3 results about "Mimo channel matrix" patented technology

The invention relates to a power line communication transmission method, device and system, and the method comprises the steps: firstly obtaining an MIMO channel matrix of a target subcarrier in a power line communication system, then determining a quality evaluation parameter of the target subcarrier according to the channel matrix of the target subcarrier, and then determining a mode matching threshold according to the quality evaluation parameter and the mode matching threshold. And determining a diversity multiplexing mode of the target subcarrier, and finally controlling a sending end to carry out subcarrier mapping and signal transmission processing on the target subcarrier according to the diversity multiplexing mode of the target subcarrier. Namely, by dynamically evaluating the subcarrier quality and adjusting the diversity multiplexing mode in real time, the problem that the prior art cannot adapt to the rapid change of the power line channel is solved, and the method has the advantage of improving the transmission reliability and the rate adaptability of the power line communication system in the dynamic channel environment.

The invention relates to a laminated intelligent metasurface-assisted low-altitude holographic MIMO channel optimization fitting method, and belongs to the technical field of digital communication. The method comprises the following steps: initializing system parameters, and determining beam forming matrixes of TX-SIM and RX-SIM; constructing a spatial correlation matrix of a transmitting and receiving end, and determining a spatial correlation holographic MIMO channel matrix, a singular value matrix and a scaling factor of an end-to-end channel; calculating channel fitting errors corresponding to a plurality of groups of preset super-atom phase shift configurations; and by taking minimization of a channel fitting error as an optimization target, carrying out iterative optimization on the super-atom phase shift by adopting a linear decline particle swarm optimization method, and obtaining and outputting optimal phase shift configuration. According to the method, the optimization problem caused by multilayer coupling and non-convex constraint of the laminated intelligent metasurface in a low-altitude dynamic environment is effectively solved, the global optimization capability is enhanced, the channel fitting error is reduced, and the channel capacity and the communication quality of a holographic MIMO system are improved.

This invention relates to a MIMO channel estimation method based on a diffusion model and expectation propagation under low-resolution quantized observations. It involves acquiring a quantized observation matrix, a pilot matrix, and historical channel data. A denoising diffusion implicit model is employed, and the prior distribution of the MIMO channel matrix is ​​learned unsupervised through forward noise addition to obtain the channel prior score function. To address the nonlinear constraints introduced by the quantized observation matrix, a posterior distribution satisfying the quantization interval constraints is constructed, and the expectation propagation algorithm is used to iteratively approximate it as a Gaussian distribution, calculating the likelihood gradient. Combined with the prior score function, the likelihood gradient is integrated into the inverse sampling process of the denoising diffusion implicit model. Using the quantized observation matrix and pilot matrix as guiding conditions, the initial noise is gradually sampled to a channel estimation result consistent with the quantized observations through gradient guidance. Compared with existing technologies, this invention has advantages such as high accuracy, strong versatility, and good stability.