Design of compact multiple‐input and multiple‐output antenna based on slow‐wave corrugated strips

Abstract

A method of designing two‐element compact multiple‐input and multiple‐output (MIMO) antennas with good isolation based on slow‐wave corrugated strips (CSs) is presented in this paper. Using the slow‐wave characteristic, a pair of CSs is applied as arms of each dipole antenna element to realise the compact design. A metal plane is placed between the two dielectric boards serving as the reflector so that the antenna can achieve good forward radiation. There are two coupling paths between the closely placed antennas: the coupling between the adjacent antenna arms and the coupling with the reflector. By adjusting the phase constants of the two coupling paths, good isolation is achieved in the operating frequency band without any additional de‐coupling structures. A sample of a two‐element MIMO antenna is fabricated at the centre frequency of 5.1 GHz with a bandwidth of 330 MHz. Measured results show good performance to support the design method. As each arm is about 1/8λ0 (λ0 is wavelength in free space), the edge‐to‐edge distance is 0.04λ0, and the isolation in the operating frequency is 15 dB.

A Compact Boat Shaped Dual-Band MIMO Antenna With Enhanced Isolation for 5G/WLAN Application

“…Ultimately, this results in a more inhabited area with less interference. In a MIMO, it is necessary to reduce the space, causing mutual coupling to increase significantly and antenna performance to decrease dynamically [3], [4]. The elements are positioned orthogonally to each other to reduce the mutual coupling, and enhancing the isolation among antenna elements is feasible without using any decoupling structure [5]- [7].…”

Cavity‐backed substrate integrated waveguide MIMO element with enhanced isolation for 5G communication

“…3,4 The corrugated strips of two dipole are placed in parallel by adjusting phase constants of path, leading to reduced mutual coupling. 5 In order to improve isolation, the elements are placed orthogonal to each other. Further, the various isolation improvement approaches are performed for 5G MIMO antenna, including the usage of a defective ground structure (DGS) inserted between elements.…”

“…The spatial diversity techniques were used in MIMO antenna to mitigate mutual interference by keeping enough space between the ports 3,4 . The corrugated strips of two dipole are placed in parallel by adjusting phase constants of path, leading to reduced mutual coupling 5 . In order to improve isolation, the elements are placed orthogonal to each other.…”