GPS function (Global Positioning System) is informs the position of UR5i v2, LR77 v2, Bivias v2 and SmartFlex routers. GPS receiver is a part of VF module in both routers. GPS receiver receives signal from American satellite system NAVSTAR GPS. The receiver calculates the accurate position from this information, all over the world (latitude, longitude, altitude, speed of movement, direction of movement and accurate time). VF module can receive all information at the same time, it means receiving GPS signals and transmitting and receiving UMTS/LTE data. The connector for GPS antenna is placed on the front panel of routers in the middle of the antennas for UMTS/LTE signals. See picture below.
Function of GPS is implemented in routers UR5i v2, LR77 v2, Bivias v2 and SmartFlex. Note that it is always the full version of routers (UR5i v2, LR77 v2). GPS receiver communicates by protocol NMEA 0183. We have to use software the module of GPS, for the correct functioning of GPS. Details about software modules can be found here. The software module is processes information from GPS receiver and distributes the information in different ways.
1. Via Web interface – configuration of GPS module
Program module has own configuration web page. Basic information about position, parameters, date and movement speed of the router are visible here. On the same page is a link to Google Maps (Show on map). After click on this link you will be redirected to the map with the real position of the router.
2. Via output of NMEA protocol
to the expansion ports (PORT1, PORT2 and USB). These options are possible to set on the web configuration page. Data is sent from the router to the selected ports (PORT1, PORT2, USB) in format NME0183. For connection with remote server is used protocol SNMP TRAP. The user sets address of the router and time period for timed transfering of SNMP TRAP. This solution is highly suitable for re-storing data to the database of the remote server. The second advantage is that the router may not be available from the remote computer and function may be as a client on the Internet.
GPS receiver in practice
Passengers uses are using routers to connect to the internet on public vehicles. The router can share information about accurate position and movement of vehicles. Information about real time from the GPS module can be used for other routers in the site. For sharing can be used NTP server which is implemented in each router. NTP server can be used for sharing accurate time.
|Antenna||50Ω – active, passive|
|Protocols||NMEA 0183 v3.0|
|Acquisition time||Hot start: 1sWarm start: 29sCold start: 32s|
|Accuracy||Horizontal: lower then 2m (50%); lower then 5m (90%)Horizontal: lower then 2m (50%); lower then 5m (90%)Horizontal: lower then 2m (50%); lower then 5m (90%)|