Self-diagnosis Page Terminology

Self-diagnosis Page Terminology



Network Section:

- MQTT: This stands for Message Queuing Telemetry Transport. It's a network protocol often used in the Internet of Things (IoT) for device-to-device communication. It works on top of TCP/IP and is designed for situations where a small code footprint is required and network bandwidth is limited.
 
- 0 ms: This represents the latency or response time for the MQTT protocol, with "0 ms" indicating no measurable delay, which is exceptionally good.

-APP: Strong: This indicates the strength of the application's connection to the network, with "Strong" signifying a robust connection. 

RTK Section:

- Mode: This usually refers to whether the RTK (Real-Time Kinematic) positioning is enabled or disabled. RTK is a satellite navigation technique used to enhance the precision of position data derived from satellite-based positioning systems (like GPS, GLONASS, Galileo, or BeiDou).

- L2: This refers to the L2 carrier frequency used by GPS satellites, which carries the P(Y) code and the L2C code used for precision positioning. L2 is at 1227.60 MHz and is one of several frequencies used by satellite navigation systems.
 
- Signal Levels: Besides L2, there are several other carrier frequencies such as L1, L5, etc. Each serves different purposes, such as:
      - L1: At 1575.42 MHz, it carries both the precision (P) and the coarse/acquisition (C/A) codes.
      - L3: This frequency (1381.05 MHz) was originally designed for nuclear detonation detection as part of the United States Nuclear Detonation (NUDET) Detection System Payload (NDS) to comply with arms control treaties. The L3 signal carries the payload for the system that detects and transmits information about nuclear detonations back to the ground for analysis. 
      - L4: The L4 band is at 1379.913 MHz and is being studied for additional ionospheric correction. As of my last update, it was not yet in widespread use. The potential uses for L4 include additional corrections for ionospheric errors, aiding in the robustness of the GPS signal against interference, and possibly providing a secondary civil signal.
      - L5: At 1176.45 MHz, this frequency is intended for safety-of-life applications and offers improved ionospheric correction.

- Status: 
  In the context of the RTK GPS signal status, the numerical values typically correspond to a predefined scale set by the device manufacturer to indicate the quality or strength of the RTK GPS signal. Here's what the numbers could generally indicate:
        Status 1: This might represent "No Fix", meaning the GPS receiver has not found enough satellites to determine its position.
        Status 2: This often indicates a "2D Fix", which means the receiver has enough satellites to determine a position but not altitude, so it has latitude and longitude but not elevation.
        Status 4: This signifies a "Strong" or "Fixed" signal, where the receiver has a strong connection with enough satellites to accurately determine the 3D position (latitude, longitude, and altitude).
        Status 5: For RTK GPS systems, it means that the system is in a "Float RTK" mode, where it has a solution with floating ambiguity as opposed to a "Fixed RTK" mode, which has fixed ambiguity and       therefore more precise measurements.

- Heading: This refers to the orientation of the device in terms of travel direction.

- Satellite: The number of satellites that the system is currently receiving signals from, which in this case is "21". More satellites typically mean better positioning accuracy.

- Base GNGGA / Rover GNGGA: These are strings in NMEA format that contain GPS fix data from the base and rover, respectively. GNGGA is a common type of NMEA data that includes information such as time, latitude, longitude, fix quality, number of satellites, and horizontal dilution of precision (HDOP).
The GNGGA string can be broken down as follows:

- Latitude and Longitude: The location data, following the format of degrees, minutes, and decimal minutes.

- Fix Quality Indicator: the GNGGA sentence specifically provides essential fix data, which is information about the position of a GPS receiver. The parameter you provided indicates a good status for both Yarbo and RTK station. Here is a full  list of what each number stands for:
      0: Invalid fix. The receiver does not have a fix on the satellites, so the data is not reliable.
      1: GPS fix (SPS). A standard positioning service fix that indicates a valid fix and that the receiver is receiving signals from the GPS satellites.
      2: Differential GPS fix, which is a more accurate fix that uses a nearby reference station.
      3: PPS fix, used mostly by the military.
      4: Real Time Kinematic (RTK). A high-precision fix that uses a fixed base station and a moving receiver.
      5: Float RTK. Similar to RTK, but with slightly less precision.
      6: Estimated (dead reckoning) fix.
      7: Manual input mode.
      8: Simulation mode.

- Number of Satellites in Use: Shown in digits.

- HDOP: Horizontal Dilution of Precision, a measure of the geometrical effect of satellite positioning on the accuracy of the GPS data.

- Altitude: The height of the device above mean sea level.