This paper presents novel cascaded channel estimation techniques for an intelligent reflecting surface-aided multiple-input multiple-output system. Motivated by the channel angular sparsity at higher frequency bands, the channel estimation problem is formulated as a sparse vector recovery problem with an inherent Kronecker structure. We solve the problem using the sparse Bayesian learning framework which leads to a non-convex optimization problem. We offer two solution techniques to the problem based on alternating minimization and singular value decomposition. Our simulation results illustrate the superior performance of our methods in terms of accuracy and run time compared with the existing works.@en

In this work, we focus on partitioning dynamic graphs with two types of nodes (bi-colored), though not necessarily bipartite graphs. They commonly appear in communication network applications, e.g., one color being base stations, the other users, and the dynamic process being the varying connection status between base stations and moving users. We introduce a partition cost function that incorporates the coloring of the graph and propose solutions based on the generalized eigenvalue problem (GEVP) for the static two-way partition problem. The static multi-way partition problem is then handled by a heuristic based on the two-way partition problem. Regarding the adaptive partition, an eigenvector update-based method is proposed. Numerical experiments demonstrate the performance of the devised approaches.@en