# Wide and Dual-Band MIMO Antenna with Omnidirectional and Directional Radiation Patterns for Indoor Access Points

• Yeom, Insu (Graduate School of Nano.IT.Design Fusion, Seoul National University of Science and Technology) ;
• Jung, Young Bae (Department of Electronics and Control Engineering, Hanbat National University) ;
• Jung, Chang Won (Graduate School of Nano.IT.Design Fusion, Seoul National University of Science and Technology)
• Received : 2018.04.30
• Accepted : 2018.10.17
• Published : 2019.01.31
• 60 4

#### Abstract

A wide-band multiple-input multiple-output (MIMO) antenna with dual-band (2.4 and 5 GHz) operation is proposed for premium indoor access points (IAPs). Typically, an omni-directional pattern is used for dipole antennas and a directional radiation pattern is used for patch antennas. In this paper, both antenna types were used to compare their performance with that of the proposed $2{\times}2$ MIMO antenna. We simulated and measured the performance of the MIMO antenna, including the isolation, envelope correlation coefficient (ECC), mean effective gain (MEG) for the IAPs, and the throughput, in order to determine its communication quality. The performance of the antennas was analyzed according to the ECC and MEG. The proposed antenna has sufficient performance and excellent characteristics, making it suitable for IAPs. We analyzed the communication performance of wireless networks using the throughput data of a typical office environment. The network throughput of an 802.11n device was used for the comparison and was conducted according to the antenna type. The results showed that the values of the ECC, MEG, and the throughput have unique characteristics in terms of their directivity, antenna gains, isolation, etc. This paper also discusses the communication performance of various aspects of MIMO in multipath situations.

#### Keywords

Access Point;Antenna Diversity;MIMO;Throughput Data;WLAN

#### Acknowledgement

Supported by : National Research Foundation of Korea

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