| 摘要 |
A handheld GPS/DGPS receiver/computer apparatus to receive Global Positioning System (GPS) signals having GPS information for determining a GPS-derived location, to receive a differential GPS (DGPS) radiowave signal having differential GPS (DGPS) information for correcting the GPS-derived location, and to display a differentially corrected GPS (DGPS) location. Five embodiments are disclosed. In a first embodiment, a GPS receiver, a DGPS receiver, and a display are built into a handheld apparatus. The GPS receiver is differential-ready to compute the DGPS location. In a second embodiment, a DGPS receiver is built onto a PCMCIA card that inserts into a PCMCIA computer. The PCMCIA computer includes the differential-ready GPS receiver. In a third embodiment, the differential-ready GPS receiver and the DGPS receiver are built onto PCMCIA cards. The PCMCIA computer passes the DGPS information from the DGPS receiver to the differential-ready GPS receiver. In a fourth embodiment, the GPS and DGPS receivers are built onto PCMCIA cards. The PCMCIA computer is differential-ready. In a fifth embodiment, a GPS frequency downconverter and the DGPS receiver are built onto PCMCIA cards. The PCMCIA computer processes the down converted GPS signal and is differential-ready to compute the DGPS location. |
