A Four-Camera VGA-Resolution Capsule Endoscope System With 80-Mb/s Body Channel Communication Transceiver and Sub-Centimeter Range Capsule Localization

Abstract

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