Evaluation of a TDMA-based energy efficient MAC protocol for multiple capsule networks

Wireless capsule endoscopy is a new kind of medical device, which monitors the gastrointestinal tract of the human body. It can be envisaged that in the future more than one capsule could be ingested by the patient and they operate collaboratively in the gastrointestinal (GI) tract to perform certain diagnostic and therapeutic tasks. These mobile capsules and the coordinator node, which is attached to the abdomen of the patient, form a wireless network. The capsule devices are typically powered by batteries, therefore, energy efficient medium access control (MAC) protocols for multiple capsule networks are necessary. This article proposes a novel energy efficient MAC protocol for multiple capsule networks based on time division multiple access (TDMA). An asymmetric up/down link network architecture is introduced. A novel TDMA slot assignment scheme is proposed and simulation results using Qualnet show that the proposed MAC protocol achieves lower energy consumption than B-MAC and star topology TDMA.