Abstract: Techniques for tracking a location of an item retainer are described. In an example, a computer system may receive one or more signals from one or more devices. At least one device may be located at a distance from a radio frequency identification (RFID) reader. The RFID reader may be located at a space opening and may cover a read zone around the space opening. The signal(s) may indicate that a condition to activate the RFID reader is met. This condition may be associated with a state of the space opening or a proximity of an item retainer to the read zone. The computer system may activate the RFID reader based on the condition being met and may determine a progress of the item retainer through the space opening based on whether an RFID tag was read by the RFID reader while the RFID reader was activated.

Abstract: Features are disclosed for a wearable scanning device that can passively initiate scanning for wireless identifiers such as RFID tags. The wearable scanning device may include a force sensor, an accelerometer, or a motion activated switch that can initiate the scanning when detecting an action performed by an associate (e.g., lifting) without an express intent from the associate to scan.

Abstract: Features are disclosed for collecting wireless identifier signals such as from RFID tags to accurately determine the location of items associated with the wireless identifier. Carefully coordinating when to begin and end collection of the signals and analysis of the signals and signal characteristics (e.g., received signal strength) allow a carried item to be identified and its location determined. Additional features are described to further validate the location of the item.