Abstract: Disclosed is a method of tracking a user's location. The method comprising: receiving coordinate of each of adjacent mobile devices therefrom, estimating a channel environment to select an optimal channel model, calculating distance between the user's mobile device and each of the adjacent mobile devices based on the selected channel model and calculating coordinates corresponding to a current position of the user's mobile device based on the calculated distance.

Abstract: Disclosed is a method of tracking a user's location. The method comprising: receiving coordinate of each of adjacent mobile devices therefrom, estimating a channel environment to select an optimal channel model, calculating distance between the user's mobile device and each of the adjacent mobile devices based on the selected channel model and calculating coordinates corresponding to a current position of the user's mobile device based on the calculated distance.

Abstract: Disclosed herein is a built-in RFID tire tag. The built-in RFID tire tag includes an antenna and a circuit unit. The antenna is mounted in a tire, and is configured to be operated by resonating with radio waves, which are transmitted from an RFID reader and to have a repetitive corrugated shape. The circuit unit is configured to be operated by being supplied with power using the radio waves. The antenna includes a pair of tag radiators. Each of the tag radiators is divided into a first region and a second region. The corrugation density of the second regions, which are close to the circuit unit, is greater than that of the first regions, which are not close to the circuit unit. The first regions, which depend on rotational motion of the tire, adapt flexibly to bending and torsion of the tire by the difference between the corrugation densities.

Abstract: Disclosed herein is a built-in RFID tire tag. The built-in RFID tire tag includes an antenna and a circuit unit. The antenna is mounted in a tire, and is configured to be operated by resonating with radio waves, which are transmitted from an RFID reader and to have a repetitive corrugated shape. The circuit unit is configured to be operated by being supplied with power using the radio waves. The antenna includes a pair of tag radiators. Each of the tag radiators is divided into a first region and a second region. The corrugation density of the second regions, which are close to the circuit unit, is greater than that of the first regions, which are not close to the circuit unit. The first regions, which depend on rotational motion of the tire, adapt flexibly to bending and torsion of the tire by the difference between the corrugation densities.