Design And Development Of High Isolation Compact Mimo Antennas For Wireless Applications

Abstract

The high data rate and quality becomes a vital role in the current wireless communication devices. In order to satisfy this need the multiple-input and multiple-output (MIMO) technology was introduced. The MIMO means use of multiple antennas at the transmitter and receiver to overcome the effects like scattering, fading and multipath effect during transmission and reception that occurs due to tall buildings, trees, moving vehicles etc. The MIMO also increase the channel capacity without any alteration in the existing infrastructure. The structure of the antenna used in MIMO technology can be designed depending on applications like Bluetooth, Wi-Fi, WLAN, Wi-MAX and ITU bands for handheld devices. However, while designing the compact size multiple antennas the major challenge is to reduce the mutual coupling between them by providing proper isolation. The present work focused on the design of Multi/dual-band MIMO antenna. To reduce the size of wireless devices, the recently developed metamaterial inspired structures, microstrip patch antennas are used to achieve the low profile miniaturized and multi-band antennas. In order to get the multiband and dualband split ring resonator based monopole antenna model is proposed with coplanar waveguide (CPW) feeding, slot loaded microstrip patch for dual-band and asymmetric coplanar strip feeding techniques with split ring resonator for multiband is proposed. The work is extended to 2 × 2 MIMO antennas for mobile applications using dual-band F inverted antennas for mobile and GPS application. Isolation techniques like multiple slot-loading and small profile and open split ring with metamaterial are proposed. The antenna characterization like return loss, gain, radiation pattern, transmission coefficient, envelope cross correlation and channel capacity loss are simulated using an HFFS tool and measured the same using vector network analyzer with the anechoic chamber. Extensive simulations and measured results are verified based on the RLC equivalent circuit models