Ecived 2nd generation real time location time is with VLF technique. We utilize VLF technology which can provide grid positioning resolution. Through advanced digital signal processing technology, we redefined the VLF technique whose anti-interference performance is improved one order than before. The new technique is already used in mobile devices for miner positioning system in China and is used in metro vehicle monitoring system for train arriving and leaving detection in Shanghai, China as mentioned above. With the new VLF technique, patented algorithm, and reconstructed system, Ecived VLF RTLS system is highly cost effective. One single system permits hundreds of tags to be tracked in all directions, covering a maximum area of 700 m2 to 1200 m2. Our VLF RTLS tag can be easily embedded into other electron devices and systems to provide location information. Because of unique system construction and location algorithm, users can get their location information in local instead of from remote service. This feature avoids the user location is gathered by remote service which may cause privacy and security issues and is a key important different from RF RTLS system in market. Because VLF has good penetrating ability, the Ecived VLF RTLS system can avoid the usual locating problems of other RF RTLS systems caused by obstacles and multipath effects. This technology has also reduced significantly the requirements of line of sight which had troubled users before.