Abstract: A receiver and a transmitter that copes with interference in a super-regenerative communication system, and a method of using the receiver and the transmitter, are provided. A super-regenerative receiver includes a resonance frequency adjusting unit configured to adjust a resonance frequency associated with a filtering band of a transmission signal that is received from a transmitter. The super-regenerative receiver further includes an oscillation signal generating unit configured to generate an oscillation signal, using a positive feedback amplification, based on the resonance frequency and the transmission signal. The super-regenerative receiver further includes an oscillation characteristic detecting unit configured to detect a characteristic of the oscillation signal. The super-regenerative receiver further includes a determining unit configured to determine whether interference is included in the transmission signal based on the characteristic of the oscillation signal and the resonance frequency.

Abstract: A carrier frequency offset (CFO) estimation and synchronization method and apparatus of an orthogonal frequency division multiplexing (OFDM) receiver receiving an OFDM modulated signal. The OFDM receiver's CFO synchronization method includes step (a) performing an initial CFO estimation pull-in step using double correlation, step (b) performing a coarse residue CFO estimate acquisition step using independent combination of the double correlation and auto-correlation, and step (c) performing a small residue CFO tracking step by using the double correlation. Aspects of the invention solves the problems in the related art that a CFO tracking range cannot be reliably used in practice when the CFO tracking range is too narrow and a CFO estimation error increases when the CFO tracking range is too wide.

Abstract: A digital exciter is presented herein for use in RF broadcasting and wherein the exciter employs pilot signal compensation. This includes an input digital circuit for receiving a modulated digital data at an input sample rate for RF broadcasting at a desired RF frequency. The pilot frequency may be displaced from a desired location at the frequency band because of an error in the input sample rate. A digital compensator determines whether the pilot frequency is displaced and provides a digital correction signal in accordance therewith. A digital correction circuit corrects the pilot frequency in accordance with the correction signal.

Abstract: The present invention aims at eliminating the effects of frequency offsets between two transceivers by adjusting frequencies used during transmission. In this invention, methods for correcting the carrier frequency and the sampling frequency during transmission are provided, including both digital and analog implementations of such methods. The receiver determines the relative frequency offset between the transmitter and the receiver, and uses this information to correct this offset when the receiver transmits its data to the original transmitter in the return path, so that the signal received by the original transmitter is in sampling and carrier frequency lock with the original transmitter's local frequency reference.

Abstract: A receiver includes an oscillator for generating a local oscillator signal, a frequency converter for heterodyning a received signal of one frequency band or a plurality of frequency bands into an intermediate frequency (IF) signals with using the local oscillator signal, a filter connected to an output of the frequency converter and having a cut-off frequency changeable, an analog-digital (AD) converter connected to an output of the filter to convert an analog signal of one frequency band or a plurality of frequency bands into a digital signal, a pre-stage detector connected to an output of the AD converter or connected between the filter and the AD converter to detect a signal level, and a controller for controlling the cut-off frequency of the filter based on the signal level detected by the pre-stage detector.

Abstract: A frequency tracking method and apparatus is provided. A receiver receives OFDM symbols and determines associated frequency offset. A frequency error estimator selects a cross correlation window for determining frequency offset based on timing offset. A symbol timing estimator is used to determine the timing offset.

Abstract: Provided is an apparatus for estimating a frequency offset by one training symbol including two symbols having the same structure and value in an OFDM system. The apparatus includes a first likelihood function calculator for modeling non-Gaussian impulsive noise included in the training symbol to a Cauchy probability density function in which a characteristic exponent of a BIS?S probability density function is 1, and calculating a likelihood function of a Cauchy distribution using the Cauchy probability density function, and a first frequency offset estimator for estimating an effective frequency offset value in which the likelihood function of the Cauchy distribution of the first likelihood function calculator becomes highest as a frequency offset estimation value. Thereby, it is possible to improve the performance of frequency offset estimation in non-Gaussian impulsive noise environments.

Abstract: A transmitter and/or receiver for performing frequency domain equalization is provided. A transmitter includes a pilot position determination unit for determining positions for inserting pilots in a frequency domain based on frequency spectrums of data, and a pilot insertion unit for inserting the pilots between the frequency spectrums of the data according to the determined positions for inserting the pilots.

Abstract: A method and system of fine timing synchronization for an OFDM signal. The OFDM signal is coarse timing synchronized, generating a synchronization sequence and a CFR (Channel Frequency Response). The synchronization sequence is removed. A correlation coefficient of the correlation between the CFR applied to a number of carriers and the number of carriers with different window shifts is calculated. The largest window shift corresponding to a downsampling factor is indicated by the lowest correlation coefficient greater than a threshold. The CFR is downsampled by the downsampling factor, and an inverse FFT is performed on the downsampled CFR with a reduced number of calculations reduced by the downsampling factor, transforming the CFR into a CIR. A fine timing synchronization position is determined from the CIR and is utilized by an FFT unit within an OFDM receiver to accurately receive OFDM symbols of the OFDM signal.

Abstract: Disclosed is a wireless signal receiving apparatus, and more particularly, disclosed is a parallel automatic frequency offset estimation apparatus and method for tracking a frequency offset in an early stage by calculating, in parallel, frequency offsets of a received signal. The parallel automatic frequency offset estimation apparatus includes a receiving unit to receive a data frame; and a frequency offset estimation unit to calculate, in parallel, frequency and phase deviations at different bit intervals within a particular section of the received data frame, to add together the frequency and phase deviations to obtain a first sum of the frequency and phase deviations, and to add the first sum to a frequency phase deviation calculated for each bit after the particular section in the received data frame to obtain a second sum of the frequency and phase deviations.

Abstract: Methods and systems for impairment shifting may comprise receiving radio frequency (RF) signals in a receiver, downconverting the signals to baseband frequencies, and synchronizing the receiver to received signals. The frequency of a local oscillator (LO) may be adjusted to shift residual impairments to fall between desired baseband signals where they are least visible. The received RF signals may comprise analog, satellite, or cable, television signals. The LO frequency may be adjusted to configure the DC offset impairments to fall between luminance and chrominance harmonics. The LO frequency may be adjusted to configure I/Q imbalanced impairments from residual in-phase and quadrature mismatch of a picture carrier signal to fall about 300 kHz from a sound carrier signal in the analog television signals. The LO frequency may be adjusted to configure the I/Q imbalanced impairments from residual I/Q mismatch of a sound carrier signal to fall between luminance and chrominance harmonics.

Abstract: A system and method are provided for carrier frequency offset (CFO) and Doppler frequency estimation and correction for Orthogonal Frequency-Division Multiple Access (OFDMA) and Single Carrier-Frequency-Division Multiple Access (SC-FDMA) signals in a wireless communications receiver. The receiver is capable of accepting a plurality of multicarrier signals transmitted simultaneously from a plurality of transmitters, with overlapping carrier frequencies and orthogonal reference signals. For each multicarrier signal, a channel estimate is performed and the channel is equalized. Then, a frequency offset is estimated between the transmit carrier frequency of each multicarrier signal and a receiver local oscillator frequency using either the phase rotation of data constellations as a function of time or the phase rotation of channel estimates as a function of time. The receiver supplies the CFO/Doppler frequency estimates and corrects the equalized symbols prior to demodulation.

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 method an apparatus for performing automatic frequency compensation (or control) is disclosed. A method and apparatus for performing automatic frequency compensation (or control) is disclosed. In one embodiment, a method includes a radio receiver receiving a radio signal and detecting a preamble in the radio signal. The method further includes freezing an automatic frequency compensation (AFC) loop responsive to detecting the preamble. A clock source of the AFC loop may be switched from a first clock signal to a second clock signal. The method further includes subsequently unfreezing the AFC loop.

Abstract: Methods for coherent and non-coherent demodulation are disclosed. Embodiments herein relate to wireless communication systems, and more particularly, to demodulating block orthogonal codes in wireless communication systems. Coherent detection of signals provides improved performance at higher complexity of implementation, but it can be difficult to keep the frequency errors in a wireless communications receiver within the required limits for coherent detection. Embodiments disclosed enable means of using coherent demodulation for block orthogonal codes in the presence of high frequency errors, through the use of techniques of frequency prediction, estimation and correction. Further, it enables a low complexity frequency estimator which provides high estimation range and accuracy.

Abstract: A wireless communication system comprises a wavelet analyzer and a wavelet signal generator. The wavelet analyzer is operable to analyze wireless signals within a frequency and time map of a communications spectrum, whereby the wavelet analyzer is adapted to determine one or more available cells within the frequency and time map. The wavelet signal generator is operable to generate one or more wavelet signals for transmission within the determined one or more available cells of the frequency and time map based on the analyzed wireless signals within the frequency and time map.

Abstract: A filter circuit including first and second real filters of a zero-IF scheme. The first and second real filters receive an I component and a Q component separated from a reception signal, respectively; and a switch section for producing a complex filter by switchably connecting the first and second real filters through interconnection elements. The switch section further receiving a switching signal for connecting the first and second real filters, thereby switching from the zero-IF scheme to a low-IF scheme.

Abstract: An adaptive receiver equalizes incoming data expressed as a series of symbols, the degree of equalization being adjusted by some adaptive control logic. An amplitude detector samples the amplitude of the eye openings of incoming symbols and conveys the resulting measures of eye amplitude to the adaptive control logic. The control logic experiments with different equalization settings while monitoring the resulting eye amplitude to find the equalization setting that provides incoming data eyes of the highest amplitude. A data filter may be included to enable the amplitude detector only in response to particular incoming data patterns.

Abstract: Methods and apparatus for computing the carrier frequency of a transmitter using frequency modulated digital data to compensate for frequency shifting of the transmitter and the receiver local oscillators and for bandwidth adjustment of the receiver's filter. In particular, methods and apparatus are disclosed for binary systems transmitting “1” and “0” data using decoded or undecoded received signals.

Abstract: A frequency tracking method applied to a positioning system is provided. The method includes receiving a baseband signal, the baseband signal includes a line of sight (LOS) signal and a multipath signal; generating a cost function according to equal step frequencies, the baseband signal and a signal average energy; and generating an estimated LOS frequency according to the cost function.

Abstract: A phase synthesis network having self healing capability. The phase synthesis network includes two phase rotators that receive I and Q input LO signals, that receive a digital control signal, and that can adjust a phase and a gain in response to the digital control signal. An output of each of the phase rotators provides a respective output signal to a switch. The switch provides a selected one of the respective output signals for mixing with a predetermined one of the respective output signals. Two mixers mix signals from the phase rotators with an RF signal. Two analog-to-digital converters provide a respective digital signal representative of the output of the mixers. A baseband digital processor generates digital control signals that are provided to the phase rotators. The circuit has an output terminal configured to provide an output signal representative of the RF signal.

Abstract: An optical receiver comprising a frame detector configured to receive a polarized signal comprising a first bit stream and a second bit stream, and further configured to identify a plurality of frames in the first bit stream and the second bit stream using a composite header, and a time-domain equalizer (TDEQ) configured to separate the first bit stream and the second bit stream using a portion of the composite header.

Abstract: An apparatus includes: an offset adjustment unit that supplies an offset correction signal corresponding to a frequency switching to an adder unit that receives an output from a mixer; a timing adjustment unit that adjusts the timing of a frequency switching signal supplied to a local oscillator and the timing of an offset correction amount switching signal supplied to the offset adjustment unit for changing an offset amount in correspondence with the frequency switching in the local oscillator; a noise amount measurement and calculation unit that receives a signal obtained by amplifying and filtering of the signal from the adder unit, to measure a noise amount of the signal and generates a timing determination signal based on the measured noise amount; and a control unit that controls the timing of the frequency switching signal and the offset correction amount switching signal supplied to the timing adjustment unit, based on the timing determination signal from the noise amount measurement and calculation u

Abstract: A method and apparatus for use in connection with wireless communication to adjust the frequency of an oscillator to synchronize with a received signal by correlating a synchronization code channel with training sequences to estimate relative offsets which are employed to estimate an error, which is then filtered. The filtered output preferably provides a voltage controlling a voltage controlled oscillator (VCO). The same technique may be employed to control a numeric controlled oscillator (NCO).

Abstract: A system and method are disclosed to synchronize adaptively a transform window in a multiple sub-carrier communication system based on analysis of a time domain channel impulse response. A set of frequency domain channel estimates, derived from received and one-dimensional Wiener filter interpolated channel estimates, are transformed into a time domain channel impulse response estimate containing multiple, repeated constituent responses. Each order of the constituent responses in the time domain channel impulse response estimate is associated with a two-dimensional Wiener interpolation filter. The set of two-dimensional Wiener interpolation filters generate interpolated channel estimates to compare with received channel estimates to determine a best channel impulse response order of the constituent responses. The transform window is adaptively updated using the best channel impulse response order.

Abstract: Aspects of a method and system for reducing the complexity of multi-frequency hypothesis testing using an iterative approach may include estimating a frequency offset of a received signal via a plurality of iterative frequency offset hypotheses tests. The iterative frequency offset hypotheses may be adjusted for each iteration. A correlation may be done between a primary synchronization signal (PSS), and one or more frequency offset versions of a received signal to control the adjustment of the iterative frequency offset hypotheses. A frequency of the received local oscillator signal may be adjusted based on the estimated frequency offset. One or more frequency offset version of the received signal may be generated via one or more multiplication, and the multiplication may be achieved via a multiplication signal corresponding to one or more frequency offsets. The frequency offset of the received signal may be estimated via the correlation.

Abstract: An apparatus for converting an analog signal into a digital signal includes: two identical analog-to-digital-converters converting the analog signal into first and second digital time domain signals; first and second transformation units transforming the first and second digital time domain signals into first and second digital frequency domain signals; a frequency compensation unit modifying the second frequency signal to reduce a difference between wanted signal components of the second and first frequency values caused by a difference between frequency responses of the analog-to-digital converters; a comparison unit determining for a same frequency bin corresponding first and second energy values associated to corresponding frequency values of the first and second digital frequency domain signal, and determining a minimum energy value thereof; and a selection unit selecting for a same frequency bin of the digital frequency domain signal the digital frequency domain signal associated to the minimum energy v

Abstract: Embodiments of the invention provide for allocating spectrum in a wireless communication system that supports simultaneously at least a first mode of operation and a second mode of operation. Logic is arranged for determining a proportion of spectrum required for the wireless communication unit to operate simultaneously in both the first mode of operation and the second mode of operation. Logic for allocating spectrum allocates a temporary guard band between a first portion of spectrum for the first mode of operation and a second portion of spectrum for the second mode of operation for use while the wireless communication unit operates simultaneously in the first mode of operation and second mode of operation.

Abstract: Computer implemented methods and systems for the prediction of the reception of a desired in-band on-channel digital audio broadcast signal (IBOC DAB) are described. A method includes computing a first ratio of a weaker undesired adjacent broadcast signal to a stronger undesired adjacent broadcast signal; computing a second ratio of the desired IBOC DAB signal to the stronger undesired adjacent roadcast signal. The method also includes computing a minimum allowable reception ratio based on the second ratio and the slope and intercept of a line, wherein the slope and intercept of the line is based on both (i) a plurality of ratios of a weaker adjacent broadcast signal to a stronger adjacent broadcast signal and (ii) a plurality of ratios of a desired IBOC DAB signal to a stronger adjacent broadcast signal. Reception is predicted when the computed minimum allowable reception ratio is less than the first ratio.

Abstract: A mobile station (14) transmits a signal after connection is established, by using the same number of subcarriers as the number of subcarriers equal to or smaller than a predetermined number used for transmitting a connection request signal (TCCH). A base station (12) detects the number of subcarriers used for transmitting the connection request signal (TCCH) (S106), and controls in accordance with the detected number of subcarriers the passband width of a bandpass filter having a passband with a variable width accommodating the predetected number of subcarriers, for separating a signal of the mobile station (14) falling within the passband from a received signal (S108).

Abstract: The present invention relates to an apparatus and method for estimating a frequency offset in a wireless telecommunication system. The present invention does not estimate an initial frequency offset using a preamble which is the initial symbol of a frame upon estimation of the frequency offset in the wireless telecommunication system, but estimates a frequency offset using correlation of a cyclic prefix (CP) existing in each symbol, thereby eliminating a need to reproduce information about separate preamble signals and preamble signals, and easily estimating a frequency offset using only input signals.

Abstract: Heterodyne commutating apparatuses and methods for creating the heterodyne commutating apparatuses are disclosed. The heterodyne commutating mixer includes a plurality of switches for transferring a radio frequency input signal sequentially during a plurality of local oscillator period timeslots to a plurality of output capacitors. The heterodyne commutating mixer also includes a plurality of inductors added across differential in-phase output terminals and quadrature output terminals. Values of inductance and capacitance are set to achieve resonance at an output intermediate frequency.

Abstract: The present invention aims at eliminating the effects of frequency offsets between two transceivers by adjusting frequencies used during transmission. In this invention, methods for correcting the carrier frequency and the sampling frequency during transmission are provided, including both digital and analog implementations of such methods. The receiver determines the relative frequency offset between the transmitter and the receiver, and uses this information to correct this offset when the receiver transmits its data to the original transmitter in the return path, so that the signal received by the original transmitter is in sampling and carrier frequency lock with the original transmitter's local frequency reference.

Abstract: A communications subsystem for a wireless device for correcting errors in a reference frequency signal. The communications subsystem comprises a frequency generator for generating the reference frequency signal and a closed loop reference frequency correction module that generates a reference frequency adjustment signal for correcting the reference frequency signal when the communications subsystem operates in closed loop mode. The subsystem further includes an open loop frequency correction means that that samples values of the reference frequency adjustment signal during the closed loop mode and generates a frequency correction signal for correcting the reference frequency signal when the communications subsystem operates in a mode other than closed loop mode.

Abstract: Channel estimates respectively associated with OFDM pilot symbols are used to estimate additional parameters such as change in channel phase over time, change in channel phase over frequency, and frequency selectivity.

Abstract: A method of selecting an intermediate frequency (fIF) is disclosed (FIG. 7). The method includes measuring a first signal quality (704) on a first channel at a first intermediate frequency. The method further includes measuring a second signal quality (706) on the first channel at a second intermediate frequency. The intermediate frequency with the best signal quality is selected (710).

Abstract: A system and method for signal mismatch compensation in a wireless receiver is disclosed. The method includes receiving an in-phase (I) signal and a quadrature (Q) signal corresponding to the I signal, the Q signal having an ideal phase offset of 90 degrees from the I signal, where there is a phase and gain mismatch between the I signal and Q signal. The method adjusts the phase offset between the I signal and the Q signal to minimize the IQ power, where the IQ power is the average-time power of a digital baseband in-phase (DB-I) signal and a digital baseband quadrature (DB-Q) signal, corresponding to the I signal and Q signal, respectively. The method adjusts the gain of the Q signal to minimize the IQ power, whereby the phase and gain mismatch between the I signal and Q signal is minimized.

Abstract: Embodiments of a receiver for using a first oscillator signal provided by a crystal resonator to support multiple, different functionalities are provided. The receiver comprises a phase-locked loop (PLL) configured to provide a second oscillator signal based on the first oscillator signal provided by the crystal resonator; a first mixer configured to mix a received signal received over a first input path with the second oscillator signal received over a second input path to provide a first frequency-shifted signal; and an automatic frequency controller (AFC) configured to estimate a frequency offset of the second oscillator signal and adjust the PLL to compensate for the frequency offset. The receiver further can include solutions for mitigating potential sources of noise caused by the frequency of the first oscillator signal not being compensated for by the AFC.

Abstract: Embodiments of a receiver for using a first oscillator signal provided by a crystal resonator to support multiple, different functionalities are provided. The receiver comprises a phase-locked loop (PLL) configured to provide a second oscillator signal based on the first oscillator signal provided by the crystal resonator; a first mixer configured to mix a received signal received over a first input path with the second oscillator signal received over a second input path to provide a first frequency-shifted signal; and an automatic frequency controller (AFC) configured to estimate a frequency offset of the second oscillator signal and adjust the PLL to compensate for the frequency offset. The receiver further can include solutions for mitigating potential sources of noise caused by the frequency of the first oscillator signal not being compensated for by the AFC.

Abstract: Provided are a receiver and a receiving method for a scalable bandwidth in a mobile station of an Orthogonal Frequency Division Multiplexing (OFDM) system. The receiving method includes the steps of: (a) filtering a received RF signal; (b) oscillating a frequency according to a center frequency control signal to output a local oscillation frequency; (c) down-converting the filtered RF signal by using the local oscillation frequency; (d) scalable-filtering the down-converted signal while adjusting a bandwidth according to a bandwidth control signal; (e) controlling gain of the scalable-filtered signal; (f) converting the gain-controlled analog signal into a digital signal by using a sampling frequency matching with a corresponding bandwidth according to an ADC control signal; and (g) demodulating the converted digital signal, outputting the center frequency control signal, the bandwidth control signal, and the ADC control signal according to control information received from an upper layer.

Abstract: Devices, methods, and systems for an orthogonal frequency division multiplexing (OFDM) receiver comprising a processor configured to execute a maximum likelihood timing estimator for OFDM symbol timing, a resampling filter for sampling clock frequency offset correcting via a loop filter, where the loop filter may be configured to receive a symbol timing loop error and provide, via a delay accumulator input signals to the resampling filter, and where the resampling filter may be configured to output a resampled signal for demodulating.

Abstract: A method and apparatus for estimating a frequency response of a channel. The method includes adjusting phase components of estimates of the frequency response to provide phase-adjusted estimates; performing a smoothing operation on the phase-adjusted estimates to provide smoothed phase-adjusted estimates; and generating an output of a reverse phase adjustment, wherein the reverse phase adjustment is performed on the smoothed phase-adjusted estimates.

Abstract: A joint synchronizer and decoder that implements two decision aided processes, which are referred to as “decision aided candidate selection” and “decision aided synchronization and decoding.” Decision aided candidate selection may be used to select a carrier frequency offset by selecting among a number of candidates for this parameter based on an indication of decoding success. Decision aided synchronization and decoding may be used for phase tracking based on an indication of decoding success. Although these joint synchronizing and decoding techniques may be implemented together, they may also be implemented independently. The joint synchronizer and decoder may be implemented within a return channel receiver in a DVB-RCS system using turbo coding and quadrature phase shift key (QPSK) data modulation.

Abstract: An exemplary object is to provide a signal processing circuit, a wireless communication device, and a signal processing method for reducing crosstalk of an adjacent interfering signal in a desired signal. A signal processing circuit 3 according to the present invention includes a power acquisition unit 4 that receives multiple radio signals transmitted with different frequency bands and acquires power intensities of the received radio signals; and a frequency selection unit 5 that selects, from among frequency bands used for radio signals having the power intensity lower than a predetermined power intensity, a frequency band having a relatively low power intensity in a frequency band near the frequency bands as each frequency band in which communication is executed.

Abstract: An apparatus and a method for calibrating IQ mismatch to ensure that an in-phase oscillating signal and a quadrature-phase oscillating signal are orthogonal to each other. The apparatus includes a mixer for mixing the in-phase oscillating signal with the quadrature-phase oscillating signal to generate an output signal, a control module for determining a control signal according to a low-frequency component of the output signal, and a phase adjusting module for adjusting the phase of a specific oscillating signal to ensure that the in-phase oscillating signal and the quadrature-phase oscillating signal are orthogonal to each other. The specific oscillating signal may be the in-phase or the quadrature-phase oscillating signal. The apparatus does not require a digital signal-processing unit to perform complex calculations nor requires additional oscillating sources for calibration. Hence, the circuit design is much simplified, and the consumption of system resources is significantly reduced.

Abstract: An acquisition module includes a coherent correlator configured to receive a transmission having a pilot signal and correlate the received transmission with a local copy of the pilot signal to produce a first output, a delayed correlator configured to delay the first output and correlate the first output with the delayed first output to produce a second output, and a detector configured to detect the pilot signal in the transmission based on the second output.

Abstract: Receiver architectures and methods of processing harmonic rich input signals employing harmonic suppression mixers are disclosed herein. The disclosed receivers, mixers, and methods enable a receiver to achieve the advantages of switching mixers while greatly reducing the mixer response to the undesired harmonics. A harmonic mixer can include a plurality of mixers coupled to an input signal. A plurality of phases of a local oscillator signal can be generated from a single local oscillator output. Each of the phases can be used to drive an input of one of the mixers. The mixer outputs can be combined to generate a frequency converted output that has harmonic rejection.

Abstract: Systems and methods are disclosed that include selecting a sampling frequency and a tuning resolution frequency. These systems and methods may further include determining a wordlength of the phase accumulator, a numeric representation of the phase range, and a reduced representable value of a phase accumulator. In addition, these systems and methods may include operating the phase accumulator, where the phase accumulator creates an output phase accumulator signal. These systems and methods may further includes adjusting the angle of the output phase accumulator signal, where the output phase accumulator signal is adjusted based upon the operation of the phase accumulator, where adjusting the angle of the output phase accumulator signal creates an adjusted output phase accumulator signal and operating a CORDIC module, and where the CORDIC module performs operations upon the output phase accumulator signal based upon the parameters of the phase accumulator.

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: 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.