Abstract: A modulator generates a baseband digital signal from an information-bearing digital signal. The baseband signal has time-varying phase and amplitude defined by a sequence of complex data words, each having an in-phase (I) component and a quadrature (Q) component. A noise-shaping modulator generates a noise-shaped digital signal from the baseband digital signal such that quantization noise in the noise-shaping modulator is attenuated by a spectral null of its noise transfer function. The spectral null is selected by a noise-shaping parameter corresponding to a selected one of a plurality of output frequencies. A signal converter generates an analog signal conveying the information of the information-bearing digital signal on an analog carrier signal having the selected output frequency.

Abstract: A binary bi-phase shift modulator having an input piezoelectric transducer and an output piezoelectric transducer connected in series between a radio frequency input and a radio frequency output. A fixed DC pole voltage having a first polarity is connected to one of the transducers. A DC switched pole voltage is connected to the other transducer which switches between the pole voltage of the first polarity and a pole voltage of the opposite polarity in accordance with a binary data signal. The polarity of the radio frequency input relative to the radio frequency output varies as a function of the polarity of the DC switched pole voltage.

Abstract: A modulator for an electrical signal comprises a data input port and a clock frequency input port. The modulator also comprises a first phase shifter for subjecting input clock frequency signals to a phase shift and adapted to keep the phase of an input clock frequency signal aligned with the phase of a data stream which is input at the data input port. The modulator also comprises a first XOR gate with an output port, to which first XOR gate said input ports of the modulator are connected, by means of which a BPSK signal is created at the output port when a first data stream is connected to the data input port and a first clock frequency signal is connected to the clock frequency input port.

Abstract: A phase shifter includes controlling a phase of an output signal of an orthogonal modulator; and interchanging two kinds of signals inputted to the orthogonal modulator, interchanging each polarity of the two kinds of signals inputted to the orthogonal modulator, or interchanging both of the above. The two kinds of signals inputted to the orthogonal modulator are two pairs of differential signals.

Abstract: A method and system for achieving increased efficiency in a quadrature modulated power amplifier (11) are disclosed. In some embodiments, a supply path (36, 40) and a gain path (38, 42) are provided in each of an I-channel and a Q-channel. The supply path (36, 40) produces a variable voltage and the gain path (38, 42) produces a gain control signal. The variable voltage and gain control signal are used by a variable gain power amplifier (44, 46) to modulate a local oscillator signal to produce a modulated radio signal.

Abstract: A modulating device including: a first convertor configured to generate a converted analog signal by analog conversion on a input digital signal, a modulator configured to generate a modulated signal by quadrature modulation, a phase shifter configured to generate a phase shift signal by phase rotation, a demodulator configured to generate a demodulated signal by quadrature demodulation, a second convertor to generate a converted digital signal by digital conversion, a calculating circuit configured to estimate a the first direct current offset based on the input digital signal and the converted digital signal, the first direct current offset being a noise of digital current component generated between the input digital signal inputted to the first convertor and the output signal inputted to the demodulator, and a correcting circuit configured to correct at least one among from the input digital signal to the output signal based on the first direct current offset.

Abstract: Communication systems are described that use geometrically shaped constellations that have increased capacity compared to conventional constellations operating within a similar SNR band. In several embodiments, the geometrically shaped is optimized based upon a capacity measure such as parallel decoding capacity or joint capacity. In many embodiments, a capacity optimized geometrically shaped constellation can be used to replace a conventional constellation as part of a firmware upgrade to transmitters and receivers within a communication system. In a number of embodiments, the geometrically shaped constellation is optimized for an Additive White Gaussian Noise channel or a fading channel. In numerous embodiments, the communication uses adaptive rate encoding and the location of points within the geometrically shaped constellation changes as the code rate changes.

Abstract: Forward error correction (FEC) m-bit symbol modulation. Any desired FEC, error correction code (ECC), and/or combination thereof generates coded bits for combination with either uncoded bits, separately generated coded bits, and/or combination thereof to generate a number of symbols that undergo mapping to a constellation whose respective constellation points have a mapping characterized by a maximum minimum intra-Euclidean distance between the respective constellation points thereby generating a sequence of discrete-valued modulation symbols. The sequence of discrete-valued modulation symbols may then undergo modulation of any of a number of different operations (e.g., digital to analog conversion [e.g., digital to analog converter (DAC)], scaling, frequency shifting, filtering, etc.) to generate a continuous time signal for transmission via a communication channel. Such a device operative to perform including such functionality, circuitry, capability, etc.

Abstract: Systems and methods are disclosed for feeder link configurations to layered modulation. One feeder link system employs feeder link spot beam to antennas in distinct coverage areas to enable frequency reuse. Another system employs narrow beam width feeder link antenna to illuminate individual satellites also enabling frequency reuse. Yet another system uses layered modulation in the feeder link. Another feeder link system employs a higher order synchronous modulation for the satellite feeder link than is used in the layered modulation downlink signals.

Abstract: A 4-phase filter includes four filter units including resistors and capacitors which inputs input signals, and provides the input signal via a switch buffer to a secondary capacitor provided in parallel to a primary capacitance of each filter unit, thus enabling a shift of an operational frequency band according to whether or not the switch buffer is in an output-high-impedance state.

Abstract: A calibration system may be provided for calibrating wireless communications circuitry in an electronic device during manufacturing. The calibration system may include data acquisition equipment for receiving an amplitude-modulated calibration signal from the electronic device. The calibration system may include calibration computing equipment for extracting pre-distortion coefficients from the amplitude-modulated calibration signal. The calibration computing equipment may be configured to detect a bulk phase drift in the amplitude-modulated calibration signal. The calibration computing equipment may be configured to remove the bulk phase drift from the amplitude-modulated calibration signal. The wireless communications circuitry may include a power amplifier that distorts a signal generated by the wireless communications circuitry. The wireless communications circuitry may include a pre-distortion compensator for countering the distortion.

Abstract: A digital data signal, such as a digital video signal, is intentionally pre-distorted before being sent over a network. In one embodiment, this pre-distortion may be performed in accordance with a pre-distortion pattern or algorithm which is shared with only intended receivers. The pre-distortion pattern may be used to vary the pre-distortion on a periodic basis, as frequently as on a symbol-by-symbol basis. The pre-distortion function may include distorting the phase and/or the amplitude of the digital signal's modulation.

Abstract: In one embodiment, a sequence of a plurality of pairs of in-phase (I) and quadrature (Q) modulated signal samples are applied to a radio frequency digital-to-analog converter (RFDAC) for upconversion. A phase of a local oscillator (LO) signal supplied to the RFDAC is selected according to a quadrant determined by signs of a given pair of I and Q modulated signal samples. The selected phase of the LO is supplied to the RFDAC for use in upconverting the sequence of I and Q modulated signal samples. In another embodiment, a current steering DAC is used for directly upconverting the I and Q modulated signal samples. A clock signal at four times the LO frequency is supplied to a counter and to the current steering DAC. One of the I and Q modulated signal samples and negative I and negative Q modulated signal samples is selected for supply to an input of the current steering DAC based on a count state of the counter.

Abstract: A system and method for a radio controlled clock receiver adapted to extract timing and time information from a phase modulated signal. The official time signal is broadcast from a central location using a modified modulation scheme, which adds phase modulation over the legacy amplitude modulation, such as the legacy WWVB pulse width modulated (PWM)/amplitude shift keying (ASK) modulation, thereby allowing for improved performance. The information modulated onto the phase contains a known synchronization sequence having good autocorrelation properties, error-correcting coding for the time information and notifications of daylight-saving-time (DST) transitions that are provided months in advance. The modulation scheme is based on a form of phase modulation, such as binary-phase-shift-keying (BPSK) or phase reversal keying (PRK).

Abstract: A quadrature out-phasing system comprising: a first baseband signal modifier (6) arranged to receive a first baseband signal component (2) and output a first constant envelope RF carrier (12) and a second constant envelope RF carrier (14); and a second baseband signal modifier (8) arranged to receive a second baseband signal component (4) and output a third constant envelope RF carrier (16) and a fourth constant envelope RF carrier (18). The system may further comprise: a first signal combiner (500) arranged to combine the first constant envelope RF carrier (12) and the second constant envelope RF carrier (14), and arranged to output a first RF PWM signal (94); and a second signal combiner (502) arranged to combine the third constant envelope RF carrier (16) and the fourth constant envelope RF carrier (18), and arranged to output a second RF PWM signal (96).

Abstract: The LINC modulator includes: a separator that generates a plurality of constant envelope signals from a source signal; a plurality of arms through which the plurality of the constant envelope signals are passed, wherein each arm includes a filter that compares frequencies of components of the constant envelope signals with a threshold frequency to generate a first signal including a first frequency part of the source signal, the first frequency part being composed of frequencies lower than a predetermined frequency; a processor that generates a second signal including a second frequency part of the source signal whose frequencies are different from the first frequency part and performs a frequency signal distortion of the second signal to generate a distorted signal; and a quadrature modulator that multiplies the first and distorted signals to reconstruct the constant envelope signals.

Abstract: A method includes obtaining an input signal and demodulating phase contamination in the input signal to generate a baseband signal. The method also includes modulating the input signal based on the baseband signal to generate an output signal, where the output signal has less phase contamination than the input signal. The phase contamination could be demodulated using a phase demodulator or a frequency modulation (FM) detector. A portion of the input signal could be down-converted to a lower frequency, and the phase contamination in the down-converted portion of the input signal could be demodulated. Additional phase contamination in the output signal can be demodulated and used to regulate a level of the baseband signal used during modulation of the input signal. The output signal could have less phase noise or period jitter than the input signal.

Abstract: A method for influencing electromagnetic radiation in a frequency range between 0.1 and 10 terahertz includes providing a planar modulator having a matrix of at least 10×10 individual, active planar elements. Each planar element has a diameter between 5 ?m and 100 ?m. The planar elements are individually controlled using a central control unit such that each planar element assumes a respective one of at least two states in accordance with the control so as to influence the radiation.

Abstract: A method and system is provided for communicating distinct data over a single frequency using on-off keying, a form of amplitude modulation, or phase changes timed to the zero crossing point of the carrier. A data signal is synchronized with the carrier by adding padding bits so that the number of bits is equal to the frequency of the carrier. The carrier is then modified by attenuating the carrier as needed once per cycle. Said carrier is then transmitted. The resulting transmitted carrier carries a number of bits equal to the transmit frequency. At the receive end, the received signal is compared to a sine wave to determine if the incoming signal is at full strength or at reduced strength, allowing for the detection of encoded digital information. In a another embodiment, the phase of the carrier is changed instead of attenuating the carrier, timed to the carrier cycles, once or twice per cycle.

Abstract: An integrated circuit comprises frequency generation circuitry for controlling a frequency source for use in an automotive radar system. The frequency generation circuitry comprises low-path modulation circuitry arranged to generate a first, low-path control signal for providing lower frequency modulation of the frequency source, the low-path modulation circuitry comprising a Phase Locked Loop (PLL) arranged to generate the low-path control signal for controlling the frequency source and a fractional-N divider located within a feedback loop of the PLL, and frequency pattern control module operably coupled to the fractional-N divider and arranged to control the fractional-N divider, by way of at least a first, lower frequency pattern control signal. The frequency generation circuitry further comprises high-path modulation circuitry arranged to generate a second, high-path control signal for providing higher frequency modulation of the frequency source.

Abstract: An apparatus for phase modulation includes a delay locked loop configured to generate from a reference signal a plurality of phase shifted signals, each of the phase shifted signals being locked to the reference signal and having a different phase shift from the other phase shifted signals with respect to the reference signal, and a multiplexer configured to select one of the phase shifted signals.

Abstract: The present invention relates to a digital modulation method and a corresponding modulator. The modulator comprises a transcoder (110) followed by a FIFO register (120) and a 2-PSK modulator (130). The transcoder codes a binary word of fixed size into a code word of variable size using a transcoding table. The transcoding table codes at least one first binary word, leading to a first number of phase transitions at the output of the modulator, into a second word of size greater than that of the first word, leading to, at the output of the modulator, a second number of phase transitions less than the first number of phase transitions.

Abstract: A method for transmitting, by a transmitting terminal, data to a receiving terminal in a wireless communication system includes: generating a first detection field including symbols modulated by using a BPSK data tone; generating a second detection field including symbols modulated such that an even numbered subcarrier and an odd numbered subcarrier have a phase difference of 90 degrees; generating a data packet including the first detection field, the second detection field, and the data; and transmitting the data packet.

Abstract: A method for modifying a characteristic of a representation of a complex-valued signal which comprises at least a representation of a first and a second complex-valued symbol comprising deriving a relative phase angle between the representation of the first and the second complex-valued symbols. The method further comprises combining a representation of a complex-valued enhancement pulse and the representation of the complex-valued signal to obtain a representation of a first and a second corrected complex-valued symbol, wherein the enhancement pulse is chosen such that the relative phase angle between the first and second corrected symbols is smaller than a predetermined threshold.

Abstract: A modulator generates a baseband digital signal from an information-bearing digital signal. The baseband signal has time-varying phase and amplitude defined by a sequence of complex data words, each having an in-phase (I) component and a quadrature (Q) component. A noise-shaping modulator generates a noise-shaped digital signal from the baseband digital signal such that quantization noise in the noise-shaping modulator is attenuated by a spectral null of its noise transfer function. The spectral null is selected by a noise-shaping parameter corresponding to a selected one of a plurality of output frequencies. A signal converter generates an analog signal conveying the information of the information-bearing digital signal on an analog carrier signal having the selected output frequency.

Abstract: A method of transmitting data in a wireless communication system from a transmitter to a receiver, including the steps of modulating data at the transmitter using a first signal constellation pattern to obtain a first data symbol. The first data symbol is transmitted to the receiver using a first diversity branch. Further, the data is modulated at the transmitter using a second signal constellation pattern to obtain a second data symbol. Then, the second data symbol is transmitted to the receiver over a second diversity path. Finally, the received first and second data symbols are diversity combined at the receiver. A transmitter and a receiver are embodied to carry out the method above.

Abstract: Methods, systems and software are provided for high order signal modulation based on improved signal constellation and bit labeling designs for enhanced performance characteristics, including decreased power consumption. According to the improved signal constellation and bit labeling designs for enhanced performance characteristics, designs for 8-ary, 16-ary, 32-ary and 64-ary signal constellations are provided. According to an 8-ary constellation, improved bit labeling and bit coordinates are provided for a 1+7APSK signal constellation. According to a 16-ary constellation, improved bit labeling and bit coordinates are provided for a 6+10APSK signal constellation. According to three 32-ary constellations, improved bit labeling and bit coordinates are provided for a 16+16APSK signal constellation and two 4+12+16APSK signal constellations.

Abstract: A receiver system for early detection of a segment type of an input signal based on BPSK and DBPSK modulated carriers is provided. The receiver system includes a tuner that converts the input signal into an intermediate frequency (IF) signal, a signal conditioning module that converts the IF signal into a baseband signal, a Frequency Domain Synchronization (FDS) block that detects the segment type of the input signal based on a carrier powers, a Transmission and Multiplexing Configuration Control (TMCC) decode block that performs a decoding operation on the received signal, a channel estimation block that estimates a channel and obtains a channel information. The TMCC decode block uses the channel information obtained from channel estimation block to correct a fast-frequency selective fading on the received signal before the decoding operation.

Abstract: Provided is a transmission circuit that operates highly efficiently by avoiding deterioration of the linearity of an output signal and suppressing occurrence of distortion of the output signal, when using the envelope tracking method. In this transmission circuit, offset control section (160) sets voltage that makes the corrected envelope signal level equal to or higher than the delayed envelope signal level, as offset voltage. By this means, the corrected envelope signal level becomes equal to or higher than the delayed envelope signal level, so that it is possible to prevent the power supply voltage from being lower than the optimal power supply voltage, making it possible to prevent the linearity of an output signal from deteriorating in power amplifier (130).

Abstract: A processing device includes a plurality of modulators, the plurality of modulators performing modulation according to a first modulation scheme, a combiner configured to combine outputs from the plurality of modulators, and a signal processor configured to receive a bit stream and convert the bit stream into a plurality of input signals for the plurality of modulators such that the combiner generates a modulated output according to a second modulation scheme. The plurality of modulators may be low order modulators and a modulation schemes of the modulated output may include, for example, rotated quadrature phase shift keying (QPSK), pulse amplitude modulation (PAM), high order quadrature amplitude modulation (QAM), and multi-resolution high order quadrature amplitude modulation (M-QAM).

Abstract: A full spectrum modulator processes a plurality of CATV channels from separate paths. Each path has (i) a first filter for pulse shaping an input channel signal and upsampling a channel frequency thereof, (ii) an interpolator for interpolating the output of the first filter to a common sample rate, and (iii) a decimator for centering the output of the interpolator on a predetermined channel bandwidth. An IDFT processor receives channel signal outputs from the decimators. A polyphase filter bank receives IDFT processed parallel channel signals from the IDFT processor. A commutator converts the processed parallel channel signals from the polyphase filter bank to a single stream of data. A second filter upsamples the single stream of data to a fixed output sampling rate and low pass filters alias signals therefrom. Both standard and harmonically related carrier CATV channel frequency plans are accommodated.

Abstract: A modulation apparatus comprising a first modulating section that outputs a first modulated signal having a fixed amplitude and a set phase; a second modulating section that outputs a second modulated signal having the fixed amplitude and a set phase; an adding section that outputs the output signal as the sum of the first and second modulated signals; a calculating section that calculates two phases to be set respectively in the first and second modulating sections, based on designated amplitude and phase; an allocating section that allocates, for the first and second modulated signals, the two phases calculated by the calculating section such that the first and second modulated signals are each connected more smoothly; and a setting section that sets the phase allocated for the first modulated signal in the first modulating section and sets the phase allocated for the second modulated signal in the second modulating section.

Abstract: Methods, systems, and apparatuses can provide a plurality of RF channels and outputs using digital modulation and combining. In various examples, generation of digital IQ packetized data in combination with digital switching can increase the number of RF modulated channels, optimize broadcast transmission and/or provide transmission resiliency.

Abstract: A wideband phase modulator comprises a multiphase generator, a phase selector, and a phase adjuster. The wideband phase modulator is configured to receive an N-bit digital phase-modulating signal comprising a timed sequence of N-bit phase-modulating words, where N is a positive integer representing the bit resolution of the N-bit digital phase-modulating signal. The multiphase generator generates a plurality of coarse carrier phases, all having the same carrier frequency but each offset in phase relative to the other. The M most significant bits of the N-bit phase-modulating words are used to form M-bit phase select words that control the output phase of the phase selector. The phase adjuster performs a precision rotation operation, whereby a selected coarse carrier phase is adjusted so that the phase of the resulting final precision phase-modulated signal more closely aligns with a desired precision phase.

Abstract: A transmission device includes an RQAM modulating unit that has an S/P that divides a transmitting signal indicating information to be transmitted into a first signal and a second signal, a mapping unit that maps the first signal into a first in-phase component and a second in-phase component and the second signal into a first orthogonal component and a second orthogonal component by a predetermined mapping system, a P/S that generates a first modulated signal including the first in-phase component and the first orthogonal component and a second modulated signal including the second in-phase component and the second orthogonal component, an IFFT that transmits the first modulated signal and the second modulated signal, a DAC, an LPF, a Mixer, a BPF, and a LOCAL OSCILLATOR.

Abstract: A wideband phase modulator comprises a multiphase generator, a phase selector, and a phase adjuster. The wideband phase modulator is configured to receive an N-bit digital phase-modulating signal comprising a timed sequence of N-bit phase-modulating words, where N is a positive integer representing the bit resolution of the N-bit digital phase-modulating signal. The multiphase generator generates a plurality of coarse carrier phases, all having the same carrier frequency but each offset in phase relative to the other. The M most significant bits of the N-bit phase-modulating words are used to form M-bit phase select words that control the output phase of the phase selector. The phase adjuster performs a precision rotation operation, whereby a selected coarse carrier phase is adjusted so that the phase of the resulting final precision phase-modulated signal more closely aligns with a desired precision phase.

Abstract: There are provided a variable inductor with little degradation in quality factor, and an oscillator and a communication system using the variable inductor. An inductance controller comprising a reactance device with a variable device value, such as, for example, a variable capacitor, is connected to a secondary inductor, magnetically coupled to a primary inductor through mutual inductance. The inductance controller is provided with an inductance control terminal for receiving a control signal for controlling capacitance of the variable capacitor. Inductance of the primary inductor is varied by varying the capacitance by the control signal.

Abstract: A circuit includes a phase shifter configured to selectively shift a phase of a baseband phase signal in accordance with a zero crossing signal to output a selectively phase-shifted signal, a phase modulator configured to provide a phase modulated carrier signal in accordance with the selectively phase-shifted signal, and an inverter configured to selectively invert the phase modulated carrier signal in accordance with the zero crossing signal.

Abstract: Polar feedback architecture. A polar modulator, as may be implemented within a transmitter module, of a communication device includes feedback. This feedback involves monitoring of phase information and magnitude/amplitude information of an output signal generated by the polar modulator. The output signal can be a radio frequency (RF) signal such as may be transmitted via a communication channel within a communication system. A baseband processing module processes the monitored phase information and magnitude/amplitude information to perform adjustment of a phase modulator and/or other components within the polar modulator.

Abstract: In order to generate a broadband, frequency-modulated output signal, of which the carrier frequency is adjustable within a wide frequency range, a frequency-modulated signal is generated on an arbitrary, fixed carrier frequency, which is then converted into IQ signals, and the IQ signals generated in this manner are combined with the desired carrier frequency by IQ modulation to form the frequency-modulated output signal. By preference, the generated IQ signals are low-pass filtered before the IQ modulation.

Abstract: A method, system, apparatus and article are described for optimizing transformer power combiners and for dynamically controlling power for outphasing power amplifiers. In some embodiments, for example, an apparatus may comprise one or more outphasing power amplifiers, one or more phase modulator modules coupled to and operative to dynamically control the one or more outphasing power amplifiers, and one or more power combiners coupled to and operative to combine outputs from the one or more outphasing power amplifiers, wherein the one or more power combiners comprise transformer power combiners arranged to combine outphasing signals using a primary inductor and differential signals using a secondary inductor. Other embodiments are described and claimed.

Abstract: A signal modulator includes a discriminator for discriminating a modulation technique through which a carrier signal was modulated to a quasi audio signal and a signal demodulation module for reproducing a continuous data stream from the quasi audio signal through a demodulating technique corresponding to the discriminated modulation technique; the discriminator includes a sampling circuit for extracting groups of samples from the quasi audio signal during each period of the carrier signal, an integrator calculating an integrated value on each group of samples, a comparator comparing the integrated value with a threshold for a neighborhood of zero so as to determine the groups of samples with the integrated value less than the threshold and a determiner measuring the time period between the groups of two modulation period and discriminating 16DPSK when the time period is equal to the modulation period.

Abstract: A method for generating an UWB pulses based on LC oscillator topology. Fast turn on of the oscillator is achieved by creating large asymmetry in a normally symmetrical topology which is used in a typical differential type oscillator. One method for achieving large asymmetry is activating one branch of a differential pair of branches for a short duration before activating both branches in a normal operation. The bandwidth of the pulse is controlled by modifying the duration of the oscillator activation. Fast turn on and turn off is essential for high bandwidth generation. The method is adaptable for generating binary phase shift keying (BPSK) modulation. Selecting the activated branch of a fully symmetrical topology controls the output phase and creates two possibilities which differ exactly by 180 degrees. In a preferred embodiment, all the pulse generator components are on-clip leading to a low cost solution. The circuit can generate high power pulses directly on a load.

Abstract: An vector modulator using a time delay and a phase shifter is disclosed, the vector modulator including a time delay (110) varying a phase of an input signal by time-delaying the input signal; a first coupler (120) converting the signal outputted in changed phase through the time delay to an I channel signal and a Q channel signal each having a 90° phase difference and outputting the I/Q channel signals; a first phase shifter (130) varying the phase of the I channel signal outputted from the first coupler within a predetermined phase range and outputting the phase-variable I channel signal; a second phase shifter (140) varying the Q channel signal outputted from the first coupler within a predetermined phase range and outputting the phase-variable Q channel signal; and a second coupler (150) coupling phase-variable I/Q channel signals and outputting the coupled signals.

Abstract: A redundancy system for a co-channel telecommunication system and related methods. Implementations of the redundancy system may include at least a first modulator and a second modulator having a symbol mapper coupled to a parallel bit signal. The symbol mapper may be configured to route each of a plurality of parallel bits received through the parallel bit signal to a plurality of significant bit signals. In a first implementation, a plurality of significant bit signal multiplexers may be used to switch the plurality of parallel bit signals to allow the first and second modulators to operate in either a redundant or operating mode. In a second implementation, a premapped symbol (PMSI) encoder and a PMSI decoder may be used to transmit the plurality of significant bit signals across an interface bus as a real dual-data rate (DDR) signal and an imaginary DDR signal.

Abstract: A wideband phase modulator comprises a multiphase generator, a phase selector, and a phase adjuster. The wideband phase modulator is configured to receive an N-bit digital phase-modulating signal comprising a timed sequence of N-bit phase-modulating words, where N is a positive integer representing the bit resolution of the N-bit digital phase-modulating signal. The multiphase generator generates a plurality of coarse carrier phases, all having the same carrier frequency but each offset in phase relative to the other. The M most significant bits of the N-bit phase-modulating words are used to form M-bit phase select words that control the output phase of the phase selector. The phase adjuster performs a precision rotation operation, whereby a selected coarse carrier phase is adjusted so that the phase of the resulting final precision phase-modulated signal more closely aligns with a desired precision phase.

Abstract: The LINC modulator includes: a separator that generates a plurality of constant envelope signals from a source signal; a plurality of arms through which the plurality of the constant envelope signals are passed, wherein each arm includes a filter that compares frequencies of components of the constant envelope signals with a threshold frequency to generate a first signal including a first frequency part of the source signal, the first frequency part being composed of frequencies lower than a predetermined frequency; a processor that generates a second signal including a second frequency part of the source signal whose frequencies are different from the first frequency part and performs a frequency signal distortion of the second signal to generate a distorted signal; and a quadrature modulator that multiplies the first and distorted signals to reconstruct the constant envelope signals.

Abstract: A method and device for the simultaneous compensation of several signal errors that occur in an IQ-modulator, using respective inverse correction signals, wherein the optimized signal magnitude of each correction signal is calculated by the determination of the effective signal error and by the subsequent iterative minimization of the effective signal error.

Abstract: In one embodiment, a local oscillator (LO) is configured to generate an LO signal. A transmission line receives the LO signal from the local oscillator and transmits the LO signal. A first set of taps and a second set of taps tap the transmission line to receive the LO signal. A plurality of transceiver blocks are configured to receive and transmit a plurality of phase-shifted radio frequency signals. Each transceiver block is coupled to a first tap and a second tap. Each LO signal received for a transceiver block is received with a different phase. However, the same reference phase may be calculated from a first LO signal received from the first tap and a second LO signal received from a second tap. Each transceiver block receives the reference LO signal having the reference phase determined from the first LO signal and the second LO signal.

Abstract: A constrained-envelope digital-communications transmitter circuit (22) in which a binary data source (32) provides an input signal stream (34), a phase mapper (44) maps the input signal stream (34) into a quadrature phase-point signal stream (50) having a predetermined number of symbols per unit baud interval (64) and defining a phase point (54) in a phase-point constellation (46), a pulse-spreading filter (76) filters the phase-point signal stream (50) into a filtered signal stream (74), a constrained-envelope generator (106) generates a constrained-bandwidth error signal stream (108) from the filtered signal stream (74), a delay element (138) delays the filtered signal stream (74) into a delayed signal stream (140) synchronized with the constrained-bandwidth error signal stream (108), a complex summing circuit (110) sums the delayed signal stream (140) and the constrained-bandwidth error signal stream (108) into a constrained-envelope signal stream (112), and a substantially linear amplifier (146) amplifies