This paper studies the problems of H∞ performance analysis and controller design for NCSs with multiple sensors and actuators, where communication channels are shared by multiple sensors and actuators. The proposed periodic time sequencing scheme for controller may introduce less conservatism than the common controller gain based method. Based on the structure decomposition of free-weighting matrix, sufficient conditions guaranteeing the H∞ performance of the considered system are presented, then a new switched controller design method is proposed to optimize H∞ performance of NCSs. The merit of the proposed H ∞ performance analysis lies in its less conservatism, which is achieved by adopting periodic time sequencing scheme for controller and imposing no any constraint on the structure of free-weighting matrix. The simulation results illustrate the merits and effectiveness of the proposed switched controller design.