frequency load may achieve a highest possible power, the micro controller may interpret the signals of the rotation angle detecting elements and output the interpreted values for a user to determine whether the moving pieces of the tuning elements are at right positions to approximately meet the requirement of the radio frequency load and maximize the power of the radio frequency load of the radio frequency matcher.

Provided are an RFID tag information reading apparatus and method, including a signal management circuit, configured to output an operation frequency signal; a resonant circuit, configured to receive the operation frequency signal, adjust a capacitance value and an inductance value of the resonant circuit according to the operation frequency signal, so that the resonant circuit generates a resonance for generating a sine wave signal at a frequency point of the operation frequency signal, the resonant circuit is further configured to generate an electromagnetic wave from the sine wave signal, radiate the electromagnetic wave to a tag, and trigger the tag to return a tag identity signal; and a decoding identification circuit, configured to identify tag information according to the tag identity signal returned by the tag; where the signal management circuit is connected with the resonant circuit, and the resonant circuit is connected with the decoding identification circuit.

Provided are an RFID tag information reading apparatus and method, including a signal management circuit, configured to output an operation frequency signal; a resonant circuit, configured to receive the operation frequency signal, adjust a capacitance value and an inductance value of the resonant circuit according to the operation frequency signal, so that the resonant circuit generates a resonance for generating a sine wave signal at a frequency point of the operation frequency signal, the resonant circuit is further configured to generate an electromagnetic wave from the sine wave signal, radiate the electromagnetic wave to a tag, and trigger the tag to return a tag identity signal; and a decoding identification circuit, configured to identify tag information according to the tag identity signal returned by the tag; where the signal management circuit is connected with the resonant circuit, and the resonant circuit is connected with the decoding identification circuit.

An impedance tuning circuit includes a first node and a second node, and an inductance circuit including an inductor and a first switch connected in series such that the inductor is connected to the first node and the first switch is connected to the second node. The inductance circuit further includes a second switch implemented between ground and a third node between the inductor and the first switch, such that the inductance circuit is capable of providing a series inductance path between the first and second nodes or a shunt inductance path between the third node and the ground.

A method includes generating a calibration signal by a clock generator, feeding the calibration signal to a first filter through a first switch unit, comparing an output of the first filter with the calibration signal through a frequency detector and a phase comparator and generating a first updated bandwidth code to adjust a bandwidth frequency of the first filter.

In accordance with an embodiment, an RF system includes a transmit path having a first tunable transmit band stop filter, and a power amplifier coupled to an output of the first tunable transmit band stop filter, where the first tunable transmit band stop filter is configured reject a receive frequency and pass a transmit frequency; a receive path comprising an LNA; and a duplex filter having a transmit path port coupled to an output of the power amplifier, a receive path port coupled to an input of the LNA, and an antenna port, where the duplex filter is configured to pass the transmit frequency and reject the receive frequency between the antenna port and the transmit path port, pass the receive frequency and reject the transmit frequency between the antenna port and the receive path port.

The invention provides a carrier frequency offset processing method, an apparatus and a receiver. The method comprises: receiving, through a software and hardware interface, an estimated value of frequency offset of a data packet transmitted by an automatic frequency offset control module; collecting the received estimated value of frequency offset of the data packet and performing statistical analysis to obtain a statistical value of carrier frequency offset between a receiving module and a transmitting module; and dynamically adjusting, according to the statistical value of carrier frequency offset, a bandwidth of a low-pass filter through the software and hardware interface. The invention realizes dynamic adjustment of the bandwidth of the low-pass filter in the process of a receiver receiving signals, solving the problem of the impact on processing performance brought by the fixed bandwidth of a low-pass filter in the prior art.

High power impedance tuners suffer from intense heating of the center conductor of the tuner airline (slabline), due to dissipated RF and DC power and, in addition to high electric field between the metallic tuning probe (slug) and the center conductor, also from associated thermal expansion causing sagging of the center conductor and possible electrical short. If the thermal expansion cannot be accommodated by structural means, the center conductor is cooled using forced air created by ventilators or re-circulating low loss dielectric liquid flowing through the slabline. Premature tuner aging through continuous airflow or cooling liquid circulation is avoided using real time monitoring of dissipated (heating) power and regulation of the cooling mechanism.

Systems and methods for performing automatic frequency control are provided. Instead of relying on individual frequency tuners for each channel of a multi-channel receiver system, the present subject matter uses a single frequency tuner for receiving each channel of the multi-channel receiver system. A locked demodulator may be designated as a reference demodulator and frequency offset values associated with the reference demodulator may be applied to other demodulators of the multi-channel receiver. These frequency offset values may be used by individual demodulators of each channel for correcting corresponding frequency offsets.

In some examples, one or more processors configured by executable instructions may receive an audio signal and data to embed in the audio signal. For example, the data may be received dynamically from one or more data sources. The one or more processors may embed the received data in real time into the audio signal as embedded data based at least in part on controlling a phase angle of a selected frequency component of the audio signal. For instance, the embedded data may include at least one of text, a bar code, a quick response code, an image, a uniform resource locator (URL), or multimedia content. Additionally, the one or more processors may send the audio signal with the embedded data over a network to a plurality of electronic devices that include respective decoders for extracting the embedded data from the audio signal.