Abstract: The invention relates to a radiofrequency transmission system comprising: means of producing at least one digital signal quantized on N bits; for each of said at least one digital signal, digital processing means including: Sigma-delta filters capable of producing, on the basis of a digital input signal quantized on N bits, a digital output signal quantized on M bits, where M is less than N; downstream from sigma-delta filters, means of repetition over-sampling; and downstream from over-sampling means, convolution means; digital-to-analogue conversion means capable of converting a digital output signal into an analogue signal; and analogue filtering means capable of filtering said analogue signal so as to select a narrow frequency band which includes the second frequency.

Abstract: A set of data symbols is selected from a set of modulation constellation, and a sample-mean of the set of data symbols is determined. Each data symbol is first shifted by the sample-mean to obtain a shifted data symbol, and then the shifted symbol is multiplied by a first constant to obtain a scaled data symbol. A second constant is added to the scaled data symbol to obtain a mapped data symbol. The sample-mean is multiplied by a third constant to obtain a sample-mean mapped symbol. The set of mapped data symbols and the sample-mean mapped symbol are then transmitted as a resource block.

Abstract: A system and method for substantially reducing average transmit power by omitting the transmission of a majority of pulses by using a modified run length coding to reduce signal power. By lowering the average power, an opportunity is presented to either decrease the total power drawn by the transmitter (battery life) or raise the peak power of all symbols (Eb/No), thereby increasing range of a RF transmission system.

Abstract: A transmitting apparatus and method transmits different modulated signals from a plurality of antennas, and employs a configuration that includes a modulation section that obtains a modulated signal by performing signal point mapping of transmit bits using a signal point arrangement that is divided into a plurality of signal point sets on the IQ plane, whereby the minimum distance between signal points within a signal point set is smaller than the minimum signal point distance between signal point sets; and an antenna that transmits a modulated signal obtained by the modulation section. A signal point generating apparatus generates a first and second symbols to be transmitted by first and second antennas, respectively.

Abstract: Systems and methods for reducing the peak-to-average ratio (PAR) at the transmitter can reduce the dynamic range required in various analog components. PAR can be reduced by applying a time-domain compensation signal which reduces the magnitude of peaks in the time-domain signal prior to transmission where the time-domain compensation signals use tones that are reserved for the purpose of reducing the PAR. The reservation of these reserved tones for PAR can be implemented by altering the typical startup procedures in a digital subscriber line (xDSL) system. The use of the reserved tones to reduce the PAR can be implemented using a low complexity algorithm or using an adaptive technique.

Abstract: A communications device may include In-phase (I) power amplifiers configured to generate I amplified signals, Quadrature (Q) power amplifiers configured to generate Q amplified signals, an I controller coupled to the I power amplifiers and configured to selectively enable some of the I power amplifiers, and a Q controller coupled to the Q power amplifiers and configured to selectively enable some of the Q power amplifiers. The communications device may also include a power combiner configured to combine the I amplified signals and the Q amplified signals in a combined amplified signal, and an antenna coupled to the power combiner.

Abstract: A modulator includes a symbol mapper that is configured to map respective bits sets of a bit sequence corresponding to a burst and including data, training, tail, and guard bits into respective symbols to form a symbol sequence of data, training, tail, and guard symbols. A vector precoder is configured to apply a vector precoding transformation to the data and training symbols to form precoded symbols. These precoded symbols are combined with the tail and guard symbols in a symbol processor to form a sequence of transmit symbols. The record precoding conducted by the modulator of a transmitter enables improved link performance without the cost of increased processing complexity of the receiver algorithm.

Abstract: An input digital signal is periodically and alternately subjected to first modulation and second modulation, being thereby converted into a pair of a baseband I signal and a baseband Q signal. The first modulation and the second modulation are different from each other. The pair of the baseband I signal and the baseband Q signal are outputted. The first modulation may be at least 8-signal-point modulation while the second modulation may be phase shift keying.

Abstract: The invention relates to methods for transmitting and receiving a data bit stream in a communication system using 16-QAM constellations. Further, an apparatus for performing the methods is provided. To improve the bit-error rate performance of the communication using the 16-QAM constellations the invention suggests the use 16-QAM constellations with specially selected mapping rules together with a special constellation rearrangement for creating different versions of the 16-QAM constellations. Further, the data stream is transmitted according to a diversity scheme employing different versions of the 16-QAM constellations obtained adhering the mapping rules and rearrangement rules defined by the invention.

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.

Abstract: An apparatus and method are described for compensating for frequency and phase variations of electronic components by processing packet delay values. In one embodiment, a packet delay determination module determines packet delay values based on time values associated with a first and a second electronic component. A packet delay selection module selects a subset of the packet delay values based on the maximum frequency drift of the first electronic component. A statistical parameter determination module evaluates a first and a second parameter based on portions of the subset of packet delay values. A validation module validates the parameters when each portion the subset of packet delay values includes a minimum of at least two packet delay values. An adjustment module compensates for at least one of a frequency variation and a phase variation of the first electronic component based on the parameters if the parameters are both validated.

Abstract: The present invention provides a method for enabling side channel communication between wireless devices. In one embodiment of the invention the guard tones in wireless OFDM signals are used for side channel communication. In another embodiment of the invention, unused bits in OFDM symbols are used as side channels instead of being padded with zeros or random bits.

Abstract: An apparatus and associated methods for performing space-frequency interleaving in a multicarrier wireless communication system is generally described.

Abstract: System(s) and method(s) are provided to transmit simultaneously a first and a second communication channel in a single-carrier waveform format with disparate error rate requirements. First channel and second channel are coded individually to form an alphabet for a first and second constellation. Prior to transmission, bits of information of the first and second channels are modulated with a hierarchical modulation constellation is generated through a combination of a first a second constellation; each constellation is assigned a configurable weight (e.g., a “hierarchic weight”) that is expressed in terms of a configurable energy ratio. The energy ratio determines the resilience of bits associated with the first and second channel. Bit mapping within the first and second constellation provides redundancy to mitigate error rate within each quadrant of the hierarchical constellation.

Abstract: Filtering and modulating a first bit rate signal into a Gaussian filtered Gaussian Minimum Shift Keyed (GMSK) modulated signal and a second bit rate signal into a Quadrature Amplitude Modulated (QAM) signal. A method for nonlinearly and linearly amplifying GMSK and QAM signals. A diversity receiver and demodulator method for receiving and demodulating transmitted modulated signals. Processing, transmit baseband filtering and modulating signals for providing cross-correlated in-phase and quadrature-phase Gaussian filtered Gaussian Minimum Shift Keying (GMSK) and other cross-correlated modulated signals and spread spectrum Quadrature Phase Shift Keying (QPSK) modulated signals. Transmit processing and filtering for providing time division multiplexed (TDM) Gaussian filtered baseband signal and Orthogonal Frequency Division Multiplexed (OFDM) in-phase and quadrature-phase baseband modulated signal to a cellular network and to separate wireless network.

Abstract: This disclosure relates systems and methods for a high bandwidth modulation and transmission of communication signals.

Abstract: A transmission within a wireless cellular network may include a first and second type of information. A subframe includes a plurality of symbols, at least one symbol is designated as a data symbol and at least one symbol is designated as a reference signal symbol that contains a pre-defined reference signal. The first type of information is embedded in the data symbols. If the second type of data is expected, then the second type of information is embedded in at least one reference symbol by quadrature amplitude modulating the pre-defined reference signal. The subframe is then transmitted from one node in the network to a second node. If it is determined that the second node is not expecting the second type of information, then a discontinuous transmission (DTX) response is embedded in the reference symbol instead of the second type of information.

Abstract: A coding unit for determining two different types of modulation to be applied to two carrier signals such that each modulated carrier signal represents a data symbol in accordance with a group of modulation points, each modulation point representing a modulation of the first type and a modulation of the second type that can be applied to one of the carrier signals, the coding unit being arranged to associate the data symbol with a first one of the modulation points by applying a first mapping function to that data symbol and associate the data symbol with a second one of the modulation points by applying a second mapping function to that data symbol, the first and second mapping functions being such that they each map two different data symbols to a respective common modulation point; and determine the modulation of the first and second types to be applied to the first carrier signal to be the modulation of the first and second types represented by the first modulation point and the modulation of the first an

Abstract: The present disclosure relates generally to a system and method for scrambling in a wireless communication system. In one example, the method includes receiving a bit group representing at least a portion of a signal, where a total number of bits in the bit group is defined by a modulation scheme applied to the signal. A bit of the bit group is identified that indicates a sign of an imaginary part of the signal and another bit of the bit group is identified that indicates a sign of a real part of the signal. Only the two bits indicating the signs of the imaginary and real parts of the signal are scrambled using a random sequence prior to wirelessly transmitting the bit group.

Abstract: Method and system for reducing the power consumption in mobile networks, wherein the communication between a mobile terminal and a base station is QAM modulated. The method comprises: making the base station a dynamic real time analysis of the QAM symbols used in the communication between said mobile terminal and the base station, detecting the most frequently used QAM symbols; obtaining the base station a new assignation of the QAM symbols for the downlink communication; sending the base station the new assignation of the QAM symbols to the mobile terminal; using the mobile terminal and the base station said new assignation of the QAM symbols for the demodulation process and modulation process, respectively, in their subsequent communication.

Abstract: An apparatus comprising an artificial noise (AN) controller coupled to a digital subscriber line (DSL) transmitter and configured to adjust an AN level for a signal transmitted by the DSL transmitter, wherein the AN level is adjusted based on an actual signal to noise ratio (SNR) of the signal from the receiver to achieve a desired SNR for the signal. Also disclosed is a method comprising maintaining a data rate in a line at about a desired level by adjusting an AN level in a transmitted signal based on a SNR of a received signal.

Abstract: A new protocol is proposed for transmission of data through lines such as telephone lines. The tones of a signal are grouped, and Trellis encoding is performed only of the members of a group. The computational cost of coding and decoding the data is reduced (compared to treating all the tones of a given direction equivalently), and the invention makes it possible to significantly reduce the computational and memory requirements of the encoder and decoder. Furthermore, Trellis decoding errors are not propagated between the groups.

Abstract: A code encoding apparatus includes a delay circuit and a code generator. The delay circuit generates delayed information based on p-bit input information received in parallel. The delayed information is generated according to a clock. The code generator generates n·p-bit code based on at least one of the input information and the delayed information, where n is a rational number.

Abstract: Methods and systems for vector combining power amplification are disclosed herein. In one embodiment, a plurality of signals are individually amplified, then summed to form a desired time-varying complex envelope signal. Phase and/or frequency characteristics of one or more of the signals are controlled to provide the desired phase, frequency, and/or amplitude characteristics of the desired time-varying complex envelope signal. In another embodiment, a time-varying complex envelope signal is decomposed into a plurality of constant envelope constituent signals. The constituent signals are amplified equally or substantially equally, and then summed to construct an amplified version of the original time-varying envelope signal. Embodiments also perform frequency up-conversion.

Abstract: Embodiments include transceivers and transmit IQ imbalance correction methods. A transmitter lineup, which includes an equalizer and an RF modulator, receives a stream of baseband samples having real and imaginary components, processes the real components along a first channel, and processes the imaginary components along a second channel to produce processed real and imaginary components. The equalizer equalizes at least one of the processed real components and the processed imaginary components to compensate for offset frequency-dependent components of transmitter IQ imbalance. The RF modulator receives and modulates analog versions of the equalized samples, resulting in an analog RF signal. An embodiment also includes a balancer adapted to apply IQ gain and phase correction to the equalized samples to compensate for offset frequency-independent components of the transmitter IQ imbalance.

Abstract: Provided is a transmission circuit which can adjust a difference between signal delay amounts in the amplitude path and the phase path with a low power consumption. An amplitude modulation section 15 amplitude-modulates a phase modulation signal outputted from a phase modulation section 14 with a voltage control signal provided by a regulator 13 to generate a transmission signal for an output of an antenna. Similarly, a feedback signal generation section 16 amplitude-modulates the phase modulation signal with the voltage control signal to generate a feedback signal FB. The signal FB is fed back to a delay adjustment section 12 and used for calculating and adjusting the difference between the signal delay amounts in the amplitude path and the phase path. The feedback signal generation section 16 is attained by a power amplifier having the same configuration as the amplitude modulation section 15 and a smaller circuit scale.

Abstract: The present invention relates to an apparatus and a method for measuring an in phase and quadrature (IQ) imbalance. One embodiment according to the present general inventive concept can provide a method for measuring a Tx IQ imbalance generated in an IQ up-conversion mixer and an Rx IQ imbalance generated in an IQ down-conversion mixer, that includes measuring a first IQ imbalance corresponding to a first combination of the Rx IQ imbalance with the Tx IQ imbalance, measuring a second IQ imbalance corresponding to a second combination of the Rx IQ imbalance with the Tx IQ imbalance and obtaining the Tx IQ imbalance and the Rx IQ imbalance from the first IQ imbalance and the second IQ imbalance.

Abstract: The present invention relates to a modulation and demodulation method of minimizing an error rate and applying it to a differential operation modulo 4. A modulation apparatus includes a Gray coding circuit 101 to which data of (2n+1) bits are inputted (where “n” is an integer more than 1) and which encodes 2 bits of an input signal of (2n+1) bits to a Gray code as a signal for allowing four quadrants to be identified, an encoding circuit 102 that encodes 3 bits of the input signal of (2n+1) bits as a signal indicating any one of eight subgroups provided in each of the four quadrants so that an average Hamming distance between adjacent subgroups within its quadrant becomes a minimum, and a mapping circuit 104 that maps binary data encoded by the Gray coding circuit 101 and the encoding circuit 102 on the four quadrants.

Abstract: The present invention maps coded bits that have been output from a low density parity check coder 11 onto specific bit positions on a 16 QAM constellation diagram in accordance with a column weighting of the coded bits.

Abstract: A polar transmitter includes: a processor arranged to convert signals from a specific coordinate system to a polar coordinate system, wherein the signals in the polar coordinate system comprises a phase component and an amplitude component; a PM path configured to have a constant PM group delay, for processing the phase component; an AM path, of which an AM group delay is capable of being determined, for processing the amplitude component; and an adjustable delay circuit, arranged to adjust delay of the signals in the specific coordinate system according to the constant PM group delay and the calibrated AM group delay.

Abstract: A system and method that demodulates the phase characteristic of a carrier signal are described. The scrambling of the phase characteristic of each carrier signal includes associating a value with each carrier signal and computing a phase shift for each carrier signal based on the value associated with that carrier signal. The value is determined independently of any input bit value carried by that carrier signal. The phase shift computed for each carrier signal is combined with the phase characteristic of that carrier signal so as to substantially scramble the phase characteristic of the carrier signals. Bits of an input signal are modulated onto the carrier signals having the substantially scrambled phase characteristic to produce a transmission signal with a reduced PAR.

Abstract: Methods, systems, transmitters, and receivers implement and use Quadrature Amplitude Modulation QAM2N modulation types and constellations, where N is a real number, e.g., 1.5; 1.33; 2.5; 3.5. The methods, systems, transmitters, and receivers use constellations with the number of points on the circle not equal to a power of two, sending QAM signals of zero power together with other QAM signals, and/or sending sequences of QAM signals of different types.

Abstract: A transmitting apparatus includes a modulation signal generating section that generates a modulation signal by modulating transmission data using one of a plurality of modulation schemes. The plurality of modulation schemes include a first modulation scheme, a second modulation scheme, and a third modulation scheme, where the first modulation scheme has maximum m-ary modulation value, the second modulation scheme has a lower m-ary modulation value than the first modulation scheme, and the third modulation scheme has a lower m-ary modulation value than the second modulation scheme. The transmitting apparatus also includes a pilot signal generating section that generates a pilot signal having one of a plurality of amplitudes, the pilot signal having a lower amplitude than a maximum amplitude of the first modulation scheme.

Abstract: Disclosed are an apparatus, method, and system for transmitting and receiving high-speed data in point-to-point (P2P) fixed wireless communication. In an apparatus for transmitting high-speed data in P2P fixed wireless communication, an amplitude zero autocorrelation waveform (CAZAC) sequence generator generates and outputs a CAZAC sequence. A frame generator generates a frame in which the CAZAC sequence is arranged as part of a preamble before a payload including actual data. A continuous wave (CW) generator generates and outputs a CW signal. A multiplexer receives the CW signal output by the CW generator, and arranges and outputs the CW signal in a position before a signal output by the frame generator.

Abstract: Provided is a transmitter apparatus including: a signal conversion section for, in polar modulation, converting input data into an amplitude-component signal and a phase-component signal, and in quadrature modulation, converting input data into an in-phase component signal and a quadrature component signal; a carrier wave generation section for outputting a carrier wave; a mixer section for, in quadrature modulation, generating a quadrature modulation signal; a regulator for, in polar modulation, outputting a supply voltage control signal; and a power amplifier for, in polar modulation, amplifying the supply voltage control signal and superimposing the resultant signal onto the carrier wave, thereby generating a transmission signal, wherein in polar modulation, the carrier wave generation section outputs the carrier wave modulated with respect to phase component, and in quadrature modulation, the carrier wave generation section outputs the carrier wave that is yet to be modulated.

Abstract: The invention relates to signal transmission. The use of the invention for transmitting and receiving quadrature amplitude modulation signals on unlicensed frequency bands makes it possible to lower a demodulation threshold owing to a low synchronization threshold. The inventive method consists in extending a burst of M m-level quadrature amplitude modulation signals with the aid of two pseudo-random sequences, one of which is periodically inverted in some bursts, thereby making it possible to extract, on a receiving side, the quadrature amplitude modulation signal components corresponding to a meander signal of the pseudo-random sequence inversion (the frequency of which is known). The inventive method is carried out by means of a corresponding system in a hardware and software mode. Moreover, said method can be used for synchronizing the reception of quadrature amplitude modulation signals.

Abstract: A beamforming RF vector modulator is provided. The beamforming RF vector modulator includes a first amplification part for amplifying an input single RF signal and outputting differential RF signals of different phases; an RF signal converter for receiving the differential RF signals and outputting four signals I+, I?, Q+, and Q? of different phases, the RF signal converter comprising a polyphase filter which is virtually opened by resonance of an output terminal comprising a transmission line load; a Variable Gain Amplifier (VGA) part comprising a I VGA which varies an amplitude and a polarity of the signals I+ and I?, and a Q VGA which varies the amplitude and the polarity of the signals Q+ and Q?according to a control signal; and an RF signal synthesizer for synthesizing an output current of the I VGA and an output current of the Q VGA.

Abstract: The system and method of the present invention provide a single mixer (200-400) with significantly reduced noise performance at a low cost by adding a current control circuit (109) that reduces the current in at least the switching stage (103, 303, 403) during polarity changes of the local oscillator (LO) signal (104). Alternative embodiments (300-400) are provided for a single mixer having significantly reduced noise wherein the low-noise characteristic is enhanced by a further modification to the switching stage (303-403).

Abstract: A device for processing a signal carrying information to be transmitted using a radiofrequency signal, for transformation of the signal into two signals of identical amplitude phase-shifted respectively relative to the information-carrying signal according to two variable and opposing phase shifts. The device includes a mechanism transforming the information-carrying signal. The device transforms the information-carrying signal into two signals of constant amplitude and of variable phase shifts according to values of the information-carrying signal, for as long as the amplitude of the information-carrying signal is greater than a predetermined value, and transforms the information-carrying signal into two signals of variable amplitude according to the values of the information-carrying signal, when the amplitude of the information-carrying signal is less than the predetermined value.

Abstract: A method and apparatus for providing an asymmetrical backwards compatible communications signal that is capable of being decoded by QPSK and OQPSK receivers as well as PSK and QAM receivers is provided. The invention comprises a timing error accumulator coupled to a first bit stream. The first bit stream includes content that is common to the QPSK/OQPSK receiver and to the PSK/QAM receiver. A phase error accumulator is coupled to a second bit stream and adjusts the phase of symbols in the second bit stream. A phase and timing error compensator is coupled to the phase error accumulator and the timing error accumulator and adjusts the first and second bit streams received from the phase error accumulator and the timing error accumulator in order to reduce timing and phase errors. A higher order modulator coupled to the phase- and timing error compensator is also provided. The higher order modulator processes the first and second bit streams to provide the asymmetrical backwards compatible signal.

Abstract: A transmitter circuit includes a first synthesizer section, and a second synthesizer section which consumes less current than the first synthesizer section. The transmitter circuit performs switching such that the first synthesizer section is operated and the second synthesizer section is powered off in polar modulation, and the second synthesizer section is operated and the first synthesizer section is powered off in quadrature modulation, thereby reducing consumed power. While the first synthesizer section is operating, calibration for an oscillation frequency is performed, and when the operation is stopped, a calibration value is stored. When an operation of the first synthesizer section is restarted, the stored calibration value is corrected by using temperature change, thereby enhancing calibration accuracy and preventing degradation in quality of a transmission signal.

Abstract: A media access control (MAC) layer controller can manage base layer data and enhancement layer data in a layered modulation system. The MAC layer controller can process both base layer data and enhancement layer data and map the encoded symbols to a layered modulation constellation when both are present. If data for one of the layers terminates, then the MAC layer controller can generate and supply predetermined stuffing data to the layer lacking additional data. The MAC layer controller can send a control signal to the physical layer hardware to cause the hardware to map the layered signals having the stuffing data to a modified signal constellation. The MAC controller can also generate an overhead message that indicates the occurrence of the stuffing data. The receiver can receive the overhead message and can use the information to configure the receiver for the layered modulation constellation or the modified signal constellation.

Abstract: Test signal generator (3) generates test signals represented, by four points, which comprise two sets of two points positioned in point symmetry with respect to the origin of an I/Q orthogonal coordinate system. Envelope detector (8) detects the amplitude of an envelope of the output signal from an orthogonal modulator when the test signals represented by four points are generated, and outputs a signal proportional to the square of the amplitude. Comparing unit (9) calculates an average value of output signals from envelope detector ( ) when the test signals represented by the two points of each set are generated. Controller (10) adjusts the amplitudes and/or phases of the test signals so that the average values produced when the test signals represented by the two sets of the two points are generated are equal to each other, and calculates an I/Q mismatch quantity based on the adjusted results.

Abstract: An apparatus for data processing in a multi-channel communication system is provided. The apparatus includes an encoder configured to encode a number of bits for transmission via channels in the multi-channel communication system into coded bits and split the coded bits into a number of first sets of bits at a first ratio, a number of first rate units coupled to the encoder, each of the first rate units being configured to adjust one set of the first sets of bits in size at at least one rate, and a controller configured to assign the first ratio to the encoder and the at least one rate to each of the first rate units based on conditions of the channels.

Abstract: Switched-mode amplifiers and devices having such amplifiers include quadrature pulse-width modulation that is based on cartesian (as opposed to polar) coordinates. Two sets of pulses that represent respective in-phase and quadrature components of a conventional cartesian-coordinates input signal can be combined such that the combined set of pulses can be provided to a switched-mode amplifier without nonlinear cartesian-to-polar transformation and its associated wider internal bandwidth and other problems.

Abstract: A system, method and node for modulation and coding scheme adjustment for a Long Term Evolution (LTE) shared Data Channel. The method determines an actual number of orthogonal frequency division multiplexing (OFDM) symbols, NOS utilized for the shared Data Channel. A modulation order for transmission of data on the shared Data Channel is increased when the actual number of OFDM symbols NOS is less than 11 and decreased when NOS is more than 11. A modulation and coding scheme field (IMCS) of a downlink control information of the shared Data Channel may also be determined. If 0?IMCS+11?NOS?28, the modulation order is modified by utilizing a factor of (IMCS+11?NOS) in a standardized modulation scheme. If it is determined that IMCS+11?NOS<0, the modulation order is set to Quadrature Phase Shift Keying (QPSK). If it is determined that IMCS+11?NOS>28, the modulation order is set to 64 Quadtrative Amplitude Modulation (64QAM).

Abstract: A transmission circuit (100) according to the present invention includes an RF-IC (110), an EM-IC (120), and a power amplifier (130). The EM-IC (120) includes a DC-DC converter (123), a transistor (124), a low-dropout regulator (121), and a regulator output selector switch (122). After an elapse of a predetermined time from a time when an operation mode of the transmission circuit has switched from a polar modulation mode to a quadrature modulation mode to a time when a power supply voltage for the quadrature modulation mode output from the DC-DC converter (123) stabilizes at a desired value, the regulator output selector switch (122) switches a connection destination of a gate of the transistor (124) to a fixed potential, and outputs as a control voltage the power supply voltage for the quadrature modulation mode output from the DC-DC converter (123).

Abstract: Systems and methods for encoding user information and decoding signal vectors using fractional encoding/decoding and set partitioning. A fractional encoder can select a coset for transmitting or storing user information based on one or more deterministic bits and on encoded user information. The deterministic bits limit the encoder to using only a subset of the available signal vectors in a modulation scheme. A fractional decoder can receive a signal vector, and can find at least two nearest neighbors in each dimension. The fractional decoder can form a set of potential signal vectors using only the at least two nearest neighbors. The decoder may determine which of these potential signal vectors are valid within the fractional signaling scheme, and can decode the received signal vector based on the valid potential signal vectors.

Abstract: There is an apparatus and technique for generating a sequence of modulated waveforms of finite duration in which the difference in start time of each waveform is shorter than the waveform's overall duration and each waveform in the sequence has independent data modulation imparted upon it. The apparatus consists of a bank of memory cells arranged in an N×M configuration with associated control circuitry, along with an arrangement scheme for the data in the N×M memory cells such that the waveforms will be correctly reproduced when the memory cells are addressed by the control circuitry in the prescribed order.

Abstract: A method for transmitting high rate data within a multiple input multiple output (MIMO) wireless local area network (WLAN) begins by determining a data transmission rate. The method continues by, when the data transmission rate is between a first data rate and a second data rate, enabling two transmission paths. The method continues by, for each of the two transmission paths, determining at least one of: level of constellation, number of data subcarriers, rate code, and cyclic prefix duration.