A Dual Band Planar Inverted F Antenna for Body- Centric Wireless Communications Mohammad Monirujjaman Khan, Musa Magani, Atiqur Rahman and Clive Parini School of Electronic Engineering and Computer Science, Queen Mary University of London Mile End Road, London E1 4NS {mohammad.khan; musa.magani; atiqur.rahman}@eecs.qmul.ac.uk Abstract—In this paper, a dual band planar inverted F antenna (PIFA) is proposed intended to be applied in various applications in healthcare and sport monitoring. The antenna is dual band at 2.45 GHz (ISM band) to communicate with other co-located body-worn devices scattered on the body or body worn base station and 1.9 GHz (PCS) band to communicate from on-body device to off-body units/access point or other wider e-health networks. The free space and on-body measured and simulated performances of the proposed antenna are shown and analyzed. The antenna shows very good on-body radiation efficiency as 58.03 % for 1.9 GHz and 52.0 % for 2.45 GHz. The dual band PIFA also shows good on-body gain as 3.74 dBi and 3.08 dBi at 1.9 GHz and 2.45 GHz respectively. I. INTRODUCTION With the rapid development of biosensors and wireless communication devices bring new opportunities for Body-Centric Wireless Networks (BCWN) which have recently received increasing attentions due to their promising applications in medical sensor systems and personal entertainment technologies [1-5]. Body-centric wireless communications (BCWCs) is a central point in the development of fourth generation mobile communications. In common healthcare monitoring scenarios, it is very important for the antenna to communicate with on-body devices located on the body and also establish the communications with the off-body devices. Antennas are the essential component for wearable devices in body-centric wireless networks and they play a vital role in optimizing the radio system performance. When the antenna is placed in or close to a human body (lossy medium), the performances change to that of free space operation. For body-centric antennas, the presence of the human body in the proximity of the radiating structure reduces the radiation efficiency and gain. This is due to electromagnetic absorption in body tissues, which results in frequency detuning, radiation pattern distortion and variation of antenna impedance. Recently, there has been increasing interest in research and development for designing wearable antennas; however, at this point there have been no significant breakthroughs in the design of wearable antennas [6-13]. Peter Hall et al. has done extensive study on narrowband antenna (2.45 GHz) for on-body communication [6-7]. In [8] a dual band button antenna for WLAN (2.45 GHz, 5.2 GHz) applications was presented by John Batchelor. Akram et al. presented various wearable antennas in the 2.4 GHz (ISM band) for on-body communications in [9-11]. In addition, stacked patch antenna with switchable propagating mode for UHF body-centric communications at 2.45 GHz has been proposed in [12]. In [13], Scanlon et al. presented a set of higher mode microstrip patch antennas operating at 2.45 GHz for over the body surface communications. In this paper a dual band planar inverted F antenna (PIFA) is proposed for on-body and off-body communications intended to be applied in various applications in healthcare and sport performance monitoring. On-body and free space performances of the dual band PIFA are investigated in simulation and experimentally as well. The rest of the paper is organized as follows; section II illustrates the antenna design, section III presents result and analysis, and finally section IV draws the main conclusion. II. ANTENNA DESIGN Figure 1 shows the schematic design and fabricated version of the proposed dual band planar inverted F antenna. The antenna was modelled on FR4 substrate with a thickness of 1.57 mm and a relative permittivity of 4.6. There is a full ground plane at the back of the substrate of the antenna. The overall ground plane size of the antenna is 63×34 mm and the total height is 6.92