Printed collinear two‐antenna element for WLAN access points in a MIMO system

A printed collinear two-antenna element suitable for application in a wireless local area network (WLAN) access point in a multi-input multi-output (MIMO) system is presented. The printed element comprises one dipole antenna and one monopole antenna, both printed in a collinear configuration on a narrow FR4 substrate of width 12 mm and length 120 mm and showing good omnidirectional radiation characteristics. It has been found that an antenna system formed by using two proposed elements spaced 75 mm or larger can have good isolation (better than −20 dB) between any two of the four antennas in the two proposed elements. With the comparison to the conventional antenna system formed by four discrete antennas, the antenna system with two proposed elements shows a much smaller lateral length. This characteristic makes the proposed collinear two-antenna element advantageous for application in a MIMO system. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 930–933, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21522