Abstract: Disclosed is a radio frequency (RF) receiver for receiving a communication channel modulated on one or more carrier frequencies. The receiver may include a gain adjustable RF amplifier, a wideband signal power measurement circuit, and control logic. The control logic may be adapted to use outputs of one or more measurement circuits to classify interfering signals based on measured signal power and spectral proximity to the one or more channel carrier frequencies, and to adjust the gain of the radio frequency amplifier based on the classification.

Abstract: A mechanism can be implemented for reducing the power consumption of a wireless radio device in establishing a wireless connection by utilizing a wideband signal to detect a narrowband trigger signal at a potential narrowband trigger frequency. The wireless radio device may operate a wideband receiver to receive an RF signal. Being aware of the potential narrowband trigger frequencies, the wideband receiver may utilize the received RF signal to detect the presence of a narrowband trigger signal at one of the potential narrowband trigger frequencies.

Abstract: A system and technique for providing to flexible, programmable frequency estimators and spectrum analyzers that can operate over extremely large bandwidths and yet provide high spectral resolution are described. The system and technique may include a cascaded super-heterodyne apparatus for estimating a frequency and a bandwidth of signals proximate in frequency to a desired signal, a tunable filter coupled to an input of a receiver, and a tuner which receives a signal from said cascaded super-heterodyne apparatus and tunes the filter to filter out unwanted signals from the receiver.

Abstract: The invention teaches a solution, for example, for Long Term Evolution (LTE) networks. The solution comprises determining a measurement pattern for at least one automatic gain control tracking loop when resource restrictions have been configured for a user equipment, the resource restrictions comprising at least one measurement restriction pattern, wherein each automatic gain control tracking loop is associated with at least one measurement restriction pattern; and performing automatic gain control measurements according to the measurement patterns of the at least one automatic gain control tracking loop.

Abstract: In an oscillating apparatus, a detection unit detects a frequency offset between an input signal and a reference signal. A code generation unit specifies a relationship among a code having a predetermined number of bits, the frequency offset, and a voltage to be applied to a voltage-controlled oscillator by a DAC, in accordance with a frequency offset detection state of the detection unit. The code generation unit also generates a frequency offset correction code having a predetermined number of bits in accordance with the specified relationship. The DAC applies the voltage to the voltage-controlled oscillator, in accordance with the relationship described above and the code generated by the code generation unit. The voltage controlled oscillator outputs an oscillator signal having an oscillation frequency corresponding to the voltage applied by the DAC.

Abstract: A broadcast receiving apparatus includes a first tuner configured to receive a broadcast wave from a specified broadcasting station, a second tuner configured to perform a frequency search for receivable broadcasting stations, a power supply unit configured to supply power to the first tuner and the second tuner, a traveling state detection unit configured to determine if a vehicle is moving or is stopped, a reception state detection unit configured to detect a reception state of a currently-received broadcast wave, and a control unit configured to control the first tuner, the second tuner, the power supply unit, the traveling state detection unit, and the reception state detection unit.

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 receiver suppresses noise simultaneously using a noise suppressor and an automatic gain controller (AGC). The receiver divides a received signal into an audio period and a non-audio period, analyzes whether the noise characteristic of the non-audio period corresponds to a non-static noise or a static noise, and if the noise characteristic corresponds to the static noise, analyzes whether the static noise is caused by a network or a transmitter side terminal. In accordance with the analyzed noise characteristic, the noise suppressor firstly suppresses the noise by determining the noise suppressing intensity, and sends a signal, from which the noise has been firstly suppressed, to the AGC. The AGC secondly suppresses the noise included in the signal. In this case, the threshold value of the AGC is controlled in real time in accordance with the noise characteristic.

Abstract: An automatic gain control circuit is described including a state machine controller for adjusting intermediate frequency gain and radio frequency gain and a baseband demodulator, wherein the baseband demodulator receives information from the state machine controller regarding status of the state machine controller and further wherein the state machine controller receives correlation information from the baseband demodulator. Also described is a method including detecting a signal, providing state machine controller information to a baseband demodulator, reducing a radio frequency gain, reducing an intermediate frequency gain and receiving correlation information from the baseband demodulator.

Abstract: Systems and methods are provided for enhancing signal quality at receivers in a wireless network. In one embodiment, an antenna is selected from a subset of antennas based on a signal quality parameter such as received signal power or signal-to-noise ratio (SNR). In another embodiment, multiple antennas are applied to independent signal processing paths for the respective antennas where output from the paths is then combined to enhance overall signal quality at the receiver.

Abstract: Apparatus and systems, as well as methods and articles, may operate to enter an idle state of a wireless device for a selected amount of time responsive to a combined clear channel assessment indication.

Abstract: Aspects of a method and system for channel estimation in a MIMO communication system with multiple RF chains for WCDMA/HSDPA may comprise receiving a plurality of communication signals from a plurality of transmit antennas. A plurality of vectors of baseband combined channel estimates may be generated based on phase rotation of the received plurality of communication signals. A matrix of processed baseband combined channel estimates may be generated based on the generated plurality of vectors of baseband combined channel estimates. A plurality of amplitude and phase correction signals may be generated based on the generated plurality of vectors of baseband combined channel estimates. An amplitude and a phase of at least a portion of the received plurality of communication signals may be adjusted based on the generated plurality of amplitude and phase correction signals, respectively.

Abstract: Circuits, architectures, a system and methods for providing on-chip gain calibration. The circuit generally includes a receiver comprising (i) a resistor on a semiconductor substrate, the resistor configured to provide a signal having a noise component that varies with temperature, and (ii) an amplifier circuit on the semiconductor substrate coupled to the resistor, the amplifier circuit configured to receive the signal and provide a second signal having an amplitude greater than the first signal. The architectures and/or systems generally include those that embody one or more of the inventive concepts disclosed herein. The method generally includes (i) providing a noise signal from a resistor to an amplifier, the resistor being on a common semiconductor substrate with the amplifier, (ii) determining a resistance value of the resistor, (iii) determining an impedance at an input of the amplifier, and (iv) determining a gain of the amplifier.

Abstract: A clock signal generating arrangement for a communication device generates a system clock signal at an output for use as a timing reference. The clock signal generating arrangement comprises a reference clock generator for generating a reference clock signal, a main clock generator for generating a main clock signal having a greater accuracy than the reference clock signal, a clock adjust circuit coupled to the reference clock generator for generating a compensated reference clock signal to compensate for error in the reference clock signal and a clock signal selector coupled to the reference clock generator the main clock generator and the clock adjust circuit.

Abstract: Techniques for performing frequency control using dual-loop automatic frequency control (AFC) are described. The dual-loop AFC includes an inner loop that corrects short-term frequency variations (e.g., due to Doppler effect) and an outer loop that corrects long-term frequency variations (e.g., due to component tolerances and temperature variations). In one design, a first inner loop is implemented for frequency control of a first system (e.g., a broadcast system), a second inner loop is implemented for frequency control of a second system (e.g., a cellular system), and at least one outer loop is implemented for adjusting a reference frequency used to receive signals from the first and second systems. Each inner loop estimates and corrects the frequency error in an input signal for the associated system and may be enabled when receiving the input signal from the system. The reference frequency may be used for frequency downconversion, sampling and/or other purposes.

Abstract: A system and method provide adaptive filtering of radio frequency (RF) signals. Multiple signals are received in a predetermined RF spectrum, the signals including a desired signal and multiple potentially interfering signals. A first signal of the potentially interfering signals is down-converted to a baseband signal, and a power of the baseband signal is determined. When the power exceeds a predetermined threshold power, a first notch filter, corresponding to a frequency of the first signal, is activated.

Abstract: A clipping detection device calculates an amplitude distribution of an input signal for each predetermined period, calculates a deflection degree of the distribution on the basis of the calculated amplitude distribution, and then detects clipping of a communication signal on the basis of the calculated deflection degree of the distribution.

Abstract: Methods and systems for processing signals in a receiver are disclosed herein and may comprise receiving spatially multiplexed signals via M receive antennas. A plurality of multiple data streams may be separated in the received spatially multiplexed signals to detect MIMO data streams. Each of the MIMO data streams may correspond to a spatially multiplexed input signal. Complex phase and/or amplitude may be estimated for each detected MIMO data streams utilizing (M-1) phase shifters. Complex waveforms, comprising in-phase (I) and quadrature (Q) components for the MIMO data streams within the received spatially multiplexed signals may be processed and the processed complex waveforms may be filtered to generate baseband bandwidth limited signals. Phase and/or amplitude for one or more received spatially multiplexed signals may be adjusted utilizing the estimated complex phase and amplitude. Phase and/or amplitude may be adjusted continuously and/or at discrete intervals.

Abstract: An antenna system for receiving an RF signal from a first antenna and a second antenna includes a phase shift circuit. The phase shift circuit shifts a phase of the RF signal from the second antenna by one of a plurality of possible phase shifts to produce a phase shifted signal. A combiner combines the RF signal from the first antenna and the phase shifted signal to produce a combined signal. A comparator circuit compares a signal quality of the combined signal with a minimum threshold value to determine if the signal quality of the combined signal is equal to or greater than the threshold value. The comparator circuit is in communicative control of the phase shift circuit and maintains the phase shift of the RF signal received by the second antenna in response to the signal quality of the combined signal being equal to or greater than the threshold value.

Abstract: According to an embodiment, a DC offset canceller includes a first DA converter, a first adder, an amplifier, a comparator, an averaging circuit, and a successive approximation register. The first DA converter is configured to DA-convert first correction data into a first correction voltage. The first adder is configured to add an input signal and the first correction voltage to output a first added signal. The amplifier is configured to amplify the first added signal to output an amplified signal. The comparator is configured to compare the amplified signal and a reference voltage to output a comparison result. The averaging circuit is configured to receive the comparison results of the comparator to obtain a majority decision result by performing majority decision on logical values of the comparison results in a predetermined time period.

Abstract: A method, apparatus, and computer program for controlling diversity reception in a radio receiver are provided. The radio receiver is configured to either activate or disable the diversity reception according to an application type of an application requesting transfer of data.

Abstract: The return channel in a multiple-input and multiple-output (MIMO) communication system is used to provide signal information on an individual-channel basis. In one embodiment, in a controlled factory environment, this information may be used to incrementing up or down the variable gain amplifier and/or the power amplifier of a MIMO transmitter and/or receiver so as to generate a default signal power offset to be used during normal operation. Thereafter, such signal information may similarly be provided via the return channel and used to further adjust the transmit parameters to account for location-specific signal conditions.

Abstract: A wireless telecommunications system for stationary or semi-stationary equipment includes a main node and a first plurality of terminals belonging to the same access subset and arranged to receive from and transmit to the main node. The main node transmits in at least one beam and receives in at least two beams, and the system indicates to the terminals that they may or may not transmit to the central node. Based upon certain criteria, two or more terminals located in different receive beams of the main node may be given permission to transmit to the central node simultaneously. Suitably, two or more terminals which are given permission to transmit simultaneously do so using the same frequency, or the same code, or the same time slot.

Abstract: A method for use in a digital communications receiver for controlling an input signal level (200) into an analog-to-digital converter (ADC) initially receives a sample sequence (201) where a threshold crossing rate is measured as a percentage samples of an input signal that exceed the threshold (203). The error between the measured threshold crossing rate and a desired reference threshold crossing rate is calculated (205) and an error signal is then utilized in a feedback loop to control the receiver gain such that the error is reduced (207).

Abstract: A gaming machine for conducting a wagering game includes a value input device for receiving a wager and a processor for executing gameplay on the gaming machine. The processor has a plurality of power consumption levels. A power regulator is operative to alter the power consumption level of the processor amongst the plurality of power consumption levels. In an embodiment, the power regulator comprises application software stored on a memory device in communication with the processor.

Abstract: A multipath signal determination method includes carrying out correlation operation between a received signal of a positioning signal spread-modulated with a spread code and a replica signal of the spread code with respect to each of IQ components at a predetermined sampling phase interval, and determining whether the received signal is a multipath signal or not, in accordance with a plot position in the case where each correlation value in each of the sampling phases is sequentially plotted on an IQ coordinate.

Abstract: Complex digital data values derived from a DSSS signal, in particular, a GNSS signal, are delivered to a general purpose microprocessor at a rate of 8 MHz and chip sums over eight consecutive data values spaced by a sampling length (TS), each beginning with one of the data values as an initial value, formed and stored. For code removal, each of a series of chip sums covering a correlation interval of 1 ms and each essentially coinciding with a chip interval of fixed chip length (TC), where a value of a basic function (bm) reflecting a PRN basic sequence of a satellite assumes a correlation value (Bm), is multiplied by the latter and the products added up over a partial correlation interval to form a partial correlation sum. The partial correlation interval is chosen in such a way that it essentially coincides with a corresponding Doppler interval having a Doppler length (TD) where a frequency function used for tentative Doppler shift compensation and represented by a step function (sine, cosine) is constant.

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

Abstract: Certain aspects of the method may comprise generating at least one control signal that may be utilized to control at least a first of a plurality of received spatially multiplexed communication signals. An amplitude and/or phase of the first received spatially multiplexed communication signal may be adjusted via the generated control signal so that the amplitude and/or phase of the first received spatially multiplexed communication signal may be equivalent to an amplitude and/or phase of a second received spatially multiplexed communication signal. The amplitude of the first received spatially multiplexed communication signal is adjusted within the processing path used to process the first received spatially multiplexed communication signal.

Abstract: Provided is a measurement apparatus that measures power of an orthogonal frequency division multiplexing modulated signal (OFDM modulated signal) output from a transmitting device, comprising an output control section that causes the transmitting device to output the OFDM modulated signal having a prescribed waveform that repeats in each of a plurality of repetition periods; and a power measuring section that measures, over a measurement period that corresponds to an integer multiple of the repetition period, the power of the OFDM modulated signal output by the transmitting device. The output control section may cause the transmitting device to output the OFDM modulated signal having, as the repetition period, a period for which the arrangement of a pilot signal is the same in a direction of sub-carriers and a direction of OFDM symbols.

Abstract: An apparatus and a method for performing an attenuation function on a signal using an attenuator in a cable broadcast receiver having a Low Noise Amplifier (LNA) that does not perform an attenuation function on a signal are provided. In the method, an input Radio Frequency (RF) signal is tuned, The RF signal is converted into an Intermediate Frequency (IF) signal. An intensity of the converted IF signal is compared to a threshold, and an RF Automatic Gain Control (AGC) value is generated based on a result of the comparison. When the generated RF AGC value is smaller than an RF AGC threshold, the attenuator is turned on to attenuate the input RF signal by a predefined amount. Therefore, a high SNR, such as in an analog-digital composite signal, may be obtained without using an LNA that performs an attenuation function on a signal.

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 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: 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: 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: A frequency error correction scheme applicable in a receiver of a mobile telecommunication system is presented. The present frequency error correction scheme is carried out in a time domain after an equalization process. The present frequency error correction scheme may be applied to a base station receiving signals transmitted according to a single-carrier frequency division multiple access communication scheme. The separation of different received signals for further processing is carried out in the frequency domain before the equalization and the frequency error correction.

Abstract: When a first communication apparatus issues a request for communication quality securement to a control station in order to select communication using a communication path via a control station or communication using a direct communication path between communication apparatuses, it is determined whether the communication partner of the first communication apparatus is a communication apparatus accommodated in the same control station. The control station selects a communication path on the basis of the determination.

Abstract: A signal generation section generates an amplitude signal and an angle-modulated signal. An adaptive compensation filter performs waveform shaping on the amplitude signal in accordance with a magnitude of the amplitude signal. An amplitude amplification section outputs a signal proportional to a magnitude of the signal subjected to waveform shaping in the adaptive compensation filter. An amplitude modulation section amplitude-modulates the angle-modulated signal by the signal outputted from the amplitude amplification section and outputs the resulting signal as a modulated signal. Characteristics of the adaptive compensation filter are inverse characteristics of transfer characteristics from an input of the amplitude amplification section to an output of the amplitude modulation section.

Abstract: A method for configuring a multiple input multiple output (MIMO) wireless communication begins by generating a plurality of preambles for a plurality of transmit antennas. Each of the plurality of preambles includes a carrier detection sequence at a legacy transmit rate, a first channel sounding at the legacy transmit rate, a signal field at the legacy transmit rate, and Z?1 channel soundings at a MIMO transmit rate, where L corresponds to a number of channel soundings. The method continues by simultaneously transmitting the plurality of preambles via the plurality of transmit antennas.

Abstract: An integrated circuit radio transceiver and method therefor is operable to determine an antenna configuration for receive operations. More specifically, the system is operable to determine a receive antenna configuration in a network that includes a number of spatial streams, antenna configuration information, code rate, quadrature modulation type, and transmission protocol modulation scheme, etc. Generally, a selected antenna configuration for transmissions to a remote transceiver is used as an initial antenna configuration for receive operations.

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 portable radio communications device is for transmitting data and voice communications. The portable radio communications device may include a portable housing, a radio transceiver operating at a frequency in a range of 30 MHz-3000 MHz and being carried by the portable housing for direct communication with a corresponding radio transceiver, and a metropolitan area network (MAN) transceiver carried by the portable housing for indirect communication with a corresponding MAN transceiver via a MAN base station. The portable radio communications device may also include a controller carried by the portable housing for selectively allocating transmission of the data and voice communications between the radio transceiver and the MAN transceiver based upon a received signal characteristic. The controller may preferentially allocate the voice communications and the data communications to the radio transceiver and the MAN transceiver, respectively.

Abstract: Aspects of a method and system for channel estimation in a MIMO communication system with multiple RF chains for WCDMA/HSDPA may comprise receiving a plurality of communication signals from a plurality of transmit antennas. A plurality of vectors of baseband combined channel estimates may be generated based on phase rotation of the received plurality of communication signals. A matrix of processed baseband combined channel estimates may be generated based on the generated plurality of vectors of baseband combined channel estimates. A plurality of amplitude and phase correction signals may be generated based on the generated plurality of vectors of baseband combined channel estimates. An amplitude and a phase of at least a portion of the received plurality of communication signals may be adjusted based on the generated plurality of amplitude and phase correction signals, respectively.

Abstract: There is provided a method for generating an error signal for an automatic frequency control (AFC) loop in a Code Division Multiple Access (CDMA) system. Sign information relating to phase differences in received pilot signals is accumulated. In one embodiment, the accumulated sign information is compared against predetermined threshold levels. The error signal is generated when at least one of the predetermined threshold levels is satisfied. In a second embodiment, the accumulated sign information is decimated. An output of the decimating step is utilized as the error signal for the AFC loop.

Abstract: Disclosed herein is an information processing apparatus including: judging means for judging whether a receiving device for receiving a signal amplified by an amplifying circuit which amplifies a supplied signal has a good reception state or not; and control means for changing a power supply voltage of said amplifying circuit to change a gain of the amplifying circuit if said judging means judges that said receiving device does not have a good reception state.

Abstract: In accordance with embodiments of the present disclosure, an information handling system is provided. The information handling system may include a processor; a display coupled to the processor, the display comprising a pixel clock source configured to generate a pixel clock frequency; a memory device coupled to the processor, the memory device having a lookup table stored thereon; and a controller coupled to the processor and configured for: receiving frequency information associated with wireless transmissions of the information handling system; and dynamically adjusting the pixel clock frequency by selecting a frequency from the lookup table in response to a determination that the received frequency information is approximately equal to the pixel clock frequency.

Abstract: The invention relates to a method for setting an operating parameter in a peripheral IC. In this method, the operating parameter is transmitted from a central IC via a bus connection to the peripheral IC. The method is characterized in that the operating parameter is initially buffered in a preregister in the peripheral IC, and in that the buffered operating parameter is transferred into a working register only if a transfer signal is sent from the central IC via the bus connection. This method has the advantage that, for example in the case of rapidly changing receive conditions in a send/receive unit, adjustment of the send or receive gain setting is very flexible, and it is easy to avoid an incorrect setting due to a detected signal fluctuation. The invention also relates to a device for carrying out said method.

Abstract: A system includes a radio frequency transceiver. A baseband processor includes an automatic gain control module. The automatic gain control module has a gain that changes from and subsequently returns to a predetermined value each time the radio frequency transceiver receives a radio frequency signal. The baseband processor is configured to selectively generate an interrupt signal each time a radio frequency signal is received based on a magnitude of the change in the gain of the automatic gain control module and a length of time in which the gain returns to the predetermined value. A control module is configured to identify a radio frequency signal received by the radio frequency transceiver as a radar signal in response to the baseband processor having generated a plurality of interrupt signals at substantially equal time intervals.

Abstract: A wireless receiver utilizes a single analog oscillator to down-convert multi-carrier signals in one or more receiver front-end paths. The received signals are digitized, and the different carrier signals received at each antenna are separated in digital domain by mixing the digitized signal from each antenna with a carrier/antenna separation digital oscillator to down-convert a desired carrier signal and low-pass filtering to remove unwanted carriers. A coarse frequency correction adjusts the analog oscillator, and fine frequency corrections adjust digital oscillators mixing with the separated signals. In one embodiment, the fine frequency correction is applied to the carrier/antenna separation digital oscillators in the separation function. In another embodiment, the fine frequency correction is applied to frequency adjustment digital oscillators mixing with the separated signals. The frequency corrections may be based on reference symbols in the received signals.

Abstract: A wireless receiver with automatic gain control and a method for automatic gain control of a receiving circuit utilized in a wireless receiver are provided. The receiving circuit includes a programmable gain amplifier and a low noise amplifier, and the method includes: comparing a gain code of the programmable gain amplifier with a predetermined code range, wherein the gain code is determined by a frequency signal received through the low noise amplifier; and adjusting a gain of the low noise amplifier when the gain code is out of the predetermined code range.