A method and system for enabling more robust detection, positioning and time solution using GPS satellite ranging signals based on a simultaneous, all-in-view coherent PRN code signal processing scheme rather than acquisition of GPS signals one at a time. Additionally, a plurality of signal processing operating modes are provided that include a Factory Start mode, a Hot Start mode, a Subsequent Fix mode and a Reacquisition mode. Each mode provides a user receiver with an ability to quickly determine its current probable location without undue delay when a prior probable location has been obtained. Preventing undue delay of predicting a probable location of the user can be especially valuable in conditions where weak signals are being received, or in high interference environments, or when signal jamming conditions are being experienced, or when a combination of such environments is present.