International Journal of Emerging Trends in Engineering and Development Issue 4, Vol.4 (June-July 2014) Available online on http://www.rspublication.com/ijeted/ijeted_index.htm ISSN 2249-6149 R S. Publication (rspublication.com), rspublicationhouse@gmail.com Page 425 DUAL BAND MICROSTRIP FABRIC ANTENNAS FOR MEDICAL APPLICATIONS S. Daya Murali 1 , V. Phani Sasank 1 , O. Manoj Kumar 1 , K. Sravan Kumar 1 and Shaik. Fayaz 1 1 DST-FIST Sponsored ECE Department, KL University, Vaddeswaram, Guntur DT, AP, India Abstract Recent evolution in medical applications is remote health monitoring through antennas. So in this paper we have designed a Microstrip Fabric Antenna used for this application. In this work we have observed how radiation characteristics for health monitoring purpose are varied when different fabrics are used as a substrate for fabric antenna. Here we have used Nylon and Polyester as dielectric materials. This antenna was energised by using coaxial feed. The proposed antenna was designed by using a software HFSS. Keywords: Textile substrate, Wide-Band, Return Loss, Gain. 1. Introduction: The development of wearable technology brought a new evolution in Medical, Military, Telemedicine, Radars and Space applications [2]. In this paper we have designed a flexible, low weight, planar structure, inexpensive, less maintenance Fabric antenna used for medical applications especially for remote health monitoring purpose. Fabric antenna integrates cloth in to the communication system in between doctor and patient. The effect of the user’s body on the antenna characteristics are maximum due to the antenna-body coupling and varies between different antennas separation distance and near-field coupling with tissue [3]. Fabric antenna is a three layered structure which consists of patch, dielectric material as substrate and ground plane [1]. Patch: There are different types of patch are available. But generally for most of the medical applications rectangular patch is used because of ease of fabrication and for easy analysis [1]. Fabrics as Dielectric Material: There are two types of textiles are there conductive and non- conductive textiles. Radiation characteristics and electromagnetic properties differ in between these textiles. Generally for medical applications non-conductive textiles are used. The bandwidth and efficiency greatly depends on the dielectric value and thickness of the textile substrate (dielectric material). Generally fabric materials present a very low relative permittivity that decreases the surface wave loses and improves the impedance bandwidth of the antenna [5]. Here we have chosen Polyester with   = 3.2 and Nylon with   = 4 as a dielectric materials for designing fabric antenna. Textiles are compressible, porous and anisotropic whose thickness and density changes with lowering pressures. The electromagnetic properties of the fabric antennas are varied with the change in temperature and surrounding conditions [5].