Where can I find the GPS/GLONASS RF path?

Question

satellite navigation

I want to receive and process signals from satellite navigation systems on my own. There are a huge number of GPS / GLONASS receivers on sale, but most of them immediately give out ready-made coordinates. They have the following disadvantages:

• low coordinate update rate (usually 1 Hz, although I have met modules up to 10 Hz).
  
• the data is output using the NMEA protocol. (a very inconvenient protocol, it requires a lot of resources for parsing and clogs the channel with uninformative data).
  
• the built-in filter does not always work correctly (teleportation to the nth number of meters is possible), and does not have the ability to set its own filtering parameters.
  

The best module I've come across, Geos3M, is free from some of these shortcomings, but I want more.
I want to calculate the coordinates myself according to the received signal data. The ATR0601 chip with a very inconvenient interface came under attention, but maybe someone knows the best solutions.

Answer 1

If ATR0601 seems to you "with a complex interface", then the rest will definitely not seem easier to you, its interface is quite typical and there is nothing superfluous in it.
It is not clear why you liked Geos - it is almost no different from many other receivers.
If you want to do the processing yourself, you can use the uBlox receivers, which provide "raw" measurement data (pseudorange and phase) in a fairly well-documented binary protocol with an update rate of up to 10Hz. This is enough for independent processing (which is done, for example, by the RTKlib toolkit).
Your requirements for a "separate RF path" and "the ability to set your own filtering parameters" contradict each other. The filtering of throws according to the Kalman algorithm is applied in receivers already to ready-made coordinates.