Mobile wireless end-systems often experience intermittent loss of connections and/or varying network performance due to their location-dependent data and error rates. These problems can be solved by positioning mobile devices/nodes at the best signal reception locations or areas. Starting from this simple observation, we explore how to exploit such spatially-diverse link-quality by enabling mobile devices to autonomously position themselves to improve their network performance. We first identify research challenges/issues in designing such autonomous mobile wireless end-systems. Then, as a basic building block, we propose a Spatial Measurement and Autonomous Relocation Technique (SMART) that enables end-systems to effectively exploit the spatial diversity in wireless links. Finally, we implement and evaluate a SMART prototype with commodity robots and IEEE 802.11-based wireless cards to demonstrate its feasibility and utility.
We have evaluated our measurement techniques and navigation schemes with a system prototype. The below is one snapshot of spatial measurements of our lab. Also, you can watch our short video clips. More results and a full draft are available upon request.
- Spatial measurement at t = 30 sec
- Spatial measurement at t = 90 sec
- Video Clip 1: Maximizing network coverage from an access point
- Video Clip 2: Following a mobile client to maintain connectivity
- Kang G. Shin
- Kyu-Han Kim
- Dr. Dragos Niculescu at NEC Labs America
- Submitted for publication, 2008
- This project is a collaborative effort between RTCL and NEC Labs America. Some of results reported in this website are based on the progress that Kyu-Han Kim has made as a summer Intern at NEC Labs Amercia during 2007 Summer.