Capsule endoscope system design with body channel communication transceiver

Abstract

This desertion is for introducing low-power, energy efficient Body Channel Communication (BCC) transceiver IC design and its integration in capsule endoscope application. In decade, increasing requirements of convenient and higher energy efficiency near human body gives more attention to BCC technology. BCC, utilizing human body as communication medium, can take advantage of both wireline and wireless communication in body area. Many of research has actively investigated from the principle to practical transceiver design. However, Current BCC research have limitation in two aspect : 1) Research progress are not summarized carefully due to lack of precise technical review

2) Most of design has a limitation since they cannot expand hardware to designated system. Each of the key contribution of the desertion is introduced in chapter 2, and chapter 3, 4.

First several underlying key considerations of BCC would be introduced from its fundamental basis to target applications. Paper will starts from the comparison with general RF technology and BCC, and introduce historical review of BCC researches. Two analogical perspective to understand BCC and several challenges in its design will be discussed. After that, with following recent transceiver IC design trends, design efforts and their achievements would be covered.

In later part, a small form-factor, light weight wireless capsule endoscope (WCE) system with body channel communication (BCC) transceiver ICs is revealed. The proposed system allows VGA resolution image transferring and capsule localization. The transceiver ICs are composed of capsule chip and receiver chip, implemented in 65nm CMOS process. In the capsule side, the proposed system provides 360-degree image capturing through 4-camera integration to reduce miss rate. Also, a dual-band pulse shaping BCC transmitter is proposed to enable low-power (<1mW), high-speed (80Mb/s) image transmission. In the receiver side, contact attenuation compensated-received signal strength indicator (CAC-RSSI) is proposed to increase capsule localization accuracy. The external system is composed of 8 receiver nodes that allows signal demodulation and localization of the capsule. To reduce transceiver payload and system power consumption, image encoder is implemented in capsule. The transceiver IC is integrated in capsule system and verified with body mimicking phantom. The proposed system satisfies compatibility with medical grade diagnosis by operating longer than 8 hours with 4 frame per second (fps) and 12 hours with 2 fps with conventional two silver oxide, 55mAh coin battery. The tested localization accuracy shows less than sub-cm range.