Abstract: The present invention provides a phase shift keying modulation method and a corresponding modulator, a phase shift keying demodulation method and a corresponding demodulator. The phase shift keying modulation method comprises: mapping a binary data stream to be modulated into a phase sequence comprising one or more phase symbols according to a predetermined phase shift keying modulation mode; modulating the phase symbol with a preset phase function to obtain a phase signal that changes continuously with time, wherein in each symbol cycle, a difference between a value of the phase signal at a beginning of the symbol cycle and a value of the phase signal at an end of the symbol cycle is equal to the phase symbol modulated in the symbol cycle; and obtaining a radio frequency signal by modulation based on the phase signal.

Abstract: A transmission apparatus that (i) generates a Quadrature Phase Shift Keying (QPSK) modulation signal s1(t) by applying a QPSK modulation scheme to a first data sequence, (ii) generates a 16-Quadrature Amplitude Modulation (QAM) modulation signal s2(t) by applying a 16-QAM modulation scheme to a second data sequence, (iii) generates a transmission signal z1(t) and a second transmission signal z2(t) by applying a phase hopping process, a precoding process, and a power adjust process to the QPSK modulation signal s1(t) and the 16-QAM modulation signal s2(t), wherein an average transmission power of the 16-QAM modulation signal s2(t) being the same as an average transmission power of the QPSK modulation signal s1(t), and (iv) transmits the transmission signal z1(t) from a first antenna at a first time and a first frequency and the second transmission signal z2(t) from a second antenna at the first time and the first frequency.

Abstract: At high frequencies planned for 5G and 6G, phase noise may be a limiting factor on reliability and throughput. The default modulation scheme is currently QAM. Disclosed is a more versatile demodulation method based on the amplitude and phase of the sum-signal, which is the vector sum of the two branch amplitudes of QAM. The transmitter modulates a message by sum-signal amplitude and phase. The receiver can process the received waveform according to quadrature branches as usual, and determines the branch amplitudes. The receiver then calculates, from the branch amplitudes, the sum-signal amplitude and sum-signal phase for demodulation. The receiver can thereby obtain substantially enhanced phase-noise tolerance and amplitude spacing uniformity at virtually no cost. In addition, methods are disclosed for determining specific message fault types and non-square modulation tables depending on the type of mitigation required.

Abstract: A communication chip includes an input port, a gain circuit, a correction circuit having a phase-locked loop (PLL) circuit and a return terminal, a post-processing circuit, and a switching circuit. The gain circuit includes an input terminal and a quadrature modulation circuit that operates according to a reference clock. The gain circuit gains a signal from the input terminal according to a bias voltage and outputs a gained signal. The PLL circuit generates a correction signal through synchronization according to the reference clock. The post-processing circuit obtains an input signal strength according to a correction table and a signal from a receiving terminal of the post-processing circuit. The switching circuit couples the correction signal to the input terminal and the gained signal to the return terminal in test mode and couples the input port to the input terminal and the gained signal to the receiving terminal in an operating mode.

Abstract: A pressure sensor element and a receiving circuit are formed on an IC chip. A transmitting circuit and a piezoelectric element of an actuator are respectively formed on a transmitting chip and a piezoelectric chip. The piezoelectric chip and the pressure sensor face each other separated by a distance in an airtight first space surrounded by a package main body and a base substrate. Dielectric breakdown voltage of signal transmission from the primary side to the secondary side is set by the distance. The first space is a pressure propagation region including an insulating medium capable of transmitting vibrations of the piezoelectric element as pressure. The signal transmission is performed with high insulation by the pressure generated in the pressure propagation region between components integrated in a single module by insulating the primary side and the secondary side from each other by the insulating medium of the pressure propagation region.

Abstract: A system of architecture, apparatus and calibration method is invented for high-power flexible-polarization payload for satellite communications. The system comprises onboard phase-tracked apparatus, flexible polarization mechanism, and in-orbit calibration method. The power combining and polarization performance of the phase-tracked payload is monitored on ground by measuring the cross-polarization discrimination (XPD) and/or axial ratio (AR). The high performance over the life is achieved by optimization of the XPD or AR on ground and adjusting complex gain of the transponders. The high-power flexible-polarization in-orbit-calibration payload may be applied but not limited to UHF, L, S, C, X, Ku and Ka-band high power satellite systems.

Abstract: The present application provides a method and a device for transmitting information. The method includes: the terminal device determining first quantity information, wherein the first quantity information is information about a number of code block groups comprised in a transport block, and each code block group comprises at least a code block; the terminal device determining second quantity information, wherein the second quantity information is information about a total number of bits comprised in a scheduled transport block; and; the terminal device determining information about code block groups comprised in the scheduled transport block according to the first quantity information and the second quantity information. The method for transmitting information provided by the present application can determine an appropriate amount of feedback information, reduce control signaling overhead, improve demodulation performance of control signaling, and improve system efficiency.

Abstract: According to one embodiment, a magnetic disk device includes a plurality of magnetic disks, a plurality of magnetic heads provided correspondingly to the plurality of magnetic disks and configured to carry out read/write of data from/to the magnetic disks, and a control section configured to, when the magnetic head is in a second status before the magnetic head enters the first status, change setting in such a manner as to change a first memory area of a magnetic disk corresponding to the magnetic head in the second status among memory areas constituted of the plurality of magnetic disks to a second memory area in which a write count is limited.

Abstract: A method and apparatus for communicating with a network in a wireless communication system is provided. A user equipment (UE) receives information on transmission direction of a plurality of time intervals in a first component carrier (CC) and a second CC from the network, and communicates with the network via a virtual carrier, which is either any one of the first CC or the second CC at each of the plurality of time intervals, based on the information. The second CC is shifted in time relative to the first CC by a specific time interval.

Abstract: An integrated analog to digital converting and digital to analog converting (ADDA) RF transceiver for satellite applications capable of flexibly processing high-bandwidth and low-bandwidth RF input signal(s). The RF transceiver may selectively distribute high-bandwidth RF input signals among one or more DSP pipelines for parallel processing of the RF input signals, and the RF transceiver may coherently recombine the processed signals from the one or more DSP pipelines to generate an RF output signal. The ADDA RF transceiver includes one or more ADCs, DSPs, and DACs, all on one or more ASICs, FPGAs, or modular electronic devices in a single semiconductor package. Further, the RF transceiver is radiation tolerant at the module, circuit, and/or system level for high availability and reliability in the ionizing radiation environment present in the space environment.

Abstract: A method of pre-compensating for transmitter in-phase (I) and quadrature (Q) mismatch (IQMM) may include sending a signal through an up-converter of a transmit path to provide an up-converted signal, determining the up-converted signal, determining one or more IQMM parameters for the transmit path based on the determined up-converted signal, and determining one or more pre-compensation parameters for the transmit path based on the one or more IQMM parameters for the transmit path. In some embodiments, the up-converted signal may be determined through a receive feedback path. In some embodiments, the up-converted signal may be determined through an envelope detector.

Abstract: The application discloses a transmitter with self-interference calibration ability, including: a signal generation unit for generating a signal; a CORDIC for generating an amplitude modulation signal and a phase modulation signal according to the signal; phase processing unit, for generating a frequency signal according to the phase modulation signal; a DPLL, including: a DCO, self-interference calibration unit, for generating phase compensation according to the signal, a phase difference and a reference clock; and a DCO control generation unit; and an output unit, for generating an output signal according to the amplitude modulation signal and a DCO output signal.

Abstract: A system and method of minimizing interference and retries in an environment where two or more network protocols utilize the same frequency spectrum is disclosed. A lower-power network controller is co-located with a WIFI controller. The lower-power network controller listens for a signature that may indicate the presence of a low power protocol packet, such as BLE or Zigbee. The lower-power controller checks for a waveform that is representative of a Zigbee packet prior to generating a request signal to the WIFI controller. This maximizes the likelihood that no WIFI traffic will occur while the incoming packet is being received.

Abstract: The present disclosure relates to a polar phase or frequency modulator comprising: a normalized delay circuit (602) configured to delay edges of an input carrier signal (CLK_IN) based on normalized delay control values (?i) to generate a modulated output signal (RF_OUT); and a normalized delay calculator (604) configured to receive the modulated output signal (RF_OUT) and to generate the normalized delay control values (?i).

Abstract: Systems and methods for a low-frequency radio navigation system are described. The system may include a transmitter comprising a base coded modulator configured to generate a base modulation and a data coded modulator configured to generate a data modulation; wherein the transmitter radiates a continuous, constant-power chirped-FM spread spectrum signal, comprising: the base modulation; and the data modulation, wherein the data modulation is orthogonal to the base modulation. The system may also include a receiver comprising a digital signal processor, wherein at least one matched filter coupled to the digital signal processor, the at least one matched filter configured to decode said base modulation and data-encoded modulation and provide a correlation function for received signals received from at least three geographically-spaced transmitters.

Abstract: The disclosed systems, structures, and methods are directed to a superposition based transceiver. The configurations presented herein employ a plurality of encoders configured to encode a plurality of input digital data streams, wherein each of the plurality of input digital data streams operates at different data rates, a plurality of modulators configured to modulate the plurality of encoded digital data input streams. In addition, a plurality of transmitter filters configured to perform up-sampling and filtering of the plurality of modulated digital data streams, and a signal mixer configured to combine the plurality of up-sampled and filtered digital data streams into a single aggregate digital data stream in a manner such that the single aggregate digital data stream contains spectral characteristics that substantially conform to both a central area and a skirt area of a unified spectral emission mask, as specified by European Telecommunications Standards Institute (ETSI).

Abstract: A transmission device includes a data generation unit to generate a data symbol, a linear processing unit to generate an additional symbol, a power conditioning unit to perform power conditioning on the additional symbol, a frequency-domain multiplexing unit to arrange the additional symbol after the power conditioning and the data symbol along a frequency axis, a conversion unit to convert a signal arranged along the frequency axis by the frequency-domain multiplexing unit into a time domain signal, and a transmission processing unit to transmit the time domain signal. The linear processing unit generates the additional symbol to cause a data portion in a predetermined position in a block, which is a transmission unit of the time domain signal, to be set as a predetermined data group.

Abstract: Quadrature Amplitude Modulation (QAM) apparatus and systems for use in providing images or video via a wired connection in a video inspection system are disclosed.

Abstract: A bit interleaver, a bit-interleaved coded modulation (BICM) device and a bit interleaving method are disclosed herein. The bit interleaver includes a first memory, a processor, and a second memory. The first memory stores a low-density parity check (LDPC) codeword having a length of 16200 and a code rate of 3/15. The processor generates an interleaved codeword by interleaving the LDPC codeword on a bit group basis. The size of the bit group corresponds to a parallel factor of the LDPC codeword. The second memory provides the interleaved codeword to a modulator for quadrature phase shift keying (QPSK) modulation.

Abstract: A stable modulation-index Bluetooth (BT) transmitter circuit includes a baseband modulator circuit to generate a baseband BT signal. An intermediate frequency (IF) circuit adds a frequency offset to the baseband BT signal with a low IF and generates a modulated signal. A digital-to-analog converter (DAC) converts the modulated signal to an analog signal that is upconverted using a voltage controlled oscillator (VCO). The baseband frequency offset is subtracted from the corresponding radio-frequency (RF) signal by reducing the local oscillator (LO) frequency by the same amount. This has the effect of modulating the carrier leakage away from the center frequency of the transmitted BT signal. The resulting RF signal is transmitted to a receiver.

Abstract: A method for transmitting a signal by an apparatus having a plurality of antennas in a wireless communication system, according to one embodiment of the present invention, comprises the steps of: mapping complex modulation symbols to L layers; sequentially applying a unit matrix U, a diagonal matrix D, and a precoding matrix W to the symbols which have been mapped to the L layers; and mapping symbols which have been mapped to DMRS ports by applying W, D and U, wherein W is one of M sets of precoders, each of the M sets of precoders comprising a plurality of column vectors, and wherein if the number of DMRS ports is smaller than M*L, the M sets of precoders include at least one identical column vector.

Abstract: A method and apparatus for receiving a reduced peak to average power ratio signal is disclosed. The method includes receiving a signal, the signal being processed prior to transmission to reduce peak to average power ratio, determining a processing mode used to reduce the peak to average power ratio of the received signal, and reducing the amplitude level for a portion of the received signal using constant modulus clipping if the processing mode includes a two-dimensional constellation extension. The apparatus includes a processing circuit that receives a signal, the signal being processed prior to transmission to reduce peak to average power ratio, and a limiter circuit that determines a processing mode used to reduce the peak to average power ratio of the received signal and reduces the amplitude level for a portion of the received signal using constant modulus clipping if the processing mode includes a two-dimensional constellation extension.

Abstract: The present disclosure relates to a polar phased-array transmitter and a mobile terminal. One example mobile terminal includes a baseband chip, the polar phased-array transmitter, and an antenna array. The baseband chip is configured to generate a quadrature digital baseband signal. The polar phased-array transmitter is configured to perform quadrature-to-polar conversion on the quadrature digital baseband signal to generate n amplitude signals and n phase signals, separately perform phase modulation and phase shifting on the n phase signals by using a local oscillator signal to obtain n phase modulation signals, and perform amplitude modulation and power amplification on the n phase modulation signals by using the amplitude signals to obtain n radio frequency signals. n is a natural number greater than 1. The antenna array is configured to obtain the n radio frequency signals from the polar phased-array transmitter, and transmit the n radio frequency signals.

Abstract: A method for reducing a peak to average power ratio (PAPR) of an orthogonal frequency division multiplexing (OFDM) signal. A first signal in the frequency domain is processed to generate a second signal by performing a modular permutation on the first signal according to a modular permutation index, and/or by performing a cyclic shift on the first signal according to a cyclic shift parameter. The second signal is then mapped to a number of tones, and transformed into a time-domain signal for transmission. The modular permutation index and/or the cyclic shift parameter are selected so that the signal for transmission has a PAPR that satisfies a predefined PAPR criteria.

Abstract: Methods, apparatuses, and computer readable media for resource allocation signaling in a high efficiency wireless local area network (WLAN) are disclosed. A receiver may receive, at a first station, a transmission frame that includes a WLAN signaling field decodable by a plurality of stations. The receiver may identify, in a station-specific portion of the WLAN signaling field, an order for a plurality of station-specific information blocks associated with the plurality of stations. The receiver may determine a number of spatial streams allocated to the first station based at least in part on the identified order for the plurality of station-specific information blocks.

Abstract: A bit interleaver, a bit-interleaved coded modulation (BICM) device and a bit interleaving method are disclosed herein. The bit interleaver includes a first memory, a processor, and a second memory. The first memory stores a low-density parity check (LDPC) codeword having a length of 16200 and a code rate of 3/15. The processor generates an interleaved codeword by interleaving the LDPC codeword on a bit group basis. The size of the bit group corresponds to a parallel factor of the LDPC codeword. The second memory provides the interleaved codeword to a modulator for quadrature phase shift keying (QPSK) modulation.

Abstract: A digital quadrature architecture is presented that employs switched current digital power amplifiers and uses a digital class-B input code profile in combination with non-overlapping LO signals to overcome the low efficiency problems of conventional quadrature architectures. By employing digital class-B signals, the number of I/Q cells is reduced to half and the need for extra processing of the sign bits is eliminated in the transmitters, thereby improving the efficiency.

Abstract: This disclosure relates to an apparatus, system, and method for generating uplink transmissions using a polar architecture including a phase locked loop with potential for two point injection. According to some embodiments, frequency resources allocated for a transmission may be determined. A cartesian baseband signal may be generated for the uplink transmission. The cartesian baseband signal may be converted to a polar baseband signal, including a baseband phase signal and an amplitude signal. Modulation parameters, potentially including whether to use one point injection or two point injection with a phase locked loop, may be determined. The baseband phase signal may be upconverted to an RF phase signal according to the determined modulation parameters. The RF phase signal may be amplified according to the amplitude signal to produce an RF signal. The RF signal may be transmitted.

Abstract: A multiphase transmitter including a reactive combiner for combining amplified pulse modulated signals generated by multiple power amplifiers of the transmitter. In some embodiments, the reactive combiner is configured to inhibit odd order harmonics of the amplified pulse modulated signals in a power efficient manner.

Abstract: Apparatus and methods for transmit power control in wireless communication systems are provided. In one aspect, a wireless communication system includes a transmit chain that generates a transmit signal based on a data signal having a time-varying signal envelope, a power amplifier that amplifies the transmit signal, and a transmit chain controller that generates a first power control signal and a second power control signal that control an adjustable power level of the transmit chain. The transmit chain controller includes an error extractor that generates an error signal based on comparing an output signal power of the power amplifier to the time-varying signal envelope. The transmit chain controller further includes a control signal generator that generates the first power control signal and an adjustment signal based on estimating the error signal, and that generates the second power control signal based on the error signal and the adjustment signal.

Abstract: A carrier aggregation controller for providing an aggregated baseband signal from a plurality of baseband signals is provided. The controller comprises an accumulating memory, a selector and a time domain transformer. The selector is configured to add at least a first list of frequency domain samples obtained for the first baseband signal to first consecutive locations in the accumulating memory centered at a first preset location associated with the first baseband signal, and a second list of frequency domain samples obtained for the second baseband signal to second consecutive locations in the accumulating memory centered at a second preset location associated with the second baseband signal. The time domain transformer is configured to apply at least an inverse discrete Fourier transform to the frequency domain samples accumulated in the accumulating memory, obtaining the aggregated baseband signal.

Abstract: Disclosed in the present disclosure are a method and system for measuring interference signals in carrier signals. The method comprises: receiving multiple valid samples of the carrier signals; based on the multiple valid samples of the carrier signals, gaining value of constant part and mean square error of zero mean part in the interference signals through iterative calculation; calculating the total power value of the interference signals. Since considering the constant part in the interference signals, the measurement method is suitable in the case that the interference signals in the carrier signals is non-zero mean value, and the obtained measurement result of the interference signals will be more accurate than the result through the existing method.

Abstract: Hybrid ARQ is employed in a multi-carrier communication system for retransmission of erroneous packets by taking advantage of time/frequency/space diversity and by combining ARQ functions at physical layer and MAC layers, making the multi-carrier system more robust in a high packet-error environment.

Abstract: Embodiments are provided herein for implementing a user cooperation protocol for interference alignment (IA) in wireless local area network (WLAN) or a Wi-Fi hotspot. The embodiments allow collecting knowledge of the channels from user stations (STAs) and sending this information to the corresponding access points (APs) in the network. This information is then used by the APs to pre-code their signals such as to remove interfering signals to non-intended STAs. An AP transmits to the STAs a group identifier (GrpID) indicating an order of STAs for transmitting channel state information (CSI) and an AP index indicating an order of STA groups of the APs for transmitting the CSI. When a STA detects a CSI transmission from another STA preceding the STA in the order of transmission as indicated by the AP index and GrpID, the STA transmits its CSI.

Abstract: A transmitter according to the present invention includes a level detector that detects the level value of an input signal, from among a predetermined number of level values; an upstream-side signal adjusting unit that amplifies the input signal and shifts the input signal for an offset amount based on an output signal of the level detector; a digital-sigma modulator having a quantizer that quantizes an output signal of the upstream-side signal adjusting unit with a predetermined number of bits, and a downstream-side signal adjusting unit that amplifies an output signal of the delta-sigma modulator and shifts the output signal of the delta-sigma modulator for an offset amount based on the output signal of the level detector.

Abstract: A transmitting apparatus and transmission method are capable of easily and correctly mixing an in-phase component and a quadrature-phase component in a quadrature modulator. A local signal with a duty ratio of 25% or smaller is generated without using frequency which is a multiple of frequency of the local signal. Without providing switches in series to the outputs of I and Q amplifiers, a duty ratio of 25% or less is obtained. for the local signal, and class-D unit amplifiers are operated such that one of the I amplifier and the Q amplifier is connected to the output side in any state regardless of whether an output power control signal is at an on-level or an off-level. In producing the 25% duty ratio, a local signal with a 50% duty ratio is converted so as to have a duty ratio of 25% by I and Q duty converters.

Abstract: Various aspects of an approach for generating a large number of balanced weight sequences such as balanced Hamming weight preamble sequences are described herein. The approach provides for the generation of balanced weigh sequences that need to satisfy requirements such as minimal cross-correlation with delayed versions of itself and other sequences in the allowed set. The approach includes creating a set of symbol groups that include balanced properties from which a sequence may be generated by selecting therefrom.

Abstract: A system for reducing in-phase and quadrature-phase (I/Q) impairments includes first, second, third, and fourth programmable registers for storing respective first, second, third, and fourth values, first and second finite impulse response (FIR) filters having respective first and second sets of filter taps, and first and second adders. The first FIR filter receives an I input signal and generates first and second intermediate output signals based on the first and second values for I and Q channels, respectively. The second FIR filter receives a Q input signal and generates third and fourth intermediate output signals based on the third and fourth values for the I and Q channels, respectively. The first and second adders receive the first and second, and the third and fourth intermediate output signals, respectively, and generate compensated I and Q output signals for the I and Q channels.

Abstract: In an angle modulated radio transmitter, the total power is the same when modulated or unmodulated. Angle modulation produces multiple sideband pairs. The power in the sidebands is derived from the carrier. When a complex modulating waveform is used, the power (and therefore the amplitude) of the carrier varies. A system and method is provided for dramatically minimizing, to nearly zero, the bandwidth needed to transmit digital information using sideband suppression of angle modulated signals. The systems described use various techniques to suppress sideband pairs, leaving the carrier signal. The amplitude variations of the carrier are used to convey information. In some examples, techniques are used to filter and/or phase out one or more sideband pairs, leaving the carrier signal.

Abstract: Embodiments of a circuit are described. In this circuit, a modulation circuit provides a first modulated electrical signal and a second modulated electrical signal, where a given modulated electrical signal, which can be either the first modulated electrical signal or the second modulated electrical signal, includes minimum-shift keying (MSK) modulated data. Moreover, a first phase-adjustment element, which is coupled to the modulation circuit, sets a relative phase between the first modulated electrical signal and the second modulated electrical signal based on a phase value of the first phase-adjustment element. Additionally, an output interface, which is coupled to the first phase-adjustment element, is coupled to one or more antenna elements which output signals. These signals include a quadrature phase-shift-keying (QPSK) signal corresponding to the first modulated electrical signal and the second modulated electrical signal.

Abstract: A method for improving communication sensitivity by a wireless communication device is described. The method includes obtaining a string of bits. The method also includes mapping each bit in the string of bits to a pre-allocated bit pattern to create a series of concatenated pre-allocated bit patterns. The method further includes generating a modulated signal based on the series. The method additionally includes transmitting the modulated signal.

Abstract: For use in a transmitter in a wireless network, a transmitter apparatus is configured for digital multi-level outphasing. The apparatus includes a bandwidth reduction (BWR) modulator block configured to receive a phase modulated carrier and reduce a bandwidth of the phase modulated carrier using amplitude modulation. The apparatus also includes an outphasing modulator block configured to receive the reduced-bandwidth phase modulated carrier and an amplitude modulated signal, and convert the reduced-bandwidth phase modulated carrier into a plurality of phase modulated signals. The apparatus further includes an amplification stage comprising a plurality of power transistors configured to amplify the phase modulated signals.

Abstract: An adaptive coding and modulation (ACM) apparatus and method for a forward link in satellite communication is provided. The ACM apparatus may include a receiving unit to receive a signal-to-noise ratio (SNR) of a received signal, a determination unit to determine whether the SNR of the received signal is less than or equal to a threshold value, and a processing unit to execute a channel prediction algorithm when the SNR of the received signal is determined to be less than or equal to the threshold value.

Abstract: A digital polar modulator (DPM) for transforming a baseband signal into a modulated digital modulator output signal comprises an input unit and two low-pass delta-sigma modulators, a first one being connected downstream from the first input part and configured to provide at its output a first pulse train in dependence on an amplitude- modulating baseband signal component, and a second one being connected downstream from the second input part and configured to provide at its output a multilevel quantized signal in dependence on a phase modulating baseband signal component; a multiphase generator, which is configured to provide a set of square-wave carrier signals having a common carrier frequency and exhibiting discrete phase shifts with respect to each other; a multiplexer, which is configured to provide a multiplexer output signal that is formed by switching, in dependence on a signal received at a select input as a function of time, between selected ones of the carrier signals; and a combiner unit.

Abstract: Phase rotation for preambles within multiple user, multiple access, and/or MIMO wireless communications. An appropriately designed phase rotation vector and/or appropriately designed cyclic shift delays (CSDs) are applied to respective sub-band components of the preamble. With appropriately designed CSDs, certain fields within the preamble are not modified. For example, a legacy short training field (L-STF) of the preamble is not changed when using appropriately designed CSDs. The respective CSDs may be implemented as integer multiples of a common CSD (e.g., 0×CSD, 1×CSD, 2×CSD, etc. such that one of the values of such a CSD vector may be zero [0], another may be the common CSD itself, etc.). Also, by employing an appropriately designed phase rotation vector and integer multiples of a CSD to a preamble, the respective peak to average power ratio (PAPR) between different respective fields within the preamble may be minimized.

Abstract: The present invention provides a method for modulating a navigation signal, comprising: multiplying a data channel difference signal between upper and lower sidebands by a sine binary subcarrier to obtain an odd timeslot baseband signal of a branch Q, and multiplying a data channel sum signal of the upper and lower sidebands by a cosine binary subcarrier to obtain an odd timeslot baseband signal of a branch I of the data channel; multiplying a pilot channel difference signal between the upper and lower sidebands by the sine binary subcarrier to obtain an even timeslot baseband signal of the branch Q, and multiplying a pilot channel sum signal of the upper and lower sidebands by the cosine binary subcarrier to obtain an even timeslot baseband signal of the branch I; and performing QPSK modulation on the baseband signals of the branch I and branch Q to obtain a TD-AltBOC modulation signal.

Abstract: Disclosed is a method of transmitting dual digital signals through a single antenna. The method includes receiving, by a transmitter, a first data stream and a second data stream which use the same carrier frequency, modulating, by the transmitter, each of the first data stream and the second data stream, lowering, by the transmitter, a power level of the modulated second data stream, combining, by the transmitter, the modulated first data stream and the second data stream with the lowered power level, and transmitting, by the transmitter, the added first data stream and second data stream to a single antenna in the same channel.

Abstract: An ultra-wide band frequency modulator is disclosed. The frequency modulator includes a direct modulation phase lock loop that receives a small component. The frequency modulator also includes a delay module that produces a plurality of delay lines. The frequency modulator further includes an edge selector that receives a large component and the plurality of delay lines.

Abstract: An optical homodyne communication system and method in which a side carrier is transmitted along with data bands in an optical data signal, and upon reception, the side carrier is boosted, shifted to the center of the data bands, and its polarization state is matched to the polarization state of the respective data bands to compensate for polarization mode dispersion during transmission. By shifting a boosted side carrier to the center of the data bands, and by simultaneously compensating for the effects of polarization mode dispersion, the provided system and method simulate the advantages of homodyne reception using a local oscillator. The deleterious effects of chromatic dispersion on the data signals within the data bands are also compensated for by applying a corrective function to the data signals which precisely counteracts the effects of chromatic dispersion.

Abstract: A method, device and system for complex carrier modulation are provided in the disclosure, wherein e?i?t or ei?t is used as a carrier frequency to perform carrier modulation on a to-be-carried signal. The modulated signal transmitted in a medium is a rotating complex signal. The method can enable right and left frequency bands to carry independent information. Therefore the spectrum utility ratio is improved. Employing the method for complex carrier modulation provided in the disclosure can use the right and left frequency spectrum resources adequately, and the loss of signal energy is small, therefore the capacity of a channel is improved greatly.