Potential of phase-based ranging as an abscondment sensor for children with autism.

This study addresses the critical unmet need for abscondment detection systems to enhance community access and safety for children with autism. We present the development of a proof-of-concept device that identifies user needs, establishes testing methodologies, and explores the technical challenges in creating a practical solution. Through a structured approach, user requirements and device specifications were established, leading to the creation of a phase-based 2.4 GHz distance-ranging prototype. A series of laboratory-based verification experiments demonstrated significant performance improvements using filtering and alert-triggering mechanisms to mitigate the limitations of phase-based ranging. Although body obstruction remains a challenge, this can potentially be addressed through further co-design with end users. The user-centered design process and experimental framework outlined in this work provide a valuable foundation for researchers seeking to advance abscondment detection technologies for children with autism.