Abstract: The audio signals associated with different co-located groups of talkers in a teleconference are detected (e.g., by comparing the voiceprint for the current talker group with stored voiceprints corresponding to all of the co-located teleconference participants) and processed using different and appropriate automatic gain control (AGC) levels, where each group has a corresponding stored AGC level. Depending on the embodiment, each group may have one or more participants.

Abstract: In a wireless 802.15.4 communication system, a method and system are provided for switching between a predetermined protocol transmission mode and a high-speed transmission mode by including signaling mode information in a data packet (330, 340) to instruct the receiver device (300) to demodulate at least a data payload using the predetermined transmission mode if the signaling mode information comprises a first predetermined value, and to demodulate at least the data payload using the high-speed transmission mode if the signaling mode information comprises a second predetermined value. The signaling mode information may be included in the SFD field of an 802.15.4 SHR structure to instruct the receiver how to demodulate or process the data packet, or may be included as desired anywhere in the data packet to instruct the receiver how to demodulate or process one or more subsequent data packets.

Abstract: A method for transmitting control information to indicate a receiver, comprising following steps: the control information is formed at transmitting side and is encoded based on the working status of the transmitting side of the system; after the encoded control information is mapped, it is multiplexed with other pilot symbol and service load, then an OFDM symbol is generated; the OFDM symbol is transformed from frequency domain to time domain, then a time domain sampling signal is obtained and transmitted to the receiving side of the system; at the receiving side, the time domain sampling signal transmitted by the transmitting side is received and transformed from time domain to frequency domain to form OFDM symbol; the control information is obtained from the valid sub carrier of the OFDM symbol, and the control information is decoded; each work information is extracted form the decoded control information, and the receiving terminal is indicated to execute respective receive process based on the extracted w

Abstract: Disclosed herein is an iterative process for calibrating an AGC in a wireless system, wherein the iterative process comprises transmitting a calibration signal, receiving the calibration signal, decoding the calibration signal to produce a measurement, storing the measurement and changing an AGC gain setting.

Abstract: A diversity receiver includes a first radio frequency (RF) receiver section receives a first inbound RF signal over a range of frequencies and generates a first amplified RF signal, wherein the first inbound RF signal includes a desired RF signal component and an undesired signal component. A second RF receiver section receives a second inbound RF signal over the range of frequencies and generates a second amplified RF signal, wherein the second inbound RF signal includes the desired signal component and the undesired signal component. A first RF cancellation module generates a desired RF signal from the desired RF signal component while attenuating the undesired signal component, based on the first amplified RF signal and the second amplified RF signal.

Abstract: Provided is an apparatus for automatic gain control (AGC) widely used in a receiver of a wireless communication system. The receiver of a wireless communication system includes: a step variable gain amplifier and an analog variable gain amplifier disposed in the path of a wireless signal and amplifying the wireless signal; an analog gain control unit for generating a gain control voltage for feedback-controlling an amplification value of the analog variable gain amplifier; a digital gain control unit for receiving the control voltage and generating a digital code determining an amplification value of the step variable gain amplifier. The apparatus for AGC constituted as described above can reduce power consumption and the number of devices by efficiently running an AGC loop in an analog domain, and can be embodied at low cost in a structure appropriately controlling the step gain amplifier and the analog gain amplifier.

Abstract: A satellite navigation device including a flexible radio frequency (RF) receiver is described. The receiver receives a signal that includes at least a first spread-spectrum signal from a first satellite. The receiver has a first channel that includes an analog-to-digital (A/D) converter to sample and quantize the signal and an automatic gain control (AGC) to adjust an amplification of the signal. The A/D converter has a first non-zero quantization threshold magnitude and a second non-zero quantization threshold magnitude. The AGC may adjust a gain in accordance with the first non-zero quantization threshold magnitude. The gain may correspond to a first pre-determined probability of a non-zero sample and the second non-zero quantization threshold magnitude may correspond to a second pre-determined probability of a non-zero sample.

Abstract: An RF transceiver includes a plurality of RF receivers for receiving a corresponding one of a plurality of received signals. Each of the plurality of the RF receivers includes an AGC module that generates an automatic gain control (AGC) signal based on the strength of the corresponding one of the plurality of received signals, and a low noise amplifier that amplifies the corresponding one of the plurality of received signals based on the AGC signal. A processing module generates a transmit power control signal based on the AGC signals from each of the plurality of RF receivers. A plurality of RF transmitters each generate a corresponding one of a plurality of transmit signals having a selected power level, wherein the selected power level is based on the transmit power control signal.

Abstract: An RF transceiver includes an RF receiver that receives a received signal from an external device, the RF receiver having an AGC module that generates an automatic gain control (AGC) signal based on a strength of the received signal, and a low noise amplifier that amplifies the received signal based on the AGC signal. A processing module generates a transmit power control signal based on the AGC signal. An RF transmitter generates a transmit signal having a selected power level, wherein the selected power level is based on the transmit power control signal.

Abstract: In RF transceivers, a method and system for a second order input intercept point (IIP2) correction are provided. A DC offset sensor may detect DC offset voltages produced by blocker signals in “I” and “Q” signal component paths in an RF receiver. The DC offset sensor may generate control signals which may be utilized by a first and second injection circuits to generate DC offset currents that compensate for the DC offset voltages in the signal component paths. An injection circuit may utilize current drivers to generate binary weighted currents which may be added together to produce a DC offset current. The polarity of the DC offset current and the selection of which current drivers to use may be determined by the control signals. A calibration voltage may also be utilized to correct or adjust the gain in the injection circuit.

Abstract: A symbol clock recovery subsystem uses a tap delay line having a set of delays, uses a clock bank of samplers providing time-staggered sampled noncoherently received signals, and uses a set of mean magnitude generators, in channelized form, for providing a set of mean magnitudes to a maximum selector for selecting a maximum one of the time-staggered sampled received signals having the greatest signal to noise ratio so as to provide a signal effectively occurring at symbol epoch time for demodulating a symbol stream in a digital communication system receiver.

Abstract: A fast settling AGC system includes a “fast settle” comparator that facilitates fast settling of strong radio receiver output signals from a maximum to an intermediate voltage level at the start of each transmission burst, and a “normal” AGC comparator that further settles the output signal from the intermediate voltage level to a desired target output voltage level at a slower “normal” rate. The gain control signal components generated by both the “fast settle” comparator and the “normal” AGC comparator are summed and applied to the gain control terminal of a variable gain amplifier. The gain control signal component generated by the “fast settle” comparator has a higher current level than the gain control signal component generated by the “normal” comparator, but is terminated when receiver output signal drops to the intermediate voltage level.

Abstract: A signal relay apparatus, method, application program, and computer readable medium adapted for wireless network are capable of saving power consumption due to failure of adjusting amplifying gain dynamically and solving the difficulty of demodulation since noise is also amplified during relay. For wireless access network, the present invention decreases the transmission power of mobile devices so that the battery of the mobile devices may keep working longer and the interference inside is reduced.

Abstract: A method includes a foreground process and a background process. In the foreground process, an input signal is processed using a first reference signal to generate an output. A first frequency control signal is generated from the output. A frequency of the first reference signal is controlled based on the first frequency control signal. In the background process, a foreground processed signal is received from the foreground process. The foreground processed signal is processed using a second reference signal. A second frequency control signal is generated from the foreground processed signal. A frequency of the second reference signal is controlled based on the second frequency control signal so that the background processing step removes effects of the foreground controlling step.

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: The demodulator in the receiving module of the invention supplies a signal produced based on a signal level detected by a first detector to a second amplifier as an amplification degree adjustment signal. With this arrangement, when a second receiver works, an AGC voltage supplied to the second receiver is already close to an ultimately converging certain value. The AGC voltage supplied to the second receiver is thus stabilized in its value, from the value close to the ultimately converging certain value to the certain value. Accordingly, a time period required from the second receiver starts working until the AGC voltage supplied to second amplifier ultimately converges into the certain value is shortened.

Abstract: An integrated circuit (IC) includes a plurality of RF receivers for receiving a corresponding one of a plurality of received signals. Each of the plurality of the RF receivers includes an AGC module that generates an automatic gain control (AGC) signal based on the strength of the corresponding one of the plurality of received signals, and a low noise amplifier that amplifies the corresponding one of the plurality of received signals based on the AGC signal. A processing module generates a power mode signal for adjusting a power consumption parameter of the IC, based on the AGC signals from each of the plurality of RF receivers.

Abstract: An integrated circuit (IC) includes an RF receiver having an AGC module that generates an automatic gain control (AGC) signal based on a strength of a received signal, and a low noise amplifier that amplifies the received signal based on the AGC signal. A processing module generates a power mode signal based on the AGC signal, the power mode signal for adjusting a power consumption parameter of the IC based on the power mode signal.

Abstract: Whether the reception electric field level of the antenna #1 is higher than the predetermined level is judged. If the reception electric field level of the antenna #1 is not higher than the predetermined level, the communication mode is to be set to the multi-slot mode, and then whether the reception electric field level of the antenna #1 is higher is judged by comparison of the reception electric field level of the antenna #1 and the reception electric field level of the antenna #2. If the reception electric field level of the antenna #1 is higher, the call mode is to be set to the antenna #1 for executing transmission and reception, or if the reception electric field level of the antenna #1 is not higher, the communication mode is to be set to the antenna #2 for executing transmission and reception.

Abstract: Described herein is a method of automatic gain control and simultaneous digital correction of three types of variations in I/Q receivers: gain imbalance, phase imbalance, and DC offset. Three adaptation loops can operate simultaneously and use the output of an analog to digital converter (ADC) as their input, with the output driving digitally controllable analog components. With appropriate knowledge of signal statistics, the algorithm automatically optimally fills the ADC's full input signal range, providing an automatic gain control function and thus maximizing the signal-to-quantization-noise ratio. In so doing, it corrects gain imbalances between I and Q paths, while additional circuitry corrects DC offsets and phase imbalances.

Abstract: An antenna (8), mounted to a roof (3) of a building (1), receives digital broadcast transmissions and feeds a signal through a cable (9) to a desk stand (2). The desk stand has an amplifier and a loop antenna. A mobile telephone handset (6) capable of receiving digital broadcast transmissions also includes a loop antenna. Using inductive coupling, the signal is transmitted from the desk stand to the mobile telephone handset.

Abstract: Techniques are disclosed for detecting a packet. One technique includes sampling a received signal to produce a sequence of samples wherein the sequence of samples includes a plurality of subsequences of samples; cross correlating the subsequences of samples with a known form of the subsequence to produce cross correlations; self correlating the cross correlations to produce a plurality of self correlations; summing the self correlations; and processing the sum of the self correlations.

Abstract: A radio frequency (RF) transceiver integrated circuit (IC) includes a plurality of baseband Tx sections, a plurality of RF Tx sections, a plurality of RF Rx sections, and a plurality of baseband Rx sections. The RF transceiver IC further includes a static digital interface, a dynamic digital interface, and gain control, distribution, and buffering circuitry. Static digital interfaces are operable to receive static gain control commands from a coupled baseband processor. The dynamic digital interface is also operable to receive dynamic gain control commands from the coupled baseband processor. The gain control, distribution, and buffering circuitry is operable to apply the static gain control commands and dynamic gain control commands to at least some of the plurality of baseband Tx sections, the plurality of RF Tx sections, the plurality of RF Rx sections, and the plurality of baseband Rx sections.

Abstract: A method and apparatus for operating a radio reception system, which comprises a plurality of receivers assigned to a common output device, in which one of the receivers is designated as audio receiver and is tuned to a frequency of a radio transmitter, and outputs a signal received from the transmitter to the output device. At least one second receiver is designated as search receiver, and continuously searches its own reception frequency band for a frequency of the same transmitter. The system changes to a frequency of this transmitter, which was found by the search receiver, if the quality of the signal received by the audio receiver falls below a certain limit.

Abstract: A MIMO wireless system includes a transmitter having a parser that parses a bit stream into multiple spatial data streams and multiple interleavers corresponding to the multiple spatial data streams, where each interleaver interleaves the bits in the corresponding spatial data stream by performing multiple column rotations and row rotation, to increase diversity of the wireless system. The MIMO wireless system also includes a receiver that has deinterleavers that deinterleaves spatial bit streams transmitted by the transmitter.

Abstract: A wireless telecommunication device, a method of frequency calibrating a wireless telecommunication device, and a computer program are provided. The method comprises: receiving a reference radio signal of the wireless telecommunications system; frequency synchronizing the wireless telecommunication device with the reference radio signal by adjusting a control parameter controlling a reference frequency generated by a reference frequency generator; measuring a temperature parameter characterizing the temperature of the reference frequency generator; and generating calibration information for calibrating the wireless telecommunication device on the basis of the control parameter and the temperature parameter.

Abstract: A RAKE receiver is adapted to receive input from at least a first and a second antenna (104a, 104b). The RAKE receiver comprises a despreading unit (303) adapted to allocate a number (Nf) of despreading fingers to a number of delay positions of a signal which is transmitted over a channel. The RAKE receiver further comprises a delay position selection unit (305) which estimates an antenna correlation (formula 1) between the at least first and second antenna (104a, 104b) and controls the despreading unit (303) according to a first strategy for allocating the number (Nf) of fingers if the antenna correlation (formula 1) is below a predetermined threshold, and according to a second strategy otherwise. The threshold (formula 2) is selected based on at least one of the following: number of available finger in the RAKE receiver (Nf), dispersion of the channel, range of direction of arrivals (??).

Abstract: A technique includes generating an analog voltage to control a frequency for an oscillator. The analog signal is converted into a digital signal, and the frequency is controlled in response to the digital signal.

Abstract: An automatic gain control (AGC) method according to the present invention applies an initial gain by a digital AGC circuit in a timeslot is determined using a final calculated gain from the same timeslot in the previous frame together with an offset factor. An erase function is activated for a given data sample block when the number of saturated data samples that are detected within the block exceeds a threshold value. The power measurement made by the AGC circuit and used to update the gain is adjusted based on the number of measured data samples that are saturated. These elements provide a gain limiting function and allows limiting of the dynamic range for further signal processing.

Abstract: An apparatus for controlling transmission power of a mobile communication terminal. The apparatus comprises a central processing unit for measuring a power level of a received signal and determining a power amplification mode in response to the measured power level of the received signal and a power preset table, a driver amplifier for amplifying a transmission signal to produce an output signal, the driver amplifier has operating conditions chosen in accordance with the power amplification mode, a voltage converter for outputting a preset voltage value in accordance with the power amplification mode, and a power amplifier for amplifying the output signal of the driver amplifier in response to the outputted preset voltage value.

Abstract: A tuner down-converts a Radio Frequency (RF) wireless signal and outputs the converted signal. The tuner compensates for a TOP depending on a temperature and: detects a received signal strength depending on a RF output of the tuner and transmitting the detected strength to a gain control unit; measures an operating temperature of the tuner and transmits the measured temperature value; receives the measured temperature value to compare the received temperature value with a reference TOP value, compensating compensates for the TOP value depending on variation in temperature and outputting outputs the compensated value; and receives the compensated value to control the RF output based on the TOP value and the received signal strength.

Abstract: A closed-loop antenna switching method, a reference signal allocating method, and a feedback signal transmitting method for the same are disclosed. Namely, by transmitting a reference signal via the plurality of transmitting antennas via the antenna switching for reference signal transmission for each prescribed multiple period of an antenna selection period, efficient antenna index information can be fed back. By setting an antenna switching period to a prescribed multiple of an antenna selection period, it is able to prevent power loss and data decoding performance degradation. And, the present invention includes transmitting a sounding reference signal (SRS) for each band selection period via at least one of the plurality of transmitting antennas and transmitting at least one data demodulation reference signal (DMRS) between the band selection periods via an antenna for not transmitting data by reference signal transmission antenna switching.

Abstract: A dynamic DC offset removal apparatus and a dynamic DC offset removal method capable of accurately estimating a change position of a dynamic DC offset and a DC offset value before the change and a DC offset value after the change, thereby carrying out equalization processing on a reception signal whose dynamic DC offsets are removed, and improving a bit error rate characteristic.

Abstract: A method for operating a power controller in a wireless communication device is provided that includes generating a power controller output signal using an open loop polar modulation scheme. The power controller output signal is operable to control the power delivered to a high-band power amplifier and a low-band power amplifier. A band state is determined for the wireless communication device. The power controller output signal is provided to the high-band power amplifier when the band state is a high-band state and to the low-band power amplifier when the band state is a low-band state.

Abstract: Digital autonomous AGC for a DVB-H receiver comprises detecting a plurality of RF signals entering a LNA in the DVB-H receiver; detecting a RF transmitter blocker signal occurring at the LNA; and differentiating between a desired RF signal and an undesired RF transmitter blocker signal by varying a differential gain of current through the LNA. A RF servo loop is used for detecting the RF transmitter blocker signal. Logic circuitry of the RF servo loop is integrated with a baseband AGC loop to step control the differential gain of current through the LNA. A RF wideband detector is used for detecting the plurality of RF signals entering the LNA; and sending a voltage output corresponding to voltage levels of the RF signals to a plurality of comparators, wherein each of the plurality of comparators are set at a different programmable voltage threshold level compared with one another.

Abstract: The invention provides a radio frequency signal receiver with adequate gain control path to control the gain of a mixer and/or a channel selection filter, comprising a low noise amplifier for receiving and amplifying a radio frequency signal, a local oscillator (LO) for providing a LO signal, a mixer for down converting the radio frequency signal by the LO signal to an intermediate signal, a channel selection filter for receiving and filtering the intermediate signal to develop an output signal, and an automatic gain control unit for feedback adjusting the gain of the low noise amplifier and forward controlling the gain of the mixer and channel selection filter in accordance with the output signal of the low noise amplifier.

Abstract: A diversity receiver includes: a plurality of demodulating means for demodulating inputted OFDM signals, to output their demodulated signals; noise component calculating means provided for each demodulating means, for calculating noise components included in the demodulated signals outputted from corresponding demodulating means; channel profile calculating means provided for each demodulating means, for calculating channel profiles based upon the demodulated signals outputted from corresponding demodulating means; transmission channel decision means for determining transmission channel based upon the channel profiles; reliability information generating means for generating reliability information indicating reliability of the demodulated signals outputted from each demodulating means, based upon the noise components and the results of the determinations by the transmission channel decision means; a weighting factor calculating means for calculating, depending on the reliability information, weighting factors

Abstract: A single-path enhanced-algorithm digital automatic gain control (SDAGC) integrated receiver is presented. The SDAGC has a front-end RF/IF reception/processing block and associated RF/IF AGC, which outputs to a single ADC. Output from the ADC is split into two TDM and one COFDM signal pathways, each with a respective DAGC. The TDM DAGCs are controlled according to TDM post-power signals, while the COFDM, DAGC is controlled according to COFDM post- and pre-power signals. An IF Gain Decision block determines the RF/IF gain based upon the respective gains of the TDM and COFDM DAGCs. A Gain Distributor block then distributes the total gain of the system across the RF/IF AGC and the various DAGCs. To save power, the COFDM pathways may be disabled if the COFDM pre-power signal falls below a threshold value.

Abstract: A variable gain amplifier (VGA) circuit and an automatic gain control (AGC) method thereof are disclosed. The VGA circuit includes an amplifier circuit and an AGC circuit. The amplifier circuit amplifies an input signal to an output signal according to a predetermined gain and the AGC circuit is connected to the amplifier circuit for regulating the predetermined gain. The AGC circuit further includes a peak detector detecting a peak of the output signal, a replica of the peak detector for detecting a peak of a reference signal, and a comparator for comparing the peak of the output signal with the peak of the reference signal to provide a control signal and then providing the control signal to the amplifier circuit to regulate the predetermined gain.

Abstract: When power to be transmitted varies, a control section instructs an AGC control section to control a gain of an IQ modulation processing section 6 in accordance with the power. A switch selects a power source voltage, corresponding to the power to be transmitted, from power source voltages V1 to V3 of a wireless module, in accordance with an instruction of the control section, so as to supply thus selected power source voltage to a power amplifier. Thus, it is possible to realize a wireless communication circuit which occupies a less area and consumes smaller amounts of power without narrowing a communication range.

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: An apparatus comprises a link interface to receive an OFDM symbol from a communications link. A signal-to-noise ratio estimation unit generates an estimate of a geometric signal-to-noise ratio for the received symbol based on a function of the soft and hard decisions. A signal quality of the wireless communications link is based on the geometric signal-to-noise ratio.

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 GPS receiver circuit (300) for reducing insertion loss. The receiver circuit (300) includes a switch (304) for diverting input signals between a filtered pathway (312) and a short circuit pathway (310) to an amplifier (314). The amplifier (314) output feeds an automatic gain controller (316) that senses a noise level in the output of the amplifier (314) and adjusts a gain of the amplifier (314) in response to the noise level. The receiver circuit (300) also includes a threshold detector (306) with an input coupled to the output of the automatic gain controller (316) and an output coupled to the switch (304) for selecting between the filtered pathway (312) and the short circuit pathway (310), thereby removing the filter (312) from the signal path if not needed.

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: According to various exemplary embodiments, apparatus, systems, and methods are disclosed for use with antenna systems operable for receiving first and second signals having respective first and second frequencies. In one exemplary embodiment, a controller selectively controls whether an amplifier is electrically powered via a first receiver associated with the first frequency or a second receiver associated with the second frequency depending on whether the first receiver, second receiver, or both are present and activated.

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: A tuner, a broadcast signal processing apparatus and method, which satisfy reception sensitivity of both terrestrial and cable televisions, when selecting a broadcast signal through a single conversion tuner, are provided. A tuner selects a broadcast signal of a selected channel. The tuner includes an input filter that filters a received broadcast signal into plural frequency bands based on a predetermined frequency band. An amplifier amplifies a second signal having an original phase induced by an output signal of the respective frequency bands, and a first signal having an opposite phase of the second signal, and outputs the signal induced by the amplified first and second signals as an amplification signal of the signal in the respective frequency bands. An inter-stage filter filters a frequency of the broadcast signal corresponding to the selected channel among the amplification signals output from the amplifier.

Abstract: A receiver 30 has an adjustable gain control circuit 32 that provides gain control base on the magnitude of the signal at the input of an analog-to-digital converter 22. The magnitude of a gain increase or decrease can be based on the most significant bits of the analog-to-digital output, indicating whether the analog-to-digital converter is close to saturation, approaching saturation, or well below saturation.

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.