Chung-Hao Huang proposes
Kalman-filter drift removal and Heron-bilateration localization
estimation to effectively reduce RSS drift and
localization error, without any sacrifice of localization
granularity and accuracy [19]. Jianwei Niu detects WiFi
APs to form WiFi fingerprints from the signals collected
by ZigBee interfaces, and aligns a pair of fingerprints
with a matching algorithm to improve the localization
accuracy [20], [21].