14results about How to "Improve bit error rate performance" patented technology

The invention discloses an underwater CSK-OFDM modulation and detection method based on LED linear constraint, and the method comprises the steps: enabling a transmitter to map a data bit stream of a constellation diagram into a complex symbol stream, converting the complex symbol stream into a real number time domain sequence through an ACO-OFDM module, carrying out the LED amplitude limiting of the time domain sequence, and obtaining a time domain clipping sequence; transmitting the time domain clipping sequence in a UOWC channel through a corresponding LED, introducing symbol timing deviation and amplitude limiting noise into a frequency domain by a receiver, and processing the time domain clipping sequence by using an ACO-OFDM module again to obtain a received signal; under the maximum expectation framework, the probability from each alternative constellation diagram is calculated, symbol timing deviation and additive white Gaussian noise variance are estimated, a globally optimal solution is obtained, and a constellation diagram recognition result is output through maximum likelihood demodulation. According to the method, the linear range constraint of the LED and the complex environment under the UOWC scene are comprehensively considered.

The invention belongs to the technical field of wireless communication, and particularly relates to a multi-user symbiotic wireless communication channel estimation and signal detection method. According to the designed transmission frame structure, the main system sending symbol is recovered by estimating the combined channel containing the reflection device sending symbol, and then the multiplicative relationship between the main system sending symbol and the reflection device sending symbol is decoupled, so that the error rate performance of main system transmission and reflection device transmission is improved. The scheme provided by the invention is simple to implement and has very high application value.

The application discloses a high-parallelism storage-computation integrated polar code decoding method based on coset decoding, and belongs to the technical field of channel coding and decoding. The method comprises the following steps: constructing an error pattern group and a check constraint subgroup; performing coset division on the error pattern group to obtain a set of mutually disjoint cosets; screening a limited number of minimum cosets based on the minimum Hamming weight of the cosets; and performing parallel decoding processing on the paths corresponding to the minimum cosets in the storage-computation integrated architecture. k The number of paths in the traditional multi-bit decoding is reduced from 2 to a preset number L through coset division, and the parallel execution of the likelihood information updating and the path metric calculation is realized in combination with the calculation-type storage array, so that the decoding performance is ensured, the calculation complexity and the hardware resource consumption are significantly reduced, and the decoding throughput and the energy efficiency are improved.

The invention discloses a parallel stepped convolutional code space coupling coding and decoding (PSCBCC) method and device, belongs to the technical field of channel coding, and is suitable for a large-bandwidth communication scene. According to the method, a frame of data is divided into multiple groups of sub-data, parallel convolutional coding of three paths of input of current sub-data, interleaved previous sub-data and an interleaved previous check sequence is realized by utilizing a parallel coding unit, a current check sequence is generated, and the sub-data and the check sequence are respectively reserved to different subsequent moments to form asymmetric coupling; and during decoding, a parallel decoding unit is matched with a coding structure, and a plurality of groups of log-likelihood ratios are input to realize iterative updating. The throughput rate is improved through parallel processing, the bit error rate performance is enhanced through asymmetric coupling, multi-code-rate adaptation is supported, and the performance is superior to that of existing BCC and 4G / 5G standard codes.

This invention discloses a signal detection method for an OTFS system based on an adaptive wavelet scattering convolutional neural network, comprising: converting the data symbols to be transmitted to the DD domain, and then obtaining an OTFS signal through an OTFS modulator; the OTFS signal reaching the receiver through a wireless channel; at the receiver, transforming the received signal back to the DD domain using an OTFS demodulator; extracting the real and imaginary signal matrices from the received OTFS signal, performing a three-layer wavelet scattering network transformation on these two matrices to obtain scattering feature coefficients for each layer, concatenating the scattering feature coefficients along the feature channel direction to reconstruct a high-dimensional feature matrix of the signal, and using it as the input to an adaptive wavelet convolutional neural network 2D-AWCNN to obtain the possible values ​​corresponding to each QAM symbol; and performing 16-QAM demodulation on the output of the adaptive wavelet convolutional neural network 2D-AWCNN using a demodulator to obtain the output bits used for signal detection.

This invention discloses a fast pattern-coupled sparse Bayesian multi-user detection method, comprising the following steps: Step S1: Construct a large-scale IoT uplink system model, convert the multi-timeslot signal measurement model into a single measurement vector model, and assign a pattern-coupled Gaussian prior distribution to the sparse signal to be detected, initializing the hyperparameter set; Step S2: Based on variational inference, derive the relaxed evidence lower bound of the system's logarithmic marginal likelihood function; Step S3: Update the hyperparameter set using the variational expectation maximization method to maximize the relaxed evidence lower bound; Step S4: Determine whether the iteration termination condition is met. If it is, stop the iteration and output the recovered active user signal; otherwise, return to step S3. This invention effectively utilizes the adjacency correlation of each user's transmitted signal through a pattern coupling mechanism, significantly improving detection accuracy; and it can meet the requirements of real-time performance and high reliability in large-scale IoT scenarios.

The invention discloses a stepped convolutional code (HSCBCC) coding and decoding method and device for high-speed large-bandwidth data transmission, and belongs to the technical field of communication channel coding. According to the coding method, a frame of data is divided into a plurality of groups of sub-data, a convolutional code coder is adopted to code a combined sequence of current sub-data and previous specific sub-data and a previous specific check sequence subjected to interleaving processing, and a current check sequence is generated; respectively retaining the current sub-data and the verification sequence to different subsequent moments as input; the decoding method comprises the following steps: iteratively processing channel information and extrinsic information of the corresponding sub-data and the check sequence, and outputting a decoding result. According to the invention, an asymmetric double-coupling structure is adopted, the bit error rate performance is superior to that of an existing space coupling coding scheme under the same resource consumption, and the method is adaptive to a multi-code-rate scene and is suitable for the technical field of large-bandwidth wireless communication or optical fiber communication.

The application provides a LoRa modulation method based on three-dimensional constellation assistance, and belongs to the field of signal processing. By dividing the information bit stream into a frequency index bit stream and a constellation mapping bit stream, and respectively using them to generate a three-dimensional orthogonal LoRa base signal and perform three-dimensional constellation mapping, a new three-dimensional signal space is constructed for joint modulation. This core design enables more information bits to be transmitted simultaneously within a symbol period, significantly improving the data rate of the system. More importantly, compared with the traditional two-dimensional constellation, the three-dimensional constellation can provide a larger minimum Euclidean distance between symbols under the same modulation order. This fundamental improvement in geometric characteristics directly translates into stronger anti-interference capability and lower bit error rate of the signal in noise and fading channels. Therefore, the method effectively improves the spectral efficiency of the LoRa system while enhancing its transmission reliability, achieving a synergistic improvement in performance.

The invention discloses a channel code pattern optimization method based on Gaussian weighted hybrid approximate density evolution, and relates to the technical field of wireless communication. The method includes constructing a modulation system. A delay module is introduced at a sending end, joint information source and channel decoding is carried out at a receiving end, and likelihood information of delay bits is fed back to a demodulator. Likelihood information probability distribution output by all sub-channels of the system is obtained, and it is confirmed that the distribution does not meet symmetric Gaussian distribution. Based on the characteristics of likelihood information output by each sub-channel under the condition of a single constellation point, decoding convergence performance is analyzed by adopting a density evolutionary algorithm of Gaussian weighted hybrid approximation, and Gaussian weighted hybrid approximation distribution of the likelihood information output by each sub-channel is obtained. And searching and optimizing by using a density evolutionary algorithm based on Gaussian weighted hybrid approximation as an analysis tool to obtain an optimized channel code basis matrix. And constructing a channel encoder by using the optimized channel code basis matrix to replace the original channel code so as to improve the bit error rate performance of the system in the waterfall region.

This application discloses a detection and decoding method and related equipment based on SCMA, relating to the field of communication technology. The SCMA-based detection and decoding method includes: receiving symbol sequence data corresponding to multiple users; iteratively decoding and detecting the symbol sequence data using a preset expectation propagation algorithm and a soft-output decoder; and outputting bit sequence information after reaching a preset stopping condition. The symbol sequence data includes multiple variable nodes and multiple functional nodes, which are iteratively updated based on prior information. This application reduces the bit error rate during data transmission.

The invention relates to the technical field of channel coding and decoding, and discloses a coding and decoding method and device for high-speed large-bandwidth data transmission. According to the coding method, a data frame is divided into multiple groups of sub-data, each group of sub-data and a plurality of adjacent groups of sub-data are merged and interleaved and then coded to generate a check sequence, and a code word containing the sub-data and the check sequence is output; according to the decoding method, iterative decoding is carried out on code words generated by encoding, related log-likelihood ratios are input, updating information is output through a convolutional code decoder, and a preset iteration sequence is adopted until decoding is completed. According to the invention, the coding structure is simplified, the hardware implementation complexity is reduced, the excellent bit error rate performance is maintained, the adaptability is high, and the method is suitable for a large-bandwidth communication scene.

This invention relates to a physical layer network coding coordination scheduling method for linear multi-hop underwater acoustic networks. This method introduces PNC (Physical Number Coordination) technology into the link access strategy design of linear multi-hop underwater acoustic networks, overcoming the inherent inter-hop interference limitations of such networks. The method includes the following steps: all sensor nodes transmit local data packets in time slot 1; all sensor nodes except the upstream and downstream nodes simultaneously receive data packets from upstream and downstream neighbor nodes in even-numbered time slots, obtaining coded data packets after PNC mapping; the downstream sensor node receives data packets from upstream neighbor nodes in even-numbered time slots; all sensor nodes transmit data packets received in the previous time slot in odd-numbered time slots; and the sink node completes data packet reception in even-numbered time slots. Compared with existing technologies, this invention exhibits better performance in channel utilization, throughput, and end-to-end latency, especially in channel utilization, which can reach half of the theoretical upper limit.

This invention discloses a multipath-resistant LoRa communication method combining block interleaving and matched filtering, belonging to the field of Internet of Things (IoT) technology. The steps are as follows: Block interleaving reduces the amplitude of strong multipath signals by dividing the signal into equal blocks and then swapping the order of these blocks, followed by deinterleaving at the receiver; matched filtering increases the signal-to-noise ratio (SNR). Matched filtering is selected based on amplitude criteria, first filtering the preamble symbol, then performing circular correlation operations using the preamble and data symbols. This method effectively resists multipath interference and improves the bit error rate performance of LoRa communication. It is low in complexity, low in power consumption, and simple to implement, making it suitable for multipath-intensive indoor and outdoor communication scenarios and shallow water acoustic communication.

The invention discloses a unitary space-time modulation and demodulation method and device, electronic equipment and a storage medium, and the method comprises the steps: carrying out the unitary space-time modulation of target data based on a unitary space-time modulation signal constellation set, and obtaining a unitary space-time modulation signal; a first signal in the modulation signal constellation set is generated based on a Hadamard matrix; and converting the unitary space-time modulation signal into an offset quadrature phase shift keying signal, and converting the offset quadrature phase shift keying signal into a continuous phase modulation signal. According to the unitary space-time modulation and demodulation method and device, the electronic equipment and the storage medium, the USTM constellation set head signal is constructed based on the orthogonal characteristic of the Hadamard matrix, the complete constellation set is generated through diagonal matrix design, finally, signal phase continuity is achieved through constant envelope processing, and the peak-to-average ratio can be remarkably reduced.