Class / Patent application number | Description | Number of patent applications / Date published |
375268000 | Amplitude modulation | 44 |
20080267313 | Dual Demodulation Mode AM Radio - Apparatuses and methods for receiving an amplitude modulated signal in one of two modes depending on the quality of the received signal. In a first mode, the amplitude modulated signal is converted directly to a baseband signal. In a second mode, the amplitude modulated signal is converted to an intermediate frequency signal. The present invention advantageously combines direct conversion and image-rejection heterodyne receiver topologies with a relatively large degree of component reuse and relatively few additional components. | 10-30-2008 |
20090074101 | Detection Performance in Communication Systems - A method and system to generate decoded information from received symbols in communication receivers. A first embodiment is a method to detect digitally modulated symbols and generate decoded information. The method includes receiving digitally modulated symbols, demapping the digitally modulated symbols to generate soft decisions representing digitally modulated symbols, multiplying the soft decisions by an adaptive factor to generate scaled soft decisions; and decoding the scaled soft decisions to generate decoded information. A second embodiment is a system having modules to detect digitally modulated symbols and generate decoded information. These embodiments can be applied in several wired and wireless communication applications including, but not limited to, WiMAX applications. | 03-19-2009 |
20090074102 | Method and apparatus for wired signal transmission - A method and apparatus for high quality signal transmission, which utilizes normal-mode current flow and produces an audio output signal with suppression of normal-mode voltage amplitude, comprising transmitting an audio input signal source though (1) a buffer amplifier; (2) a modulated current source; (3) a pair of wires; (4) a current transformer; and (5) a receiver amplifier for said current transformer. | 03-19-2009 |
20090080562 | Wireless SATA/SAS Data Transfer System - A wireless data transfer system. The system includes a first hard disk, a first hard disk interface, and a first transmitter. The first hard disk interface is configured to retrieve first read data from the first hard disk and to create a first bit serial signal from the retrieved first read data. The first bit serial signal conforms to a protocol selected from the group consisting of serial advanced technology attachment (SATA) protocol and serial attached small computer system interface (SAS) protocol. The first transmitter is configured to operate at selected carrier frequency greater than 50 GHz, comprising, to operate at effective isotropic radiated power level less than or equal to 40 dBm, to receive the first bit serial signal from the first hard disk interface, to modulate the first bit serial signal using amplitude shift keying modulation to substantially create directly a first signal, and to transmit the first signal. | 03-26-2009 |
20090252252 | HIGHLY LINEAR EMBEDDED FILTERING PASSIVE MIXER - A communication channel has a highly linear switched current mixer that incorporates passive filtering (e.g., low pass, notch) for improved transmitting (Tx) and receiving (Rx) with adding external filtering components. A high IIP | 10-08-2009 |
20100034313 | SYSTEM AND METHOD FOR ACCURATE DOWNLINK POWER CONTROL OF COMPOSITE QPSK MODULATED SIGNALS - A method for controlling code power levels of individual codes of a composite quadrature phase shift keyed (QPSK) signal. The method may involve obtaining a sample of the composite QPSK signal; separating the individual codes from the composite QPSK signal; analyzing the individual codes against corresponding commanded code power settings for the individual codes; and determining a code power correction signal needed for each of the individual codes needed to adjust a code power for each of the individual codes to match their corresponding commanded code power settings. | 02-11-2010 |
20100067606 | METHOD AND APPARATUS FOR TRANSMITTING/RECEIVING MBMS BASED ON HM - The present invention relates to a communication field and particularly to a method and apparatus for transmitting/receiving multimedia broadcast/multicast data based on hierarchical modulation in order to solve the problem of low efficiency of conventional methods. The method includes the steps of: receiving a check report returned from a receiver, determining whether the check report indicates there are both basic layer and enhanced layer data errors and if yes, exchanging the last two bits of the enhanced layer and the first two bits of the basic layer and modulating the data with a second constellation map and then transmitting the data; otherwise determining whether the check report indicates there is only the basic layer error and if yes, modulating the data with the second constellation map in the order from the basic layer to the enhanced layer and then transmitting the data; if there is only enhanced layer error, exchanging the last two bits of the enhanced layer and the first two bits of the basic layer and modulating the data with the first constellation map and then transmitting the data. The beneficial effects of the present invention are that the retransmission efficiency can be improved and the ratio of receiving the data correctly by the users at the cell center and at the cell border during the first retransmission is improved. | 03-18-2010 |
20100272208 | IMBALANCE COMPENSATION FOR DIRECT CONVERSION COMMUNICATION SYSTEMS - Most modern integrated circuit transceivers, especially wireless LAN, utilize a direct conversion radio architecture, which is highly advantageous from the perspectives of cost and flexibility, there exist several performance impairments, including gain and phase imbalances between the in-phase (I) and quadrature (Q) of a transmitter or receiver. Disclosed herein is a signal processing methodology and system for compensation of I/Q imbalance for a direct conversion packet-switched OFDM communications system. The imbalance, which accounts for transmitter I/Q imbalance, RX I/Q imbalance, phase/frequency error, and dispersive multipath fading. Both frequency dependent I/Q imbalance and frequency independent cases are considered, covering both wideband and narrowband modulation. The proposed estimation algorithms operate within the fully compliant framework of existing multi-user OFDM radio standards (WLAN, LTE, WimAX). These algorithms accurately estimate and correct transceiver I/Q imbalance on a packet-by-packet basis, all within the receiver's digital baseband. | 10-28-2010 |
20110044396 | COMMUNICATION SYSTEM, COMMUNICATION DEVICE, WIRED COMMUNICATION DEVICE, AND COMMUNICATION METHOD - A communication system includes a wired communication device and a communication device that can communicate with a wireless communication device and the wired communication device. The communication device includes a clock output unit and a modulator. The wired communication device includes a clock extracting unit, a signal extracting unit, and a processing unit. The communication device and the wired communication device are connected to each other by a first connecting line through which a modulated signal is sent from the communication device to the wired communication device, and a second connecting line, which is different from the first connecting line, through which a signal is sent from the wired communication device to the communication device. | 02-24-2011 |
20110051836 | Methods and Apparatus for Reducing the Average-to-Minimum Magnitude Ratio of Communications Signals in Communications Transmitters - A communications transmitter configured to reduce the average-to-minimum magnitude ratio (AMR) of a communications signal includes a symbol mapper, a pulse-shaping filter, an AMR reduction circuit, and a modulator. The symbol mapper operates to generate a sequence of symbols from a binary-source data stream containing a message to be transmitted, and the pulse-shaping filter generates a baseband signal based on the sequence of symbols. The AMR reduction circuit is configured to compare magnitudes of samples of the baseband signal to a time-varying low-magnitude threshold, and modify the baseband signal to produce a modified baseband signal having a reduced AMR if a sample of the baseband signal is determined to have a magnitude less than the time-varying low-magnitude threshold. Finally, the modulator operates to modulate a carrier signal based on the modulation information contained in the modified baseband signal. | 03-03-2011 |
20110142155 | QUADRATURE SIGNAL DECODING USING A DRIVER - A system and method for decoding quadrature signals includes a quadrature signal generator, a quadrature signal decoder, a key matrix and a driver. The quadrature signal generator generates quadrature signals on rotation. The quadrature signal decoder is configured to convert the quadrature signals into non-overlapping signals. The key matrix is configured to receive the non-overlapping signals. The driver is configured to scan the key matrix to decode the non-overlapping signals to generate an event update corresponding to a direction of rotation of the quadrature signal generator. | 06-16-2011 |
20110182379 | NETWORK CODING METHOD AND SYSTEM THROUGH CONSIDERATION OF CHANNEL STATE DIFFERENCE OF RECEIVERS - Disclosed is a network coding method and system for receivers having a different channel state that may demodulate and extract a single coded packet using a different demodulation scheme according to a channel state of each receiver. The disclosed network coding method may use a different demodulation scheme to be suitable for a channel state of each receiver by applying a packet encoding scheme combined with a modulation scheme. When two receivers receive a network coded packet, a receiver having a poor channel state may receive a relatively small amount of information from the single packet compared to the other receiver having a relatively excellent channel state, but may enhance the reliability of packet reception. The other receiver having the relatively excellent channel state may decrease the reliability of packet reception, but may receive a relatively large amount of information. | 07-28-2011 |
20110243267 | MAGNETIC FIELD COMMUNICATION METHOD FOR MANAGING NODE WITH LOW POWER CONSUMPTION - A magnetic field communication method is provided for managing node with low power consumption which enhances performance and efficiency of a magnetic field area network in the low frequency region. The magnetic field communication method for managing node with low power consumption of the present invention is accomplished in a low-frequency wireless network that is comprised of a MFAN-C and at least one MFAN-N wherein a physical layer is comprised of a preamble, a header, and a payload, and the preamble is comprised of a wake-up sequence and a synchronization sequence. The wake-up sequence is only added to the preamble of the frame that is transmitted from the MFAN-C when the MFAN-N is being activated from the hibernation mode. The wake-up sequence is modulated using ASK modulation, and the synchronization sequence is modulated using BPSK modulation. | 10-06-2011 |
20110261896 | APPARATUS AND METHOD FOR CREST FACTOR REDUCTION ARCHITECTURE - A device and a method for crest factor reduction reduces peak-to-average ratio (PAR) to increase power amplifier efficiency. A first hard clipping block performs hard clipping on an input signal when the amplitude of the input signal is greater than a first threshold. A shaping filter reshapes the spectrum of the hard clipped signal. An interpolator increases the sampling rate of the reshaped signal. A second hard clipping block performs hard clipping on the interpolated signal when the amplitude of the interpolated signal is greater than a second threshold. | 10-27-2011 |
20110293031 | METHOD AND APPARATUS FOR BIT AND POWER ALLOCATION, AND COMMUNICATION SYSTEM - The present invention discloses a method and apparatus for bit and power allocation and a communication system. The method for bit and power allocation comprises: determining a set of candidate modulation modes for sub-channels; constructing an SNR lookup table according to a predetermined target BER, the SNR lookup table containing a relationship of an SNR and the number of bits corresponding to a modulation mode in the set of candidate modulation modes at the target BER; obtaining normalized SNRs on the sub-channels; initializing the numbers of bits for the sub-channels; initializing powers for the sub-channels according to the numbers of bits for the sub-channels, the normalized SNRs on the sub-channels and the SNR lookup table; and adjusting the numbers of bits and the powers for the sub-channels in accordance with a principle of maximizing power utilization rate, to obtain the result of the bit and power allocation for the sub-channels. | 12-01-2011 |
20110305292 | NONLINEAR FILTER AND TRANSMISSION CIRCUIT - A nonlinear filter includes: a determination unit that determines, based on I and Q signals inputted into the determination unit, whether or not to perform pulse insertion; a rotation detector that detects a rotation direction of the I and Q signals on an IQ plane with respect to the origin of the IQ plane; a pulse generator that generates, when the determination unit determines to perform the pulse insertion, a pulse of which at least one of the direction and the magnitude is determined in accordance with at least the detected rotation direction; and an adder that inserts the pulse into the I and Q signals and outputs resultant I and Q signals. | 12-15-2011 |
20120045009 | TRANSMISSION DEVICE FOR GENERATING AN ANALOG MODULATED PULSE TRAIN AND FOR TRANSMITTING THE SAME AND A RECEIVING DEVICE FOR RECEIVING A RESPECTIVE SIGNAL - The present invention relates to a transmitting device and to a receiving device. In particular, it relates to a transmitting device for producing an analogue modulated pulse train and for emitting the same, comprising a pulse generator ( | 02-23-2012 |
20120093252 | Symbol Synchronization for Communication - A communication system and method is disclosed that performs symbol boundary synchronization by generating a symbol alignment estimate from a partial signal correlation; and then refining the symbol alignment estimate via a carrier phase calculation. To generate the symbol alignment estimate, two methods are disclosed. After an estimate is determined, an embodiment provides for refining the symbol alignment estimate via a carrier phase calculation by determining a carrier phase of two adjacent carriers, determining a phase error as directly proportional to an offset from the start of a symbol, determining a phase difference contribution due to a communication channel and device hardware, and counter-rotating the determined carrier phase by an angle of a constellation point at a transmitter. | 04-19-2012 |
20120147983 | METHODS AND APPARATUSES FOR SIGNALING WITH GEOMETRIC CONSTELLATIONS IN A RALEIGH FADING CHANNEL - Communication systems are described that use signal constellations, which have unequally spaced (i.e. ‘geometrically’ shaped) points. In many embodiments, the communication systems use specific geometric constellations that are capacity optimized at a specific SNR, over the Raleigh fading channel. In addition, ranges within which the constellation points of a capacity optimized constellation can be perturbed and are still likely to achieve a given percentage of the optimal capacity increase compared to a constellation that maximizes d | 06-14-2012 |
20120155563 | Communications System - A communication system comprises a transmitter unit ( | 06-21-2012 |
20120275537 | SYSTEM AND METHOD FOR SENDING AND RECEIVING A DIGITAL SIGNAL OVER A RADIO PATHWAY - A constant-amplitude and continuous-phase modulation method for modulating digital data and for demodulating said modulated signal, said data taking the form of symbols a(n) that can take a number M of states at least equal to 2, the method including, in transmission, use of a voltage-controlled oscillator (VCO) for which the control is the sum of pulses he(a(n), t−n T), the form and the amplitude of which depends on the value of a(n); and, in reception, use of a single impulse response filter C0(t) regardless of the value of M in transmission, said functions he and C0 having a number of parameters that are optimized in the design of the system in order to obtain at the output of the filter C0 a constellation that is as close as possible to the theoretical constellation. | 11-01-2012 |
20130064319 | METHOD AND A DEVICE FOR CONTROLLING THE LEVEL OF A PULSED HIGH-FREQUENCY SIGNAL - A method and a device for controlling the level of a pulsed high-frequency signal amplify or respectively attenuate an un-pulsed high-frequency signal with an amplification or attenuation element adjustable with regard to its amplification or attenuation factor. A pulsed high-frequency signal is generated by a pulse modulator controlled by a pulse signal from the un-pulsed high-frequency signal. At the output of the pulse modulator, a signal level of the pulsed high-frequency signal is measured by a high-frequency detector. The amplification or attenuation factor of the amplification or attenuation element is adjusted with a level controller controlled by the measured signal level. To control the level controller, the measured signal level of the pulsed high-frequency signal is linked to the measured signal level of the pulse signal. | 03-14-2013 |
20130156126 | RAIL-TO-RAIL COMPARATOR, PULSE AMPLITUDE MODULATION RECEIVER, AND COMMUNICATION SYSTEM USING THE SAME - A rail-to-rail comparator including a first comparison unit connected to a first terminal and configured to compare differential input signals to differential reference voltages; a second comparison unit connected to a second terminal and configured to compare the differential input signals to the differential reference voltages; and an output unit configured to be driven in response to a clock signal and to generate a complementary output signal according to comparison results of the first and second comparison units. | 06-20-2013 |
20130315340 | MULTI-DOMAIN NETWORK CODING - A communications network ( | 11-28-2013 |
20140003548 | NFC Device with PLL Controlled Active Load Modulation | 01-02-2014 |
20140140431 | TRANSMITTER CIRCUIT, RECEIVER CIRCUIT, AND TRANSMITTING/RECEIVING SYSTEM - A transmitting/receiving system may include a transmission line, a transmitter circuit configured to transmit a clock to the transmission line and to adjust an amplitude of the clock in accordance with a logic level of data, and a receiver circuit configured to receive the clock transferred to the transmission line and to recover the data through detection of the amplitude of the clock. | 05-22-2014 |
20150023445 | Systems and Methods Utilizing Adaptive Envelope Tracking - A communication system utilizing adaptive envelope tracking includes a transmit path, a feedback receiver, a parameter component and an envelope tracking component. The transmit path is configured to generate a transmit signal. The feedback receiver is configured to generate a feedback signal from the transmit signal. The parameter component is configured to generate linearity parameters from the feedback signal and the baseband signal. The envelope tracking component is configured to generate a supply control signal having time delay adjustments. | 01-22-2015 |
20150023446 | SIGNAL TRANSMISSION DEVICE AND SIGNAL TRANSMISSION METHOD - A signal transmission device includes a signal sender that sends first and second transmission signals of mutually opposite phases, a first transmission path over which the first transmission signal is transmitted, a second transmission path over which the second transmission signal is transmitted, and a signal receiver that converts the first transmission signal received from the first transmission path and the second transmission signal received from the second transmission path into an output signal of a single phase. The signal transmission device differentiates each amplitude of the first and second transmission signals sent from the signal sender, and the signal receiver, based on an amplitude ratio of the first and second transmission signals, converts the received first and second transmission signals. | 01-22-2015 |
375269000 | With phase or frequency shift keying | 15 |
20080205541 | METHOD AND SYSTEM FOR POLAR MODULATION USING A DIRECT DIGITAL FREQUENCY SYNTHESIZER - Methods and systems for polar modulation using a digital direct frequency synthesizer (DDFS) are disclosed and may comprise generating a phase modulated signal in a DDFS, amplitude modulating the generated phase modulated signal in a non-linear device and transmitting the signal via a wireless medium. A processor may control the generation of the phase and amplitude modulated signals. The non-linear device may comprise a non-linear power amplifier or a mixer. The method may also comprise generating a first phase modulated signal in a first DDFS and generating a second phase modulated signal in a second DDFS, or in a single DDFS with two integrated digital-to-analog converters, and upconverting and combining the first and second phase modulated signals and amplitude modulating the combined upconverted signals in a non-linear device. A processor may be enabled to control the generation of the first and second phase modulated signals. | 08-28-2008 |
20080212707 | METHOD AND SYSTEM FOR A DIGITAL POLAR TRANSMITTER - Aspects of a system for a digital polar transmitter may include a digital to analog converter circuit (DAC), for which an analog voltage and/or current step size generated in response to a sequence of received binary numbers may be dynamically programmable based on an input control signal. The input control signal may be based on an amplitude modulation (AM) signal. The DAC may receive the sequence of binary numbers, generated based on a phase modulation (PM) signal, from an accumulator circuit. The dynamically programmable-step-size DAC may generate an analog signal, which is amplified by a power amplifier circuit (PA) and transmitted via an antenna. The dynamically programmable-step-size DAC may enable utilization of a linear PA circuit. | 09-04-2008 |
20080247484 | METHOD FOR DATA COMMUNICATION VIA A VOICE CHANNEL OF A WIRELESS COMMUNICATION NETWORK USING CONTINUOUS SIGNAL MODULATION - A system and method for data communication over a cellular communications network that allows the transmission of digital data over a voice channel using a vocoder that monitors parameters of a Levinson Durbin recursion and then uses full rate CELP if the monitored prediction error falls to below a predetermined threshold within a pre-selected number of iterations of the recursion. The system and method encode digital data to be transmitted using a continuous signal modulation technique at a selected bit rate and one or more frequencies that are selected such that the resulting modulated carrier signal is processed by the vocoder using full rate CELP as a result of the monitored prediction error. | 10-09-2008 |
20090154589 | SYSTEMS AND METHODS FOR SIGNAL MODULATION AND DEMODULATION USING PHASE - Certain embodiments provide a system for recovering data from at least one signal. The system can include an analog-to-digital converter (ADC) and in-phase/quadrature (IQ) generator component that can sample a signal recovered from a communication medium to generate a first signal sample and a second signal sample. A Fast Fourier Transform (FFT) component can process the first signal sample to generate a first signal phase and process the second signal sample to generate a second signal phase. A phase difference calculation component can determine a phase difference between the first signal phase and the second signal phase, determine a bit value represented by the signal based on the phase difference, and output the bit value to an end device coupled to the phase difference calculation component. | 06-18-2009 |
20090196373 | SYSTEM FOR INCREASING RFID TAG READER SENSITIVITY - A system for increasing the sensitivity of a receiver in an RFID tag reader. The system includes a directional coupler which receives the signal transmitted by the reader and which receives a backscatter signal from the RFID tag. The output of the directional coupler includes a transmit reference signal and a combined signal comprising the received signal and a transmit leakage signal. A first feedback loop generates an amplitude-compensated reference signal including a transmit signal component having the same amplitude as the transmit leakage signal. A second feedback loop adjusts the phase angle of the amplitude-compensated reference signal to a phase angle 180 degrees out-of-phase with the combined signal, to generate a canceling signal which effectively cancels out the transmit leakage signal component of the combined signal thereby improving the signal-to-noise ratio thereof. | 08-06-2009 |
20100215116 | WIRELESS COMMUNICATION APPARATUS - A wireless communication apparatus for performing communication using a first communication scheme which transmits a signal using amplitude shift keying and a second communication scheme which suppresses communication with others except a communication counterpart by transmitting a transmission suppression signal before communication is started. The apparatus includes: a first signal generation unit configured to generate transmission data; a modulation unit configured to generate first and second signals having different amplitudes by amplitude-shift keying the transmission data; a second signal generation unit configured to generate the transmission suppression signal having a signal length corresponding to that of the first signal; and a transmission unit configured to transmit the transmission suppression signal at the timing when the first signal is transmitted. | 08-26-2010 |
20100254477 | TRANSMISSION APPARATUS AND COMMUNICATIN SYSTEM - Disclosed herein is a transmission apparatus including a first transmission block configured to modulate a carrier-wave signal having a predetermined frequency on the basis of a first input signal, thereby outputting a first transmission signal; and a second transmission block configured to modulate a carrier-wave signal having a predetermined frequency on the basis of a second input signal, thereby outputting a second transmission signal; wherein a first input point for inputting the first transmission signal outputted from the first transmission block into a waveguide and a second input point for inputting the second transmission signal outputted from the second transmission block into the waveguide are shifted by a distance for providing a predetermined phase difference between the first transmission signal and the second transmission signal. | 10-07-2010 |
20100322338 | Method and Arrangement in a Wireless Communication Network - Method, arrangement and computer program product in a base station for transmitting two USF values and two data blocks to a terminal. The base station and the terminal are comprised within a wireless communication network. The two USF values are to be sent across the first data block and the second data block. The first data block and first parts of the two USF values are modulated with a first modulation technique and the second data block and second parts of the two USF values are modulated with a second modulation technique. The modulated data blocks and USF parts are transmitted to the terminal. Further, a method, an arrangement and a computer program product in a terminal for receiving USF values and data blocks from a base station are described. In addition, a method, an arrangement and a computer program product in a control node are described. | 12-23-2010 |
20140029690 | LOCAL OSCILLATION GENERATOR AND ASSOCIATED COMMUNICATION SYSTEM AND METHOD FOR LOCAL OSCILLATION GENERATION - A local oscillation generator includes an oscillation circuit, a frequency multiplication circuit, a mixer, and a frequency divider. The oscillation circuit provides a fundamental oscillation signal. The frequency multiplication circuit provides a first oscillation signal according to the fundamental oscillation signal. The mixer provides a mixed oscillation signal according to mixing of the fundamental oscillation signal and the first oscillation signal. The frequency divider frequency divides the mixed oscillation signal so that the local oscillation generator accordingly provides a local oscillation signal. | 01-30-2014 |
20140072072 | High Dynamic Range Transceiver - This invention uses one or more cancellation modules to eliminate the transmitter leakage at the output of the receive antenna and prior the receiver circuitry so that the received signals can be analyzed without degradation in quality due to simultaneous operation of the transmitter and receiver. Each cancellation circuit could be limited to only 30-50 dB of rejection due to component mismatches and other circuit non-idealities. To obtain further cancellation, more than one cancellation circuit can be applied after the first low noise amplifier. The output of the low noise amplifier can be repeatedly mixed with additional cancellation signals “n” number of times such that the “n” low noise amplifier is mixed with the “n | 03-13-2014 |
20140093007 | Method and Apparatus for Communication by Means of a Transformer - A method for communication by means of a transformer, which has at least a primary coil and a secondary coil, which are parts of an oscillatory circuit, wherein the oscillatory circuit is supplied on the primary side with an exciter frequency. For transmission of a signal from the secondary side to the primary side, the inductance of the secondary coil is modulated. A corresponding apparatus for performing the method is likewise provided. | 04-03-2014 |
20140140432 | Method, Receiver, Transmitter and Communication System for Phase Error Compensation - A method of compensating phase error of a received signal is disclosed. The signal comprises a symbol set comprising a plurality of symbols of a first type having an N-Quadrature Amplitude Modulation, N-QAM, signal configuration, where N is an integer larger than 4, and at least one symbol of a second type having an Amplitude and Phase-Shift Keying, A-PSK, signal configuration, wherein both the symbols of the first type and of the second type carries data and wherein the symbols of the second type also are arranged as pilot symbols for determination of phase rotation determination. A receiver and transmitter, as well as a communication system, employing the symbol set are disclosed. | 05-22-2014 |
20140211880 | METHOD AND APPARATUS FOR SUPPORTING FREQUENCY-QUADRATURE AMPLITUDE MODULATION IN WIRELESS COMMUNICATION SYSTEM - A method for generating a decoding metric in a wireless communication system includes receiving an FQAM symbol and determining transmission probabilities of FQAM symbol candidates from a received value of the FQAM symbol, wherein the transmission probabilities of the FQAM symbol candidates are determined by multiplying a probability that a QAM symbol included in the FQAM symbol is mapped to each of candidate values in one frequency and a probability that a signal is not transmitted in the other at least one frequency. An apparatus in a wireless communication system for supporting FQAM, the apparatus comprising an RF processing unit configured to receive an FQAM symbol, and a modem configured to determine transmission probabilities of FQAM symbol candidates from a received value of the FQAM symbol. | 07-31-2014 |
20140269969 | TRANSPOSITIONAL MODULATION SYSTEMS AND METHODS - Systems and methods for transpositional modulation and demodulation are provided. One such method for generating a signal includes the steps of providing a look-up table having a plurality of quarter-cycle waveforms, each of said quarter-cycle waveforms associated with a respective input level; receiving an input signal; and outputting quarter-cycle waveforms associated with levels of the received input signal. Systems for transpositional modulation are also provided. One such system for generating a signal includes a look-up table having a plurality of quarter-cycle waveforms. Each of the quarter-cycle waveforms are associated with a respective input level, and the look-up table is configured to receive an input signal, and output to quarter-cycle waveforms associated with levels of the received input signal. | 09-18-2014 |
20140286453 | SATELLITE COMMUNICATION HAVING DISTINCT LOW PRIORITY INFORMATION BROADCAST INTO ADJACENT SUB-REGIONS - A satellite communication system using hierarchical modulation to transmit a plurality of modulated signals to sub-regions within a region. Each modulated signal includes high priority content and low priority content. The system includes a satellite equipped with a plurality of satellite transmitters coupled to a plurality of antenna elements, e.g. a phased array of antenna elements. The antenna elements are utilized selectively to direct a modulated signal from a satellite transmitter to a distinct sub-region. The satellite transmitters and antenna also cooperate to broadcast the high-priority content to the region such that a ground receiver traveling from a first sub-region to an adjacent second sub-region adjacent will not experience a loss of high-priority content. First low-priority content of a first modulated signal directed to the first sub-region is independent of second low-priority content of a second modulated signal directed to the second sub-region. | 09-25-2014 |
375270000 | Vestigial or single sideband or suppressed carrier | 1 |
20090252253 | DIGITAL BROADCASTING SYSTEM AND DATA PROCESSING METHOD - A digital broadcasting system and method of processing data therein are disclosed. The present invention includes a baseband processor unit receiving a broadcast signal including mobile service data and main service data, wherein the mobile service data can configure an RS frame and wherein the RS frame includes at least one of the mobile service data and a notification message and at least one of a first signaling information describing signaling information of a virtual channel for transmitting the mobile service data and a second signaling information describing signaling information on a notification channel for transmitting the notification message, a management processor unit accessing the notification message by parsing the second signaling information from the RS frame, the management processor unit processing the accessed notification message, the management processor unit storing the processed notification message in a storage device, and a presentation processor unit outputting the processes notification message to an output device. | 10-08-2009 |