Progress In Electromagnetics Research C, Vol. 116, 249–264, 2021 Reconfigurable Antenna Design for Internet of Medical Things Farha Usman 1, * , Mohammad G. Siddiqui 2 , Prakhar Yadav 1 , Sweta Singh 1 , and Ram S. Yadav 1 Abstract—This proposal presents a novel design of a reconfigurable antenna with frequency, polarization, and pattern diversities for wireless body area networks. The design makes use of a 3.2 mm thick FR4 substrate of 39 × 36 mm 2 dimensions with a square patch and partial ground structure. The antenna operates in sixteen different modes and resonates at various frequencies ranging from 2.456 to 14.384 GHz. The proposed model has the capability to exhibit elliptical as well as linear polarization with different radiation patterns. For suitability of the proposed design in healthcare applications its SAR analysis has been performed along with other antenna characteristics like reflection coefficient, gain, radiation pattern, and axial ratio. Four PIN diodes have been used to switch the antenna operational modes. 1. INTRODUCTION Modern telecommunication systems have emerged with the requirement of multiple antenna standards. Various applications require an altogether different set of operating frequencies, polarization, and pattern. Employing different antennas for different requirements is not that feasible, which demanded for a single antenna capable of catering to all requirements. This has laid the foundation of cognitive and reconfigurable antennas which are reconfigured or rebuilt to cater the desired operating characteristics and specifications [1]. The reconfiguration is accomplished by a thoughtful alteration of antenna’s effective aperture [2]. For the purpose, switches (electrical, optical or thermal), actuators (motors or linear actuators), or material change (plasmonics or liquid crystals) can be used. The reconfigurability can be classified as frequency, polarization, radiation pattern, and hybrid [3]. Modern antennas face the limitation of low fractional bandwidth (typically 7%). Such antennas are not compatible with nowadays wireless communication systems [4]. In addition, recent developments in wireless communications urge the necessity of multiband antennas [5]. Mostly antennas exhibit elliptical polarization; a few antennas show linear polarization; and some offer circular polarization characteristics. Linear polarization is desired in C-band and Ku-band applications whereas circular polarization is highly required in satellite communications [6]. In [7], authors have proposed a frequency reconfigurable antenna with slots that resonated at frequencies 2.3304 GHz, 2.2425 GHz, and 2.054 GHz as per the slots orientation in counterclockwise direction at 0 ◦ , -45 ◦ , and -90 ◦ , respectively. In [8], a band reconfigurable antenna has been investigated that offered a wideband and four narrow band modes of operation. A pentagon slot resonator frequency reconfigurable antenna has been reported with wideband operational characteristics in [9]. Wireless applications require a multiband antenna as it offers the features of multiple antennas of different resonant frequencies [10]. A multiband frequency reconfigurable antenna has been investigated in [11] which switched between quad band and dual band modes with the PIN diode’s OFF and ON states, respectively. Authors of [12] have proposed a frequency and polarization reconfigurable antenna Received 13 September 2021, Accepted 27 November 2021, Scheduled 7 December 2021 * Corresponding author: Farha Usman (usmanfarha@gmail.com). 1 Department of Electronics and Communication, University of Allahabad, Prayagraj, India. 2 Department of Electronics, Banasthali Vidyapeeth, Rajasthan, India.