Inventory tracking

A building comprising:

• an inventory system comprising:
• a first inventory system unit;
• and
• a second inventory system unit,
• wherein the first inventory system unit comprises at least a configuration transmitter configured to generate a configuration field inside a first field zone to configure one or more Ultra High Frequency (UHF) radio-frequency identification (RFID) tags within the first field zone into a configured state deviating from a default state, and
• wherein the second inventory system unit comprises at least an interrogation transceiver configured to generate an interrogation field inside a second field zone that is at least partly outside the first field zone to subsequently interrogate a set of one or more UHF RFID tags that are both:
• within the second field zone, and
• in the configured state;
• and
• a wall enclosing an interior, the wall having a gate providing access to an exterior,
• wherein the first field zone is at least partly within the interior,
• wherein the second field zone is at least partly in the exterior or in a corridor giving access to the exterior, and
• wherein a path from the interior to the exterior via the gate extends through both the first field zone and the second field zone.

A building comprising:

• a first room,
• a second room,
• a wall between the first room and the second room with a gate for allowing access between the rooms, and
• an inventory system comprising:
• a first inventory system unit;
• and
• a second inventory system unit,
• wherein the first inventory system unit comprises at least a configuration transmitter configured to generate a configuration field inside a first field zone to configure one or more Ultra High Frequency (UHF) radio-frequency identification (RFID) tags within the first field zone into a configured state deviating from a default state, and
• wherein the second inventory system unit comprises at least an interrogation transceiver configured to generate an interrogation field inside a second field zone that is at least partly outside the first field zone to subsequently interrogate a set of one or more UHF RFID tags that are both:
• within the second field zone, and
• in the configured state;
• wherein the first field zone is at least partly within the first room,
• wherein the second field zone is at least partly within the second room, and
• wherein a path from the first room to the second room via the gate extends through both the first and the second field zone.