Alright, so before the hysteria starts I'll explain a few things because the stealerships have no idea what's going on either.
Originally, the GPS constellation became fully operational in 1995, at that point it was 80s military technology that was opened to public use on the L1 and L2 bands
Within L1 there is C/A (coarse acquisition) and P-Code (P/Y).
Your phone gps is most likely a L1 C/A chip, as would be your car nav, your quad, etc. Ag GPS that's accurate to a foot or less uses the P(precise)-code.
https://www.trimble.com/gps_tutorial/sub_pseudo.aspx Trimble explains this way better than I can.
These were known as the "Block II" series. ("Block I" were launched in the 70s, at that time top 'dark tech' from the US military and not public)
These are the standard satellite signals all receivers work under.
Now, as GPS's primary purpose is for military use, The technology kept evolving...
The next iteration was known as the Block IIA which was simply a slightly improved system broadcasting on the same frequency, they were then eventually replaced with Block IIR (replenishment) sats as the IIAs hit end of life.
Now, in 2005 - 2009 IIR-M Series satellites were launched. These had a new military frequency, and more notably added the L2C frequency for civilian use... L2C allows for higher precision and much faster signal acquisition times along with some technical differences with the GPS messages themselves.
The next batch of sats was known as the IIF series.
These added the L5 civilian band along with a new military signal. They were also the first set of sats that no longer had option for the US military to degrade the precision of the public signal. This was because L5 is known as the signal for use in "Critical for life human life" applications. It is also used for precision approaches in commercial air planes... It is twice as accurate as L1/L2.
Now, the new set of sats, IIIA and IIIF introduce another new signal, L1C.
The new sats will broadcast L1C on the same frequency as the "legacy" L1 signal, and they are fully backwards compatible This means all current receivers will still work after 2022... And continue to do so.
In order to get the advanced features (high accuracy, better ionosphere correction, etc) you will need new hardware obviously. These sats also broadcast the L5 (critical for life) signal.
L1C without correction should be at least 3x as accurate as current systems (so within a foot instead of a meter)
L1C will begin broadcast when the terrestrial modules are available, which should be 2022. However, L1C will not be FULLY FUNCTIONAL until the entire constellation of sats are launched, which won't happen until the mid 20s
After saying all that, the US plans on transitioning away from the P(Y) signals. While L1 C/A will remain around until at least the 2040s, the P/Y which our farm receivers use is going to get phased out. See the quote from the US Govt below. It is also worthwhile to note that the entire program has had huge delays and keeps getting pushed out. Below is the most up to date information.
So to summarize, the basic signal will be available, but the precision component is going to get phased out eventually.
This is what bucket was referring to in that other thread.
L1C will also be compatible with the European system (GALILEO).
All of the systems out there right now are:
China - BeiDou
Europe - Galileo
Russia - GLONASS
Americas - GPS
India - NAVIC
Japan - QZSS
(Sounds like the UK will start their own system too as with Brexit they'll get kicked out of the Galileo program).
Originally, the GPS constellation became fully operational in 1995, at that point it was 80s military technology that was opened to public use on the L1 and L2 bands
Within L1 there is C/A (coarse acquisition) and P-Code (P/Y).
Your phone gps is most likely a L1 C/A chip, as would be your car nav, your quad, etc. Ag GPS that's accurate to a foot or less uses the P(precise)-code.
https://www.trimble.com/gps_tutorial/sub_pseudo.aspx Trimble explains this way better than I can.
These were known as the "Block II" series. ("Block I" were launched in the 70s, at that time top 'dark tech' from the US military and not public)
These are the standard satellite signals all receivers work under.
Now, as GPS's primary purpose is for military use, The technology kept evolving...
The next iteration was known as the Block IIA which was simply a slightly improved system broadcasting on the same frequency, they were then eventually replaced with Block IIR (replenishment) sats as the IIAs hit end of life.
Now, in 2005 - 2009 IIR-M Series satellites were launched. These had a new military frequency, and more notably added the L2C frequency for civilian use... L2C allows for higher precision and much faster signal acquisition times along with some technical differences with the GPS messages themselves.
The next batch of sats was known as the IIF series.
These added the L5 civilian band along with a new military signal. They were also the first set of sats that no longer had option for the US military to degrade the precision of the public signal. This was because L5 is known as the signal for use in "Critical for life human life" applications. It is also used for precision approaches in commercial air planes... It is twice as accurate as L1/L2.
Now, the new set of sats, IIIA and IIIF introduce another new signal, L1C.
The new sats will broadcast L1C on the same frequency as the "legacy" L1 signal, and they are fully backwards compatible This means all current receivers will still work after 2022... And continue to do so.
In order to get the advanced features (high accuracy, better ionosphere correction, etc) you will need new hardware obviously. These sats also broadcast the L5 (critical for life) signal.
L1C without correction should be at least 3x as accurate as current systems (so within a foot instead of a meter)
L1C will begin broadcast when the terrestrial modules are available, which should be 2022. However, L1C will not be FULLY FUNCTIONAL until the entire constellation of sats are launched, which won't happen until the mid 20s
After saying all that, the US plans on transitioning away from the P(Y) signals. While L1 C/A will remain around until at least the 2040s, the P/Y which our farm receivers use is going to get phased out. See the quote from the US Govt below. It is also worthwhile to note that the entire program has had huge delays and keeps getting pushed out. Below is the most up to date information.
Discontinuation of Codeless and Semi-Codeless GPS Access
The USG commits to maintaining the existing GPS L1 C/A, L1 P(Y), L2C, and L2 P(Y) signal characteristics that enable codeless and semi-codeless GPS access until at least two years after there are 24 operational satellites broadcasting L5. Barring a national security requirement, the USG does not intend to change these signal characteristics before then. Twenty-four satellites broadcasting the L5 signal is estimated to occur in 2024. This will allow for the orderly and systematic transition of users of semi-codeless and codeless receiving equipment to the use of equipment using modernized civil-coded signals. Note that it is expected that 24 operational satellites broadcasting L2C will be available by 2020, with the corresponding ground segment control capability available by 2023, enabling transition to that signal at this earlier date. Civilian users of GPS are encouraged to start their planning for transition now.
The USG commits to maintaining the existing GPS L1 C/A, L1 P(Y), L2C, and L2 P(Y) signal characteristics that enable codeless and semi-codeless GPS access until at least two years after there are 24 operational satellites broadcasting L5. Barring a national security requirement, the USG does not intend to change these signal characteristics before then. Twenty-four satellites broadcasting the L5 signal is estimated to occur in 2024. This will allow for the orderly and systematic transition of users of semi-codeless and codeless receiving equipment to the use of equipment using modernized civil-coded signals. Note that it is expected that 24 operational satellites broadcasting L2C will be available by 2020, with the corresponding ground segment control capability available by 2023, enabling transition to that signal at this earlier date. Civilian users of GPS are encouraged to start their planning for transition now.
So to summarize, the basic signal will be available, but the precision component is going to get phased out eventually.
This is what bucket was referring to in that other thread.
L1C will also be compatible with the European system (GALILEO).
All of the systems out there right now are:
China - BeiDou
Europe - Galileo
Russia - GLONASS
Americas - GPS
India - NAVIC
Japan - QZSS
(Sounds like the UK will start their own system too as with Brexit they'll get kicked out of the Galileo program).
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