Directional Wireless Search for Lost Mobile Devices

The search process is divided into two distinct phases: a first search in a broad predetermined range, and a second search in a narrower range. This segmentation allows the system to efficiently cover large areas initially, then focus resources on smaller areas where targets are more likely to be found, reducing overall search time while maintaining comprehensive coverage.

The search range is dynamically adjusted based on received responses. After performing the first broad search and receiving responses, the system determines directions of external apparatuses and subsequently performs a second search only in narrower ranges toward those specific directions. This dynamic adaptation optimizes search efficiency by concentrating efforts on promising areas.

The system implements feedback mechanisms where external apparatuses respond to search signals by transmitting response signals back to the communication apparatus. These responses provide information about the direction and presence of external devices, enabling the system to reliably locate portable devices even when they are moved or lost, without compromising their wireless portability.

The communication apparatus performs preliminary searches in broad ranges before narrowing down to specific directions. By proactively searching and receiving responses in advance, the system establishes reliable location information that guides subsequent more focused searches, ensuring that portable devices can be located even when users move them to different locations.