7 results about "Probability of error" patented technology

The application discloses a kind of underwater acoustic OFDM communication adaptive frequency domain equalization methods using Transform, it is related to underwater acoustic communication technical field, to solve the problems that existing underwater acoustic OFDM equalization method relies on cyclic prefix, is not sensitive to channel dynamic change, hard decision is prone to error propagation, the Transform framework containing only encoder is used in the present application, the soft decision of received symbol is completed by multi-head self-attention mechanism, and adaptive filtering is realized in combination with feedforward network;In the training phase, the loss function is calculated based on the network output and the true value, and the network parameters and the feedforward equalization filter coefficients are updated synchronously;In the inference phase, the network output is fed back to update the filter coefficients, and the real-time changes of the channel are adapted;The present application significantly reduces the probability of error propagation, and improves the communication reliability under complex underwater acoustic channel.

The application discloses a wireless covert detection method and system based on intelligent reflecting surface assistance. The method is as follows: a system model is established, and detection error probabilities of a legal receiver and an illegal detector are derived; an optimal detection threshold is obtained by analyzing an expression of the detection error probability, and the detection error probability is determined; a joint optimization problem of an intelligent reflecting surface phase shift matrix and a transmission power is established; a lower bound of the optimization problem is selected to simplify the optimization problem, and a simplified optimization problem is obtained; the simplified optimization problem is solved, and an optimal intelligent reflecting surface phase shift matrix is determined, and a feasible transmission power is selected to meet a covert constraint requirement. The system comprises a model establishment module, a detection error probability determination module, a joint optimization problem construction module, an optimization problem simplification module and an optimal intelligent reflecting surface phase shift matrix determination module. The application improves the detection performance of the legal receiver, and reduces the detection performance of the illegal detector, so that the requirement of the covert constraint is met.

The application discloses a decision fusion method and system in a multi-listening scenario in covert communication and belongs to the technical field of wireless communication. The method comprises the following steps: configuring a limited total block length for each listening node, and dividing the total block length into a detection block length and a transmission block length; each listening node performs local signal sensing, generates a local decision result by using the detection block length, and sends the local decision result to a fusion center by using the transmission block length; the fusion center allocates an optimal fusion weight for each decision result based on the local detection performance and the transmission performance of each listening node according to the criterion of minimizing the global detection error probability; the fusion center calculates a weighted sum based on the fusion weight and the corresponding decision result, compares the weighted sum with an optimal decision threshold of the fusion center, and makes a global decision on whether the target signal exists. The application realizes the optimal performance of a whole link from sensing to fusion, and improves the reliability and accuracy of signal detection.

The present disclosure relates to a 5th generation (5G) or pre-5G communication system for supporting a higher data transmission rate than a 4th generation (4G) communication system such as long-term evolution (LTE). Disclosed is a method performed by a terminal that may comprise: receiving configuration information for a CSI report from a base station; acquiring a channel quality indicator (CQI) table on the basis of the configuration information for the CSI report; and transmitting CSI including a CQI according to the CQI table to the base station, wherein the CQI table is configured on the basis of a first CQI table of a case where transport block error probability is 0.1 and a second CQI table for a case where transport block error probability is 0.00001. The method performed by the terminal may further comprise: receiving configuration information relating to a physical uplink shared channel (PUSCH) or a physical downlink shared channel (PDSCH) from the base station; identifying a modulation and coding scheme (MCS) table on the basis of the configuration information relating to the PUSCH or PDSCH; and acquiring a transport block size (TBS) on the basis of the MCS table, wherein the MCS table is configured on the basis of a first MCS table configured by default and a second MCS table configured for low spectral efficiency (SE) in the base station.

A kind of simultaneous transmitting and reflecting reconfigurable intelligent surface (STAR-RIS) network friendly interference assisted information transmission method is composed of steps of constructing transmission signal model, establishing channel model, deducing average minimum detection error probability, analyzing transmission interruption probability and hidden throughput, determining secret interruption probability. The present application adopts the reflection and transmission dual functions of STAR-RIS, combined with the construction of transmission architecture for non-orthogonal multiple access of friendly interference technology, and proposes a friendly interference assisted information transmission method. The method constructs independent transmission channels for hidden users and secure users through STAR-RIS, and cooperates with the friendly interference mechanism to improve the detection error probability of the monitor, effectively avoiding the communication process from being identified. By determining the secret interruption probability, the risk of intercepting information by the eavesdropper is reduced, and the confidentiality of data is ensured. At the same time, with the help of power allocation strategy, the channel differences of multiple users are balanced, the transmission interruption probability is controlled within the preset threshold, and the transmission stability and hidden throughput are significantly improved. The present application has the advantages of reasonable transmission design, easy implementation, excellent concealment performance, good security effect, reliable transmission and high throughput, and can be used in the field of wireless communication technology.

This invention discloses a method and system for polar code confidence propagation bit-flipping decoding in UAV communication, relating to the field of polar code technology. The method includes the following steps: performing confidence propagation decoding on the communication signal received by the UAV and encoded in polar codes to obtain an initial decoding sequence; if the initial decoding sequence fails cyclic redundancy check (CRC), a bit-flipping set construction process based on particle swarm optimization (PSO) guided by a fixed error probability PE is used. The optimal combination of all information bit error probabilities is searched in the solution space using the PSO algorithm to construct a bit-flipping set E, and confidence propagation decoding and CRC are performed again; the sequence that passes CRC is output as the final decoding result to the UAV's flight control system or mission system for UAV communication control. This invention forms a closed loop of "search-flip-verify," ensuring the effectiveness of the flipping operation, avoiding new errors introduced by erroneous flips, and guaranteeing the real-time performance and accuracy of UAV actions.