Harbin Engineering University

About: Harbin Engineering University is a education organization based out in Harbin, Heilongjiang, China. It is known for research contribution in the topics: Control theory & Computer science. The organization has 31149 authors who have published 27940 publications receiving 276787 citations. The organization is also known as: HEU.

Dual-Band Metasurface-Based Decoupling Method for Two Closely Packed Dual-Band Antennas

Abstract: In this communication, a metasurface-based decoupling method (MDM) is proposed to reduce the mutual couplings at two independent bands of two coupled multiple-input-multiple-output (MIMO) antennas. The metasurface superstrate is composed of pairs of non-uniform cut wires with two different lengths. It is compact in size and effective in decoupling two nearby dual-band patch antennas that are strongly coupled in the H-plane with the edge-to-edge spacing of only 0.008 wavelength at low-frequency band (LB). The antenna is fabricated and measured and the results show that the isolation between two dual-band antennas can be improved to more than 25 dB at both 2.5–2.7 GHz and 3.4–3.6 GHz bands, while their reflection coefficients remain to be below −10 dB after the metasurface superstrate is introduced. Moreover, the total efficiency is improved by about 15% in the low band and the envelope correlation coefficient (ECC) between the two antennas is reduced from 0.46 to 0.08 at 2.6 GHz and 0.08 to 0.01 at 3.5 GHz. The proposed method can find plenty of applications in dual-band MIMO and 5G communication systems.

Dynamic Output-Feedback Dissipative Control for T–S Fuzzy Systems With Time-Varying Input Delay and Output Constraints

Abstract: This paper develops a new fuzzy dynamic output-feedback control scheme for Takagi–Sugeno (T–S) fuzzy systems with time-varying input delay and output constraints based on $(Q,S,R)$ - $\alpha$ -dissipativity. The proposed controller, called a $(Q,S,R)$ - $\alpha$ -dissipative output-feedback fuzzy controller, takes into consideration the abstract energy, storage function, and supply rate for the disturbance attenuation and provides a unified framework that can incorporate existing results for $\mathcal {H}_{\infty }$ and passivity controllers as special cases for T–S fuzzy systems with time-varying input delay and output constraints. A dynamic parallel distributed compensator is used to design the $(Q,S,R)$ - $\alpha$ -dissipative output-feedback fuzzy controller to ensure the asymptotic stability and strict $(Q,S,R)$ - $\alpha$ -dissipativity of closed-loop systems described by a T–S fuzzy model that satisfies some output constraints. By employing the reciprocally convex approach, a new set of delay-dependent conditions for the desired controller is formulated in terms of the linear matrix inequality. The effectiveness and the applicability of the proposed design techniques are validated by an example of control for active suspension systems for different road conditions.