This paper presents the design of a wideband spiral antenna for ingestible capsule endoscope systems and a comparison between the experimental results in a human phantom and a pig under general anesthesia. As wireless capsule endoscope systems transmit real-time internal biological image data at a high resolution to external receivers and because they operate in the human body, a small wideband antenna is required. To incorporate these properties, a thick-arm spiral structure is applied to the designed antenna. To make practical and efficient use of antennas inside the human body, which is composed of a high dielectric and lossy material, the resonance characteristics and radiation patterns were evaluated through a measurement setup using a liquid human phantom. The total height of the designed antenna is 5 mm and the diameter is 10 mm. The fractional bandwidth of the fabricated antenna is about 21 with a voltage standing-wave ratio of less than 2, and it has an isotropic radiation pattern. These characteristics are suitable for wideband capsule endoscope systems. Moreover, the received power level was measured using the proposed antenna, a circular polarized receiver antenna, and a pig under general anesthesia. Finally, endoscopic capsule images in the stomach and large intestine were captured using an onoff keying transceiver system.
Bibliographical noteFunding Information:
Manuscript received October 4, 2010; revised December 30, 2010; accepted January 27, 2011. Date of publication February 10, 2011; date of current version May 18, 2011. This work was supported by the Korea Ministry of Knowledge Economy through the Intelligent Microsystem Center (IMC). Asterisk indicates corresponding author.
All Science Journal Classification (ASJC) codes
- Biomedical Engineering