I firmly believe that the GPS we got is the best option we could have picked. I've read a lot of the design papers from the 60s and 70s that formed GPS. The in

I firmly believe that the GPS we got is the best option we could have picked. I've read a lot of the design papers from the 60s and 70s that formed GPS. The initial design was a 3-satellite constellation that would only cover Viet Nam. Options considered [1] included a receiver broadcasting to the satellite (wouldn't scale infinitely) or having an atomic clock in each receiver (high cost and weight). The expectation would be that there were about 100 GPS receivers worldwide: those installed in USAF and USN planes, and possibly some in USN ships or US Army tanks. One constraint they eventually settled on was that a receiver should be portable (less than 50kg) and inexpensive (less than $500k adjusted)[2]. It just goes to show how far we've come from what was at the time considered ambitious in its size and cost goals. [1] https://www.xyht.com/wp-content/uploads/2016/07/3-5-redacted-TOR-10012525-17-1-Briefing-navigation-satellite-study_Redacted.pdf https://www.xyht.com/wp-content/uploads/2016/07/3-5-redacted... page 57 [2] https://www.xyht.com/wp-content/uploads/2016/07/3-5-redacted-TOR-10012525-17-1-Briefing-navigation-satellite-study_Redacted.pdf https://www.xyht.com/wp-content/uploads/2016/07/3-5-redacted... page 73