Indoor Positioning Kalid Azad Advisor: Prof. Littman (MAE dept) Co-advisor: Prof. Cook Cs398 Project Proposal

Old Checkpoint expectations By checkpoint (~1 month) Thoroughly examined existing technology Created algorithm Ordered hardware Begin coding software Deliverables Report Detailed description of algorithm Hardware Requirements Portion of software implementing algorithm

Current Status Submitted report to Prof. Littman Description of algorithm Original algorithm changed (see future slides) but described in report Hardware requirements Have laptop and wireless card (thank you Prof. Wang!) More access points the better Software Have begun coding software to track and record signal strength, find averages, etc.

Difficulties, Surprises, etc. Lots of changes! Original approach: Using phase shift of radio waves Problems: Indoor radio propagation complex, need to make custom hardware & software (take months to learn to build, debug, test). Better as a year-long project. Solution: Use existing wireless technology (802.11) Saves time, get down to coding/testing right away New approach: create “radio map” of signal strength profiles, match current signal to closest profile Use directional antenna for accuracy Prelim. Results on next slide, due to changes

Preliminary Results Logging signal strengths Can detect variations from moving laptop, introducing obstacles Determine that new approach better than old Better documented, existing drivers & utilities, hardware already exists However, still learned a lot Studied numerous existing technologies (GPS, IR, ultrasonic, radio), read many research papers First approach theoretically possible, difficult in practice Learned tradeoffs made in real world, under limited time/resources

Future steps Try to get additional hardware Build directional antenna, gather data Write up results & what I’ve learned Hopefully, at least room-level accuracy (at best ~1 meter accuracy?) Write about why certain approaches are used, why they are better Write about other applications Have spoken extensively with Brent Waters (grad student) about security applications Proving your location to others Alternative to IR ‘Active Badge’ ?