32 results about "Bpsk modulation" patented technology

The invention discloses a finite geometric code decoding method and system based on a generalized check matrix, and relates to the communication technology, and the method comprises the following steps: constructing a corresponding generalized check matrix according to an algebraic structure of a multi-step large number logic decodable finite geometric code; sending a finite geometric code sequence, transmitting the sequence after coding and BPSK modulation, and receiving a posterior probability log-likelihood ratio sequence by a receiving end; and carrying out iterative decoding on the finite geometric code received by the receiving end based on the constructed generalized check matrix. According to the invention, a new generalized check matrix is constructed according to the algebraic structure of the finite geometric code, and multi-step large-number logic iterative decoding is carried out on the finite geometric code based on the matrix, so that the iterative decoding performance of the multi-step large-number logic decodable finite geometric code is improved.

The invention relates to an unmanned aerial vehicle uplink anti-forwarding interference method, and belongs to the technical field of unmanned aerial vehicle measurement and control communication anti-interference. Comprising the following steps: constructing a signal source module, performing BPSK modulation on a generated random binary sequence, and adding a serial number at a data frame header to distinguish a data instruction sending sequence; the method comprises the following steps: constructing a channel 1 to transmit an information source signal, constructing a channel 2 to introduce forwarding interference, constructing a receiver to filter and demodulate the received signal, and then executing an instruction contained in the signal; an anti-forwarding interference module is constructed and comprises a serial number judgment module, a secret key authentication module, a secret key replacement module and an instruction serial number judgment module, an instruction frame header serial number is compared at an execution end to determine whether the instruction frame header serial number is a forwarding signal, the problem that an unmanned aerial vehicle airborne end repeatedly executes ground instructions is solved, and the instruction serial number is recycled within a certain digit; and the key is replaced once after each cycle is ended. According to the invention, the bit error rate of information transmission can be reduced, and the anti-interference capability of an unmanned aerial vehicle measurement and control link is improved.

DFT spreading is applied to a sequence of symbols to generate a DFT-spread sequence of symbols. The DFT-spread sequence of symbols is frequency-division multiplexed with a reference signal sequence to generate a multiplexed sequence, and the DFT-spread sequence of symbols and the reference signal sequence are recoverable from demultiplexing the multiplexed sequence. Further processing, such as a transform to convert to time domain and / or spectral shaping, may be applied in some embodiments. The symbols may be modulation symbols to which data bits are mapped, in binary phase-shift keying (BPSK) modulation, pi / 2-BPSK modulation, quadrature phase-shift keying (QPSK) modulation, quadrature amplitude modulation (QAM) or offset-QAM (OQAM), for example. Embodiments may be applied in conjunction with any of different types of reference signals, such as a demodulation reference signal (DM-RS), a phase tracking reference signal (PT-RS), or a channel state information reference signal (CSI-RS), or different types of reference signal sequences.

The present disclosure relates to a method and apparatus for sending uplink control information, a method and apparatus for receiving uplink control information, a user equipment, a base station, and a computer-readable storage medium. The method for sending uplink control information includes: simultaneously sending first HARQ feedback information and second HARQ feedback information to a base station via a PUCCH; wherein the first HARQ feedback information is 1-bit high-priority HARQ feedback information, the second HARQ feedback information is 1-bit low-priority HARQ feedback information, the first HARQ feedback information and the second HARQ feedback information are modulated using QPSK, and the first set of modulation symbols when the second HARQ feedback information is NACK and the first HARQ feedback information is NACK is the same as the second set of modulation symbols when the second HARQ feedback information is NACK and the first HARQ feedback information is ACK is the same as the first set of modulation symbols when only the first HARQ feedback information is sent and BPSK modulation is used, and the first set of modulation symbols when the first HARQ feedback information is NACK and the first HARQ feedback information is ACK is the same. The method disclosed herein retransmits low-priority data when it is lost.

Methods and apparatus, including computer program products, are provided for pi / 2 BPSK initial access. In some example embodiments, a method can be provided that includes receiving, at a user equipment, information indicating network support for initial network access based on a pi / 2 binary phase shift keying (pi / 2-BPSK) modulation and coding scheme; and in response to the received system information, performing initial network access by at least sending a connection request based on the pi / 2-BPSK modulation and coding scheme. Related systems, methods, and articles of manufacture are also described.

The application discloses a kind of distance gating anti-interference optical frequency domain reflection distributed measuring device and method, its device includes frequency-sweeping laser light source, first optical coupler, Mach-Zehnder modulator, circulator, detection optical fiber, polarization controller, second optical coupler, balanced photodetector and data measurement unit.Wherein, Mach-Zehnder modulator is configured as using pseudo-random spread spectrum coding technology to the input probe light is BPSK modulation.Through the above device and method, the application successfully solves the contradiction between long distance measurement and fast frequency sweep in traditional OFDR difficult to obtain.

The invention provides an adaptive modulation switching method for satellite-ground laser communication. The performance of a communication system is improved by using 16QAM (Quadrature Amplitude Modulation) and BPSK (Binary Phase Shift Keying) modulation adaptive switching; the method comprises the following steps: firstly, carrying out polarization code coding on an information sequence, scattering the sequence through an interleaver, and then modulating the sequence through a modulator and sending the modulated sequence to a satellite-ground laser communication channel. An atmospheric turbulence estimation module is introduced at a receiving end, estimated atmospheric channel state information is fed back to a sending end through an estimated value of satellite-ground laser communication atmospheric turbulence intensity, then a modulation mode of the sending end is switched according to a threshold value, and low-time-delay reliable transmission of satellite-ground communication laser communication is achieved.

The present invention belongs to the field of free-space laser communication, and in particular, is a relay laser communication coding method for FSO systems, comprising the following steps: Step 1, obtaining a sequence to be coded at a source node, and polarization coding of K=k+m codewords as information bits; Step 2, using an interleaver to change the information position to the maximum extent and resist long-segment errors; Step 3, sending the codeword sequence at the source node to the destination node and the relay node via BPSK modulation. The present invention integrates cooperative communication with channel coding technology to achieve efficient cooperative transmission of Polar codes in a cooperative relay system to achieve the capacity of the relay system. A single link cannot resist channel interference well, and cooperative technology can effectively combat fading, thereby improving the ability of the relay system to resist continuous burst errors, and combining channel coding and cooperative diversity technology to achieve the capacity of the relay system.

The invention discloses an underwater laser communication transmitter compatible with multiple modulation formats, which belongs to the field of communication transmitters and comprises a seed source module, a signal modulation module, a power amplification module, an LBO wavelength conversion module and a small-angle collimation transmitting module. The seed source module is a 1064nm DBR (Distributed Bragg Reflector) narrow linewidth laser; the signal modulation module comprises a modulator, and switching of OOK modulation formats, BPSK modulation formats and DPSK modulation formats is achieved by adjusting bias points; the power amplification module adopts a main oscillation power amplification structure and comprises two pre-amplification stages and two main amplification stages; the LBO wavelength conversion module is used for carrying out frequency multiplication on 1064nm light to obtain 532nm green light, and the output power is not less than 7W; and the small-angle collimation transmitting module compresses the green light and then outputs the compressed green light.

The invention provides a communication method and communication equipment. The method comprises the steps that a first device sends a first signal and a second signal on different transmission layers to a second device through the same antenna, the first signal and the second signal are data subjected to DFT-S-OFDM processing, the modulation mode used for modulating the first signal and the second signal in the DFT-S-OFDM processing process is pi / 2-BPSK, and the modulation mode used for modulating the first signal and the second signal in the DFT-S-OFDM processing process is Pi / 2-BPSK. A phase difference of pi / 2 exists between the first signal and the second signal. Through the combination of DFT and a pi / 2-BPSK modulation mode, the PAPR can be effectively reduced on the basis of expanding the coverage area, and the first device sends the first signal and the second signal of different transmission layers through the same antenna and forms a pi / 2 phase difference, so that the second device can distinguish the first signal and the second signal transmitted on the same antenna, and the transmission efficiency of the first device is improved. And the spectrum efficiency is further improved on the basis of not increasing the PAPR.

Methods, systems, and devices for wireless communications are described. The described techniques provide for a user equipment (UE) to communicate using π / 2 binary phase shift keying (BPSK) modulation according to extended coding rates. In some cases, the UE may receive configuration information that supports modulation orders for π / 2 BPSK modulation extended to include modulation orders otherwise only configured for quadrature phase shift keying (QPSK) modulation. Further, the UE may support dynamic switching between π / 2 BPSK and QPSK modulation. For example, the UE may transmit or receive control signaling indicating a modulation order for an uplink transmission, where the UE or a network entity may determine which modulation scheme and order to use according to communication parameters associated with the uplink transmission, the UE, or both.

The invention relates to the technical field of electric power communication and battery management, and discloses a BPSK communication and battery impedance measurement method and system based on multi-sine disturbance, and the method comprises the steps: a communication channel between a transmitting end and a receiving end is realized through power line communication, a BPSK modulation signal and a plurality of sine disturbance signals with independent frequencies are synchronously generated at the transmitting end, a PWM duty ratio is calculated, and a BPSK modulation signal and a plurality of sine disturbance signals with independent frequencies are generated at the receiving end; after being superposed, the signals are injected into a battery side through a power converter, and a switching device of the power converter is driven through a PWM duty ratio; sampling a communication signal at a receiving end, generating a demodulation reference signal, and judging a sending bit of the communication signal; and acquiring a voltage signal and a current signal of the power converter under the sine disturbance signal, extracting an orthogonal component under each frequency of the sine disturbance signal, and calculating apparent power and a phase angle according to the orthogonal component so as to calculate the battery impedance. Real-time measurement of power line communication and battery impedance can be realized at the same time, power interference is reduced, and the integration level is improved.

This invention relates to the field of channel communication technology, specifically disclosing a method for improving the communication performance of plasma sheath channels based on fountain code soft decoding. After establishing a plasma channel model, the amplitude attenuation function follows a log-normal distribution, and the phase shift function follows a Gaussian distribution. The probability densities of the amplitude attenuation function and the phase shift function are calculated respectively. Then, combined with the plasma channel model, the conditional probability density of the plasma sheath channel for matched filtering of the received signal is calculated. The log-likelihood ratio in the plasma sheath channel under BPSK modulation of ideal channel information is calculated, as well as the likelihood probability value and log-likelihood ratio of the received signal under unknown plasma sheath channel parameters. This determines the initial values ​​for iteration, which are then used for fountain code soft-decision decoding. This invention enables the reuse of usable information in discarded fountain code packets, thereby further improving the utilization rate of fountain code packets and enhancing the overall communication efficiency of the plasma sheath channel.

The invention provides an inter-station satellite bidirectional time forecasting method, and belongs to the technical field of time calibration and forecasting. According to the method, a synchronous orbit GEO satellite is used as a forwarding node of a space segment, two stations respectively carry out BPSK modulation on local time mark signals to form frequency signals, and the frequency signals are transmitted to an opposite end through power amplification. In the data processing process, an inter-station time comparison result is calculated according to an existing model, then modeling and learning training are carried out on measured data by using an LSTM model, and finally a predicted inter-station time comparison sequence is output to be used for correcting inter-station time deviation of the next period and forecast of various clock differences.

The invention discloses a wireless communication hidden security modulation method based on spatio-temporal chaos, which comprises the following steps: firstly, an information sending end generates a spatio-temporal chaos two-dimensional signal matrix, performs dispersion modulation based on the spatio-temporal chaos two-dimensional signal matrix, and sends the spatio-temporal chaos two-dimensional and the information receiving end generates a spatiotemporal chaos two-dimensional signal matrix and the received dispersion modulation signal according to the same initial parameters as the sending end, dispersion demodulation is performed by applying an operation mode opposite to the sending end, and a demodulated signal is obtained. According to the scheme of the invention, the advantages of BPSK modulation and spatio-temporal chaos are organically fused, the characteristics of spatio-temporal chaos are fully utilized, signals are dispersed, a receiving end performs demodulation dispersion in an operation mode opposite to that of a sending end, and then spatio-temporal chaos dispersion demodulation can be realized through BPSK signal demodulation. By means of the method, the bit error rate close to the BPSK theoretical value can be obtained, communication concealment is achieved while the communication capacity is kept, and the method has high reference value for application of the physical layer security technology based on spatio-temporal chaos.

The invention discloses a signal modulation method for spaceflight. Data are modulated based on a direct sequence spread spectrum and Gaussian minimum frequency shift keying modulation technology. Compared with DSSS-BPSK modulation, satellite EMC of multi-frequency-point emission is improved, the frequency spectrum captured by PMF-FFT is more characteristic, the phenomenon of mistaken capturing is not prone to occurring, and due to the fact that the single-path code rate is half of the DSSS-BPSK, the chip migration effect is easy to eliminate.

This application proposes a method, computer device, and storage medium for decoding NAND Flash data. The method includes: receiving a modulation request for an original codeword and performing BPSK modulation on the original codeword to obtain a first value and a second value; adding noise to the first and second values ​​according to a preset Gaussian distribution to obtain a target Gaussian distribution and a target codeword; when there are overlapping regions in the target Gaussian distribution, calculating the boundaries of the overlapping regions to obtain a target boundary to obtain a target region; dividing the target region into LLR regions to obtain thresholds for multiple LLR regions; performing LLR quantization on the target codeword according to the thresholds of the multiple LLR regions to obtain LLR information of the target codeword; and inputting the LLR information of the target codeword into LDPC for decoding to obtain decoded information. This application makes the decoding error correction performance obtained by LDPC simulation more reliable, practical, and closer to the decoding error correction performance in NAND Flash module applications.

The disclosure provides a communication method, a communication device and a communication system, and relates to the technical field of communication. The method comprises the following steps: a terminal receives first information sent by a network device, and then determines a MCS index range corresponding to a first modulation mode in a MCS table according to the first information. For example, for a higher code rate π / 2-BPSK modulation mode, the terminal can accurately determine the MCS index range of the π / 2-BPSK modulation mode in the MCS table. Subsequently, the terminal can accurately use the higher code rate π / 2-BPSK modulation mode for uplink data transmission according to the indication of the network device, effectively reduces the PAPR, thereby improving the spectral efficiency and improving the uplink coverage.

Various aspects of the present disclosure relate to MCS determination for PUSCH transmission. In an aspect, a UE determines a first modulation and coding scheme (MCS) index table based on a physical uplink shared channel (PUSCH) type of a PUSCH transmission. A number of entries supporting π / 2 binary phase shift keying (BPSK) modulation in the first MCS index table is larger than a number of entries supporting π / 2 BPSK modulation in a second MCS index table. The first MCS index table and the second MCS index table are applied for a same PUSCH type. The UE transmits, to a network entity, the PUSCH transmission using a modulation order and a target code rate. The modulation order and the target code rate are determined based on the first MCS index table and an indication indicative of an MCS index for the PUSCH transmission.

This invention discloses a method for estimating the physical layer four-phase complex scrambling code sequence for low-Earth orbit satellite communication systems, belonging to the field of satellite communication technology. The method includes: selecting a target signal subjected to four-phase physical layer complex scrambling based on inter-frame BPSK modulation and intra-frame QPSK modulation criteria to obtain an equivalent sequence; analyzing the periodicity of the equivalent sequence to obtain an estimated equivalent sequence, then performing polynomial matching to obtain the generator polynomial of the estimated equivalent sequence, further analyzing to obtain the equivalent sequence generation rule and generating a local equivalent sequence; traversing according to the equivalent sequence generation rule to generate candidate adjoint sequences, combining them with the estimated equivalent sequence to obtain a candidate scrambling code sequence; descrambling the target signal according to the candidate scrambling code sequence, and if the descrambled target signal meets the decision condition, outputting the candidate scrambling code sequence as the scrambling code sequence. This invention solves the problem in blind signal demodulation where the sample phase transformation caused by the four-phase physical layer complex scrambling of the original signal prevents effective demodulation of the target signal.

The application is suitable for the field of wideband digital communication technology, and relates to an improved partial transmission sequence method for BPSK modulation. The method utilizes the signal characteristics of BPSK modulation, introduces a new phase factor selection scheme, simplifies the calculation process of the time domain candidate signal of the PTS scheme, and enables the transmitting end to not transmit any sideband information. With the help of the new phase factor sequence, the corresponding partial transmission sequence method of the BPSK modulation signal can effectively reduce the calculation complexity, and meanwhile, the same channel transmission performance as the traditional scheme is obtained without carrying sideband information. In addition, very excellent peak-to-average ratio performance can also be obtained.

Methods and apparatus, including computer program products, are provided for pi / 2 BPSK initial access. In some example embodiments, there may be provided a method that includes receiving, at a user equipment, information indicating network support of an initial network access based on a pi / 2 binary phase shift keying (pi / 2-BPSK) modulation and coding scheme; and performing, in response to the received system information, the initial network access by at least sending a connection request based on the pi / 2-BPSK modulation and coding scheme. Related systems, methods, and articles of manufacture are also described.

Methods, systems, and devices for wireless communications are described. The described techniques provide for a user equipment (UE) to communicate using binary phase shift keying (BPSK) modulation according to extended coding rates. In some cases, the UE may receive configuration information that supports modulation orders for BPSK modulation extended to include modulation orders otherwise only configured for quadrature phase shift keying (QPSK) modulation. Further, the UE may support dynamic switching between BPSK and QPSK modulation. For example, the UE may transmit or receive control signaling indicating a modulation order for an uplink transmission, where the UE or a network entity may determine which modulation scheme and order to use according to communication parameters associated with the uplink transmission, the UE, or both.

A baseband signal processing method based on an FPGA comprises a spread spectrum module, a forming filtering module, a modulation module, a matched filtering module, a pseudorandom sequence synchronous de-spreading module and a carrier synchronous demodulation module. An FPGA is used as a baseband signal processing platform, a spread spectrum module adopts an improved LC chaos sequence to carry out direct sequence spread spectrum to improve the confidentiality of a communication system, a forming filtering module is used for eliminating intersymbol interference, a modulation module carries out BPSK modulation to improve the anti-interference performance of the communication system, and a matched filtering module is used for reducing the bit error rate. And the original signal is synchronized and recovered through the pseudo-random sequence synchronization module and the carrier synchronization module. According to the invention, baseband signal processing of the communication system is realized through the FPGA, which is more convenient and flexible, various environmental interferences and man-made interferences existing at present can be effectively solved, and the anti-interference performance and confidentiality of a software radio communication system are greatly improved.

The invention discloses a code selection N-path filter which comprises an eight-path parallel processing structure, and each path comprises a first group of BPSK modulation switch circuits, an intermediate-stage four-order low-pass filter circuit and a second group of output switch circuits. The input end of the filter realizes single-end-to-differential connection through the Balun, and the output end of the filter realizes differential-to-single-end output through the Balun. According to the invention, an eight-path time-sharing processing technology of PN code modulation is adopted, strong self-interference suppression is realized by dynamically controlling signal phase inversion, and a differential low-pass filter adopting a capacitance multiplexing technology and a negative impedance design is adopted in an intermediate stage to improve frequency selectivity. Particularly, the switching circuit adopts a three-stage stacking structure to enhance the power processing capability, the clock system adopts an innovative five-tube AND gate design to realize low-jitter PN code modulation, and the output end realizes broadband tuning through the programmable clock system. The method can be widely applied to a full-duplex communication system, and the problems of in-band self-interference and out-of-band interference are effectively solved.

The invention discloses a constellation aggregation frequency offset blind estimation method suitable for a high-speed mobile scene, and the method comprises the steps: carrying out the down-conversion and matched filtering of a received wireless signal for BPSK and MSK modulation signals in a low signal-to-noise ratio and high-dynamic environment, and obtaining a baseband complex signal sequence; aiming at the baseband complex signal sequence in the BPSK modulation form, adopting direct square law transformation to eliminate phase modulation information; an I / Q orthogonal decoupling architecture is adopted for an MSK signal, point-by-point square operation is performed on an in-phase component and an orthogonal component respectively, then subtraction is performed, symbol modulation is eliminated, and then FFT spectrum analysis is performed to estimate Doppler frequency offset. And finally, obtaining a frequency spectrum through windowing FFT transformation, and estimating Doppler frequency offset through peak search. According to the method, the limitation of a traditional pilot frequency method on short sequence precision is broken through, the noise amplification effect of a quadruple spectrum method is effectively overcome, and high-precision and low-complexity carrier frequency offset estimation can still be realized by using a full data segment under a low signal-to-noise ratio.

The invention belongs to the technical field of positioning, and relates to an STM32-based miniaturized low-power-consumption calling beacon machine and a search and rescue system. According to the invention, the hardware combination of the AD9364 chip, the STM32F103 low-power-consumption ARM chip and the FPGA is adopted, and the sleep state control design is matched, so that the electric quantity loss in the standby and invalid communication process of the beacon machine is effectively reduced, and the low-power-consumption operation is realized; the endurance time of the equipment is longer than 48 hours, the 12-hour golden rescue period of maritime search and rescue is fully covered, and the problem that the rescue opportunity is missed due to the fact that a traditional beacon machine is too high in power consumption and not timely in electric quantity supplement is thoroughly solved. By adopting the BPSK modulation mode, a complex modulation-demodulation circuit is not needed, the hardware design difficulty is reduced, and the anti-noise performance, the spectrum utilization rate and the communication stability are remarkably improved; the problem that the signal-to-noise ratio and the spurious-free dynamic range are deteriorated due to the fact that the AD / DA radio frequency front end is affected by clock jitter, power noise and electromagnetic interference is effectively solved.

The application discloses a satellite security communication method based on a QC-LDPC-based McEliece cryptosystem, and belongs to the technical field of information security. The application analyzes QC-LDPC code characteristics for the QC-LDPC code-based McEliece cryptosystem, and constructs a generation matrix G and a check matrix H of the QC-LDPC code based on a random difference group method. Based on the McEliece cryptosystem, a key for satellite security communication is constructed. The satellite security communication method fusing encryption and error correction is used to realize encryption and error correction cascading for plaintext, and to ensure the security and reliability in the communication process. A pseudo-random sequence is generated by using a pseudo-random number generator linear feedback shift register, an error vector is generated according to the pseudo-random sequence and the check matrix, and a sending message is obtained. A modulation signal is generated by using BPSK modulation. After the modulation signal is transmitted through an AWGN channel, a receiving signal for a satellite security communication receiving end is generated. Decryption and decoding are carried out at the receiving end, and satellite security communication of the QC-LDPC-based McEliece cryptosystem is realized.

This invention discloses a method and system for processing transmit and receive data in an MSK spread spectrum system. The spread spectrum sequence d is obtained through a spread spectrum module. n The modulation sequence b is obtained through the BPSK modulation module. n The MSK modulated signal I-channel SigI is obtained through the MSK modulation module. n and Q road SigQ n The MSK signal demodulation module is used to obtain the demodulated D signal. k The despreading module is used to obtain the despreading soft information Ds. m The method and system described above further simplify the MSK spread spectrum system by obtaining the received information bits through the BPSK demodulation module. While ensuring the performance of the MSK spread spectrum system, the implementation complexity of the MSK spread spectrum system transceiver end is reduced by the phase interleaving change law of the IQ path.

A UE is configured for power boosting in the NR network. The processing circuitry of the UE is to encode capability reporting signaling for transmission to a base station. The capability reporting signaling includes a parameter indicating the UE supports power boosting in an uplink transmission when using pi -over- two BPSK modulation or QPSK modulation. The processing circuitry is to decode configuration signaling received from the base station. The configuration signaling is to configure an uplink carrier aggregation band for uplink transmission. The processing circuitry is to decode the configuration signaling to determine the power boosting is enabled for the UE. The processing circuitry encodes uplink data for the uplink transmission using the pi-over-two BPSK modulation or the QPSK modulation with power boosting when the uplink carrier aggregation band includes one uplink component carrier.