Reputation: 1835
I'm trying to directly communicate with the GNSS chip on my device and I am not clear whether the RAW GNSS information is coming directly from the GNSS chip or not. I have used the application provided in the link and it seems to read longitude/latitude information.
Is this information directly coming from the GNSS chip? Further, is the GNSS driver enough to extract this information? Or is longitude/latitude info calculated based on GNSS raw data? If it's the latter, how do I calculate longitude/latitude from raw GNSS (a reference would be sufficient)?
Note: I am not interested in very high accuracy location nor am I interested in indoors location retrieval (using Wi-Fi and Carrier services). I want to record the GPS (or Glonass or whatever) and save it as longitude/latitude format.
Upvotes: 1
Views: 571
Reputation: 1835
Apparently, GPS gives the information. I have found a partial answer here. (this is for GPS, it does not include other GNSS chips like Glonass and Galileo).
Apparently, the GPS hardware outputs results following NMEA format. From the page:
GPS is a commonly used constellation of GNSS satellites. GPS hardware typically reports location information as ASCII strings in the NMEA standard format. Each line of data is a comma-separated list of data values known as a sentence. While each GPS module may choose to report different portions of the NMEA protocol, most devices send one or more of the following sentences:
GPGGA (Fix Information): Includes position fix, altitude, timestamp, and satellite metadata.
GPGLL (Geographic Latitude/Longitude): Includes position fix and timestamp.
GPRMC (Recommended Minimum Navigation): Includes position fix, speed, timestamp, and navigation metadata.
Therefore, GPS driver is sufficient to give longitude/latitude information.
Upvotes: 0