GPS always cannot work when test train goes into a tunnel, we will lose test location information while the network test still goes on. In this situation, if there is a call drop event, we will not know where the accident happens. It will cause problems to network optimization.
Pinpoint is a available tool in Airlync test equipment to help to define position; it can help to simulate real-time position information of test train. The tool was marked in the left picture, it can be found in Map page of Airlync.
Before a test train goes into a tunnel, we need to mark a moving trace just along the railway to tell the tool where the train will go. Just like the simulant points which were selected on the left map by Pinpoint tool.
When trains move into a tunnel, GPS fails to work, the tool will dot on our moving trace to tell where the train is. The moving curve shows in the right picture, it will help us to know an estimated location.
Speed of the train is another important factor to simulate a real-time position information, Pinpoint tool dots in a fixed time interval, only after knows the speed, the tool will dot a more accurate point on the map to report the real-time position.
Just as the above figure shows, open “Map Configuration”, select a average speed of the train after click the “Pinpoint” option.
Before the GPS becomes invalid, a real-time speed always shows on the test screen. The speed will help to setup this parameter.
Any network problems happened in tunnel area, we just play back the test log. For example a call drop event there, stop playing the log firstly, then check the map, you will know where the problem is, just as picture shows.
When GPS invalid, the Pinpoint tool can simulate it to define position information. Pinpoint is a helpful tool to use in tunnel.