Hello,
I admit, it’s not very clear. But I thinks my knowledge in GPS are too limited to fully understand.
Il found this old (2011) EGNOS user guide (sorry, it’s in French):
Chapter 10 Evolution, they said (sory, google translate, I was lazy to translate myself
):
“In addition, EGNOS is fully interoperable with the GPS system which has currently entered a modernization phase. In fact, GPS will emit new civil signals on the L5 frequency band, thereby improving system performance. In addition, the European Galileo satellite navigation program should be operational from 2014 for the IOC (Initial Operations Capability) phase including a constellation of 18 satellites in total. This will be followed by the FOC phase (Full Operations Capability) which will see the complete Galileo constellation (27 satellites + 3 spares). A certain number of studies are underway to analyze the possible evolutions of EGNOS, in particular to take into account counts the corrections and the integrity: • of the GPS signals transmitted on L5, • of the signals transmitted by the Galileo system.”
On the Europeen Global Navigation Satellite Systems Agency website (they are in charge of EGNOS and Galileo), they said:
https://egnos-user-support.essp-sas.eu/new_egnos_ops/egnos-system/about-egnos
“EGNOS augments the GPS L1 (1575.42 MHz) Coarse/ Acquisition (C/A) civilian signal by providing corrections and integrity information for GPS space vehicles (ephemeris, clock errors) and most importantly, information to estimate the ionosphere delays affecting the user .”
Also in the EGNOS Open Service (OS)Service Definition Document, in the introduction, we found the same information:
“Presently, EGNOS augments GPS using the L1 (1575.42 MHz) Coarse/Acquisition (C/A) civilian signal function by providing correction data and integrity information for improving positioning, navigation and timing services over Europe.”.
But nothing on the L2 band.
So I thinks you are right since the beginning: EGOS provide a correction only for L1 GPS band C/A signal.
But when I look on the GPS Signal plan (GPS Signal Plan - Navipedia), C/A signal are transmited only on L1 band.
But which is not very clear to me is: why a L1/L2 receiver couldn’t use L1 C/A signal with EGNOS augmentation and in the same time the signals from L2 Band ? I thinks it’s this is where my knowledge in GPS too limited
.
I have to had the Novatel Introduction to GNSS (An Introduction to GNSS Book | NovAtel) book on the list of all the thinks I should read but I haven’t the time
.
Math