Abstract: The present invention discloses a modulation method and a modulation apparatus applicable to an OvXDM system, and an OvXDM system. On the one hand, an initial envelope waveform is virtually cut off, and a modulation-domain shift interval is calculated by using a virtual cutoff width of the initial envelope waveform, such that a symbol width obtained after modulation becomes smaller, and a transmission rate is improved; on the other hand, because the initial envelope waveform is virtually cut off but not really cut off, shifting and superimposition are still performed on an initial envelope waveform with tailing, such that the waveform still retains a good performance, such as a relatively narrow width and relatively fast side lobe attenuation, in a corresponding domain. Therefore, in the present invention, the good performance of the waveform is retained in the corresponding domain while the transmission rate is increased.

Abstract: An overlapped multiplexing-based modulation and demodulation method and device are disclosed. In the modulation method, a precoding structure is used, and a transmit end first performs parity check product code-based coding on an input information sequence, generates a factor graph for a coding result and according to a coding rule, then performs overlapped multiplexing-based modulation and coding, and transmits a coded signal by using an antenna. In the demodulation method, a signal is transmitted by using a channel, and after receiving the signal by using an antenna, a receive end first performs digital signal processing, including processes such as synchronization and equalization, then performs overlapped multiplexing-based demodulation and decoding, and finally performs factor graph-based belief propagation decoding on a decoding result, to finally obtain a decoded sequence.

Abstract: The present invention discloses a decoding method and a device applied to an OvXDM system, and an OvXDM system. An access node in a Trellis diagram corresponding to the OvXDM system is selected in a decoding process. A superior path is selected by improving a method for calculating an accumulated branch measurement and with reference to a weighting factor. In addition, a node with a smallest accumulated branch measurement is extended, and a best decoding path is selected. When the present invention is applied to a decoding process of an OvXDM system in which a quantity of times of overlapped multiplexing or a quantity of coding branches is relatively large, design complexity and a calculation amount of the OvXDM system are reduced, so that the OvXDM system has a relatively low bit error rate, and performance is improved.

Abstract: In an overlapped multiplexing-based decoding method and device, and modulation and demodulation method and system provided in this application, a convolution operation with a header and without a tail is split into group operations with both a header and a tail by using a slide group decoding scheme and based on association between adjacent symbols in an OvXDM system, and then each group of sequences is decoded by using a corresponding decoding algorithm.

Abstract: The present application discloses a forward and backward smooth decoding method and device suitable for an OvXDM system, and a system. Importance weights of particles in a particle set corresponding to a symbol are calculated by using a forward process and a backward process, and screening is performed with reference to forward importance weights of particles and backward importance weights of particles, to output a final decoding sequence.

Abstract: The present application discloses a signal sampling and recovery method and apparatus applicable to an OvXDM system, and the OvXDM system. The method includes: constructing, based on design parameters, an observation matrix ? that is irrelevant to an original signal y, wherein the observation matrix ? is a two-dimensional M*S matrix, S is a length of the original signal y, and M is smaller than S; compressing the original signal y based on a formula Ycs=?Y, to obtain a M*1 compressed signal Ycs, wherein Y is a S*1 column vector that is obtained according to the original signal y; and reconstructing the compressed signal Ycs based on a predetermined algorithm, so as to recover the original signal y. The present application implements accurate recovery of the original signal at a reduced sampling rate, thereby reducing hardware requirements of the system and improving feasibility of the technical solution.

Abstract: This application discloses a fast decoding method and device suitable for an OvXDM system, and an OvXDM system. According to this method, there is no need to traverse all state nodes and expanded paths of the state nodes in a decoding process, and only some state nodes and paths are selected through measure sorting for expansion. Therefore, the decoding complexity can be greatly reduced and decoding efficiency is improved. The decoding complexity does not increase drastically as a number K of times of overlapped multiplexing increases, as in a conventional decoding solution. This resolves the problem that the spectral efficiency conflicts with the decoding complexity and the decoding efficiency.

Abstract: This application discloses a soft value extraction method and device applicable to an OvXDM system, and the OvXDM system. In the method, waveform coding is performed on all symbols in a hard value sequence, to generate a predictive value after overlapped coding; the symbols in the hard value sequence are reversed one by one, and overlapped coding is performed on each reversed symbol and associated symbols before and after the reversed symbol, to generate a predictive value of the reversed symbol; and for each symbol in the hard value sequence, a soft value of the current symbol is calculated based on A×(+1??1), where A is a coefficient related to a channel type, +1=?yrx?y+1?, and ?1=?yrx?y?1?2; if y+1 is a predictive value of the symbol obtained after overlapped coding and before reversing, y?1 is a predictive value of the symbol obtained after overlapped coding and reversing; and yrx is a received signal sequence.

Abstract: This application discloses a decoding method for an OvXDM system, including: generating an augmented matrix B related to a received symbol information sequence; performing singular decomposition on the augmented matrix B; and performing decoding by using a total least square method, to obtain a decoded output information sequence. This application further discloses an OvXDM system. In a specific implementation of this application, decoding is performed by using the total least square method.

Abstract: The present invention provides a signal modulation method. The method includes: generating a transmit signal pulse waveform, where a width of the pulse waveform is ?, each pulse waveform is associated with n symbols (n>1), a width of each symbol is ??, and ?? = ? n ; performing an operation on every n consecutive symbols in a to-be-sent symbol flow and the pulse waveform according to a preset operation manner, to generate an associated signal of the symbols and the pulse waveform; and sending the associated signal by using a transmission channel. The present invention helps improve spectral efficiency of a system. In addition, symbols are mutually constrained based on a correlation between the symbols, and information symbols are scattered to a plurality of symbols, thereby helping improve a capability of resisting noise and attenuation by a signal.

Abstract: The disclosure relates to an overlapped multiplexing modulation method, apparatus, and system.

Abstract: A method includes: receiving a to-be-decoded symbol sequence, where the to-be-decoded symbol sequence includes N symbols; dividing the received to-be-decoded symbol sequence into a first symbol sequence and a second symbol sequence; calculating first distances between the first symbol sequence and each of corresponding 2K ideal superimposed symbol sequences, and obtaining paths corresponding to relatively small distances based on the first distances; sequentially performing sequence detection on each symbol in the second symbol sequence based on the paths corresponding to the 2k-1 relatively small distances, calculating second distances between each symbol in the second symbol sequence and each ideal symbol sequence, and after the sequence detection is performed on a last symbol, obtaining an ideal symbol sequence corresponding to a minimum distance based on the second distances; and using the ideal symbol sequence corresponding to the minimum distance as an output symbol sequence.

Abstract: A method for generating a library of expression vectors comprising a plurality of donor sequences and a plurality of oligo-linker nucleic acids, termed Oligonucleotide Linker-Mediated DNA Assembly (OLMA), is described. Also described are applications of the OLMA method, including the simultaneous tuning of several factors in metabolic and biological pathways, and the combinatorial high throughput optimization of metabolic and biological pathways.