International Journal of Research and Review Vol.7; Issue: 10; October 2020 Website: www.ijrrjournal.com Research Paper E-ISSN: 2349-9788; P-ISSN: 2454-2237 International Journal of Research and Review (ijrrjournal.com) 369 Vol.7; Issue: 10; October 2020 Ultra-Wideband MIMO Antenna with Band-Notch Characteristics at WLAN Band Chandrasekhar Rao Jetti 1 , P. Chanukya 2 , R. Anand 3 , Sk. Mothi Sulthana 4 , Sk. Faziya Sultana 5 1 Associate Professor, Bapatla Engineering College, Bapatla, A.P., India 2,3,4,5 UG Students, Bapatla Engineering College, Bapatla, A.P., India Corresponding Author: Chandrasekhar Rao Jetti ABSTRACT In this paper, MIMO antenna exhibiting band- notch characteristics at WLAN band for Ultra- wide band applications. The proposed UWB MIMO antenna comprises of pair of identical elements fed by microstrip line feed. Three slots are etched on the ground to achieve good impedance matching properties from 3.5 to 12.6 GHz. A rectangular stub is protruded from the ground plane to enhance the isolation more than 15dB between the antenna ports. An inverted C- shaped slot is incorporated on each element to create band-notch at WLAN band from 5 to 5.6 GHz. The results show that the proposed antenna is well fit for UW applications. Keywords: MIMO antenna, Ultra-wideband, Isolation, Band-notch, WLAN band. 1. INTRODUCTION The present and future wireless communication systems demand for high data rate, more channel capacity, quality of service and coexistence with existed systems. Ultra-wideband technology is a promising solution because it offers higher datarates at lower emission powers, wide bandwidth, low cost and coexistence with other systems. However, UWB technology suffers from multipath fading in indoor applications. Multiple input multiple output is prominent technology to avoid multipath fading problem in UWB system. [1-3] But the MIMO systems suffer from low isolation between the antenna ports which effects the whole system performance. Several isolation enhancement methods were developed to increase the isolation. [4-8] Methods include the use of tree-like structure on the ground plane, [4] etching a T-shaped slot and a line slot on the ground, [5] protruding ground structure, [6] adopting wideband neutralization line, [7] and using a protruded ground branch structure. [8] Since, UWB is operating from 3.1 to 10.6 GHz, there are chances to receive the frequency interference from WLAN (wireless local area network) band (5.15- 5.825 GHZ). So, to mitigate the frequency interference, UWB MIMO antenna with band-notch characteristics is needed. Many techniques were proposed in the early time to reduce the interference from WLAN includes inserting λ/4 and λ/2 slot resonators on the ground plane, [9] An inverted U-slot resonator is placed on the feed line, [10] inserting open stub in the printed folded monopole, [11] microstrip lines loaded with trident-shaped strips, [12] quarter-wave stub connected to the ground. [13] In this communication, ultra-wideband MIMO antenna with band-notch feature at WLAN band is presented. The following sections discuss the antenna design, results and discussion and then conclusions. 2. Antenna Design The proposed antenna of size 26 31 0.8 mm 3 is designed on a FR-4 dielectric substrate with ε r of 4.3 and loss tangent of 0.0027 as shown in Figure 1. The proposed antenna elements are similar to that of the antenna presented by Mchbal A