[comment]: # ( SPDX-License-Identifier: BSD-3-Clause ) [comment]: # ( SPDX-FileCopyrightText: 2021 Carles Fernandez-Prades ) # nav_msg_listener Simple application that retrieves decoded navigation messages produced by GNSS-SDR and prints them in a terminal. This is only for demonstration purposes, as a example on how to retrieve data using the `nav_message.proto` file. # Build the software This software requires [Boost](https://www.boost.org/) and [Protocol Buffers](https://developers.google.com/protocol-buffers). In a terminal, type: ``` $ mkdir build && cd build $ cmake .. $ make ``` ## Usage In order to tell GNSS-SDR to generate those messages, you need to include the lines: ``` NavDataMonitor.enable_monitor=true NavDataMonitor.client_addresses=127.0.0.1 ; destination IP NavDataMonitor.port=1237 ; destination port ``` in your gnss-sdr configuration file. You can specify multiple destination addresses, separated by underscores: ``` NavDataMonitor.client_addresses=79.154.253.31_79.154.253.32 ``` Run gnss-sdr with your configuration, and at the same time, from the computer of the client address (or another terminal from the same computer that is executing gnss-sdr if you are using `127.0.0.1`), execute the binary as: ``` $ ./nav_msg_listener 1237 ``` where `1237` needs to be the same port as in `NavDataMonitor.port`. As soon as gnss-sdr starts to decode navigation messages, you will see them in your terminal: ``` $ ./nav_msg_listener 1237 New Data received: System: E Signal: 1B PRN: 11 TOW of last symbol [ms]: 75869044 Nav message: 000000001001010101010101010101010101010101010101010101010101010101010101010101010101010101010101010011100101110001000000 New Data received: System: G Signal: 1C PRN: 16 TOW of last symbol [ms]: 75870000 Nav message: 100010111010101010101000101111000110001011001010010100011100010001000000000000000000000011010100000000101101100001000011000000000000000000000000111111101000010000110110011011000100000101111100000111100110110101000100110100100010011011101001001010011001011111111110000110000000000000000000000010001100 New Data received: System: E Signal: 5X PRN: 18 TOW of last symbol [ms]: 75870260 Nav message: 0000100001111110010000010111110100011010010000100000000000000000000000000000000000000000000000000000000010101010000001001011010010100100100100100110101110110101010000100000000000000000111001011100010010100001010100001110101001001101111000000000 New Data received: System: G Signal: L5 PRN: 6 TOW of last symbol [ms]: 75871320 Nav message: 100010110001100011110001100010110010100111100001110100001000000110110101100101011100110111001101100001011001110110010100101110001000000010000000100000001000000010000000100000001000000010000000100000001000000010000000100000001000000010000000100000001000000010000000100000001000001010101010111110000000 ```