[Retracted] Low-Power Indoor Positioning Algorithm Based on iBeacon Network

Table 1

Loss of common indoor objects to electromagnetic waves.

Type of obstruction	Corresponding loss (dB)
Cloth	1∼6
Wall	4∼8
Glass window	4∼9
Cement soil	9∼14
Reinforced concrete	15∼24
Gypsum board wall	20∼32
Insulation	22∼39
Metal objects	24∼42