Smart tags are devices that can be used to detect the location of objects that they are attached to. They are mostly used to locate keys, and bags The smart tags communicate with the user's phone via Bluetooth or Z-waves. Smart tags are primarily used to detect the location of the objects that they are attached to. With a little change in design, I believe they can be made into more sensitive versions that can serve a purpose similar to the proposed blanket. A security alarm mode can be added to the functions of the tags so that it goes off when someone tampers with the object it is attached to.
A challenge with such a device is its short range . If the device is used in a smart home then the signal from the device can be relayed between other devices via Z-waves and the range problem is solved. For longer distances, it will not be practical to use such devices since their small sizes limit their range. One of the advantages of smart tags is that they can be attached to almost any object to set up an alarm system. They are also small and inconspicuous so they can be placed at spots that a trespasser will least expect.