Dead reckoning module combines the inertial navigation system and altitude barometer module information. This system completes the output of standard NMEA-0183 protocol, the realization of the true sense of inertial navigation and positioning. 结合DeadReckoning模块的递推导航和气压计模块的海拔高度信息,能够完整的输出标准的NMEA-0183语句,真正意义上的实现惯性导航定位。