基于wifi的室内定位算法

室内定位算法，有助于研究者认清研究方向，给定位算法一个准确的描述，是很好的参考教材。the possibility for the user to be notified by visible and Waveformof Distance
audible warnings using buzzer and led
ar to
Very close to al
1903
Tme「 samples
Fig 4 Distance measurement using the RSSi signal
The system is used to determine the distance between
Fig. 2. Tag4M Data Acquisition System
tags and 2, 3, 4 or more APs. The tag scans after the aps
ⅣV. EXPERIMENTS
and sends the rssi values for each ap to the ap which is
associated
The system presented above can be used for objects or In order to read the corresponding rSsi values of all
people localization in an indoor enviro
found access points, a""operation is implemented at
Let's suppose a building where several objects are Tag4M level. The time to scan is smaller than few
distributed all over
milliseconds, because the tag doesnt associate with the all
For a better understanding of the system, it is showed an APs. These values are sent to a pC where the localization
experiment where the objects are placed only at one floor. algorithm is implemented in LabVIFW20 10 (see Fig. 5)
Each of these objects has attached a tag. The devices are
Table I presents a scan operation result. In this case
used to determine the location of the objects in the four APs(which are placed in the floor building)named
building and the distance between tags and APs. To Hawk, Helicopter, Tag4M and WitagServer are detected
measure the distance, the RSSI is processed. This method The corresponding rSSi values(in dBm) measured by the
is not very accurate and is strong depended to the Tag4M are reported for every AP
environment, but is very easy to implement with the
TABLE 1. A SEQUENCE OF RESULTS FOR THE SCANOPERATION
The Fig 3 presents the experiment environment for one EXFCUTED ON THE TAG4M DEVICE
oor where the colored circles represents the APs and the
rectangles represents the objects intended to be located
This floor is divided in six rooms separated by walls