37results about How to "Increase and rate" patented technology

The invention discloses an interference alignment method based on antenna selection. The sending end antenna selection technology and the sending end antenna selection technology used on a base station side are imported in the interference alignment method disclosed by the invention, and a column vector norm of a channel matrix is used as a selection parameter to select an antenna corresponding to a column vector with a relatively large norm. A pre-encoding matrix is designed according to the channel vector corresponding to the selected antenna, the pre-encoding matrix is composed of two serial matrixes, a front matrix is used for eliminating the interference among different users in the same cell, and a back matrix is designed for the existence of a zero-forcing matrix. Then, the zero-forcing matrix of a receiving end is designed to eliminate the interference caused by a neighbor cell. Firstly, the zero-forcing matrix is designed according to an interference channel matrix to eliminate the interference caused by the neighbor cell; and on the basis, the pre-encoding matrix is designed. In combination with the two technologies, the feedback information amount of the user is reduced, and higher system and rate can be obtained while realizing interference alignment on the premise of not greatly increasing the complexity.

The present invention relates to an ultra-dense millimeter-wave D2D communication interference management method, which mainly solves the shortcomings of the existing methods that the selection of beam width and resource allocation cannot be taken into account in the management of interference at the same time, and provides an ultra-dense ultra-dense technology based on joint beam width selection and resource optimization. The interference management method for dense millimeter-wave D2D communication includes the following steps: first, system modeling and interference management problem modeling are performed on the millimeter-wave D2D communication system; secondly, beamwidth selection is performed by particle swarm optimization to obtain an optimal beamwidth vector; finally Optimum joint power and time slot allocation vectors are obtained by using resource optimization based on convex optimization approximation; the interference management method based on joint beam width selection and resource optimization proposed by the present invention can effectively manage interference, increase the number of parallel transmission links, and obtain more High system and speed.

The invention relates to a mixed PLC / VLC system combined user pairing and subcarrier allocation scheme, belonging to the technical fields of power line communication and optical communication. In the user pairing stage, it is judged whether the number of users is divisible by 4. If yes, the users are divided into four groups in descending order of channel gain, and the first group and the third group, as well as the second group and the fourth group are paired according to the optimal user pairing scheme. ; Otherwise, pair the first user and the last user arranged according to the channel gain, and perform optimal user pairing for the remaining users according to divisible by 4. In the subcarrier allocation stage, each iteration executes the roulette operation, the crossover operation based on the crossover critical value, and the adaptive mutation operation until the convergence condition is met, at which point the subcarrier allocation schemes of all paired user pairs are output. The method of the invention can reduce the computational complexity while ensuring the mixed PLC / VLC system and rate, and can also take into account the fairness and user satisfaction of the mixed PLC / VLC system.

The invention discloses a downlink transmission method for sky-wave massive MIMO communication, which comprises: the sky-wave massive MIMO communication uses a beam-based channel statistical model, which is expressed as the product of a beam matrix and a beam domain channel vector; at the base station side, the beam domain channel is used Statistical information and its sparse characteristics, generate each user’s non-zero beam index set and multi-user non-zero beam index set, obtain the dimension-reduced beam-domain channel, dimension-reduced beam-domain statistical channel information and dimension-reduced beam matrix of each user; On the side, the optimal design or asymptotically optimal design of the user downlink precoding matrix is ​​performed in the dimensionality reduction beam domain, and then the user downlink transmission signal is generated by precoding by using the obtained user downlink precoding matrix. The present invention can significantly improve the spectrum efficiency of sky-wave communication in a high-speed mobile scene, thereby greatly improving the transmission rate and transmission distance, and at the same time solves the problem of complex design of the large-dimensional downlink precoding matrix involved.

The present invention provides a 3D-MIMO downlink multi-user scheduling and adaptive transmission method. The base station adopts a uniform planar antenna array. The method includes the following steps: in the initial state, calculate the horizontal and vertical beamforming index of each user by using statistical channel information; The minimum similarity method is used for multi-user scheduling, and the service user with the smallest similarity is selected to calculate the precoding vector and perform precoding transmission. This method can effectively reduce interference between users, and can obtain higher system throughput with lower computational complexity, can obtain higher sum rate, has high robustness, and is easy to implement; since only statistical information of the channel is required , the amount of channel information required is small, and it is suitable for various typical wireless communication systems; because the influence of channel direct path and correlation matrix is ​​considered at the same time, the channel is more general.

The invention discloses a power allocation method for spectrum sharing by a D2D user pair and a cellular user. The method comprises a first step of initializing iteration times, p<k,n><(0)> and a lagrange multiplier; a second step of calculating an allocation power q<n><(i)> of the cellular user; a third step of performing first-order convex approximation on a data rate R<k> of the D2D user pair and then simplifying according to q<n><(i)>; a fourth step of updating an allocation power p<k,n><(i+1)> and the lagrange multiplier by using a gradient decent method according to a formula obtain after the first-order convex approximation and simplification of p<k,n><(i) and R<k>; and a fifth step of determining whether the lagrange multiplier is converged, if yes, using an allocation power matrix obtained in current calculation as a final allocation power, if not, returning i=i+1 and executing the second step. The method is less complex.