Antenna Design for Impulse-Radio-Based Wireless Capsule Endoscope Communication Systems

Impulse radio (IR) is a form of signal with ultrawide bandwidth spread spectrum suitable for short-range communications. In this paper, a triband on-body coil antenna for IR-based wireless capsule endoscope (WCE) communication system signal reception is proposed and experimentally verified. The proposed antenna contains three frequency bands (operating frequency: 38.5, 48.2, and 57.6 MHz) in 10-60 MHz band. For antenna transmission performance evaluation, three corresponding single-band in-body transmitting antennas are designed. Reflection and transmission coefficient, electric and magnetic field distributions, and specific absorption rate are simulated with a muscle equivalent phantom. In addition, transmission performance is measured in a liquid phantom by a battery powered IR transceiver. Measured results show that 50 mm attenuation is 32, 43, and 52 dB at 38.5, 48.2, and 57.6 MHz, respectively. It can be expected to realize a total data rate of 3.75 and 2.5 Mbps less than 50 and 90 mm, indicating that the proposed antenna can be used for WCE image reception.