BLE	Bluetooth low-energy
PbS	position-based service
RFM	reference fingerprinting map
RSSI	received signal strength indication
PDR	pedestrian dead reckoning
GNSS	global navigation satellite system
APs	access points
RF	radio frequency
LSE	least square estimation
kNN	k-nearest neighbor
IMUs	inertial measurement units
ZVU	zero-velocity update
RM	radio map
SLAM	simultaneous localization and mapping
EKF	extended Kalman filter
CDFs	cumulative distribution functions