# Simulation with MAVLink protocol **URL:** \ **Category:** GNU Radio\ **Created:** [June 27, 2014, 11:34pm UTC](https://www.ruby-forum.com/t/simulation-with-mavlink-protocol/230653 "2014-06-27T23:34:03Z")\ **Posts on this page:** 5\ **Page:** 1
**Author:** ![jason\_sam](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/j/7993a0/32.png) [@jason\_sam](https://www.ruby-forum.com/u/jason_sam)\ **Post date:** [June 27, 2014, 11:34pm UTC](https://www.ruby-forum.com/t/simulation-with-mavlink-protocol/230653/1 "2014-06-27T23:34:03Z")
Hello, I have some needs and I’d like to know if GnuRadio can help me with it. I have already read some material at GR website and I didn’t get the answer.I need to receive and send packets with a specific protocol called MAVLink, used in mini UAVs. More specifically I am thinking about developing a sniffer.I don’t have sdr hardware for now, then for starting I am thinking on simulation. My doubts are as follows: - Is it possible to implement a new protocol for sending and receive packets? (MAVLink protocol) - My idea is to simulate the exchange between a UAV and a control ground station. Would it possible to do it? Thanks in advance. ---
**Author:** ![Paulo\_Roberto](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/p/8dc957/32.png) [@Paulo\_Roberto](https://www.ruby-forum.com/u/Paulo_Roberto)\ **Post date:** [June 28, 2014, 2:58am UTC](https://www.ruby-forum.com/t/simulation-with-mavlink-protocol/230653/2 "2014-06-28T02:58:07Z")
Hi Paulo, GNU Radio gives you but the framework to write and connect signal processing blocks, as well as a nice set of “standard” blocks. Among the functionalities available there are means to generate packets and process the same. If you know that if you can capture the signal, you could mathematically/algorithmically analyze it, it’s basically possible to implement this in GNU Radio. That being said, it’s not really easy to implement a complete packeted standard in GNU Radio since that might be a “logically” complex task, involving different modulations, synchronization, collision detection, arbitration, resend requests and much more. However, there are several examples of people being able to decode received signals. I like to point gr-ieee802-11 (WLAN packets _transceiver_), and for a “simpler” system gr-air-modes (air traffic control message decoding). Greetings, Marcus ---
**Author:** ![Paulo\_Roberto](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/p/8dc957/32.png) [@Paulo\_Roberto](https://www.ruby-forum.com/u/Paulo_Roberto)\ **Post date:** [June 29, 2014, 1:10am UTC](https://www.ruby-forum.com/t/simulation-with-mavlink-protocol/230653/3 "2014-06-29T01:10:17Z")
Hi! Of course it would be helpful if you had a capture device if your motivation was to capture signals of a system. Also, it will give you something to test your reception algorithms on. Greetings, Marcus ---
**Author:** ![Paulo\_Roberto](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/p/8dc957/32.png) [@Paulo\_Roberto](https://www.ruby-forum.com/u/Paulo_Roberto)\ **Post date:** [June 29, 2014, 7:09am UTC](https://www.ruby-forum.com/t/simulation-with-mavlink-protocol/230653/4 "2014-06-29T07:09:35Z")
Hey, I have the feeling that there maybe a misunderstanding about what MAVlink really is. The MAVlink protocol as such is serialization library that is used to transfer information, i.e. serialized data structures, between mobile and stationary devices rather than a whole “communication system”. You can transfer MAVlink messages over any kind of transport system such as Wifi, bluetooth, Zigbee or any proprietary system. So what you probably want is to receive and decode the communication of that transfer system, maybe using GR, and then decode the actual payload with the MAVlink library. Cheers Andre ---
**Author:** ![Paulo\_Roberto](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/p/8dc957/32.png) [@Paulo\_Roberto](https://www.ruby-forum.com/u/Paulo_Roberto)\ **Post date:** [June 29, 2014, 12:40pm UTC](https://www.ruby-forum.com/t/simulation-with-mavlink-protocol/230653/5 "2014-06-29T12:40:36Z")
Right, I’ve played with MAVlink before and as said it is not a wireless standard, you can send it over hard link serial if you want. I’m assuming your are sending the MAVlink over a pair of serial-RF adapters as is usual. [http://copter.ardupilot.com/wiki/common-using-the-3dr-radio-for-telemetry-with-apm-and-px4/](http://copter.ardupilot.com/wiki/common-using-the-3dr-radio-for-telemetry-with-apm-and-px4/) Seems to be what most use ( I have a pair of these as well ). If you look at the technical section your can see they list FHSS GFSK as the modulation. I would look into the datasheet for the chip for more details. I would recommend just doing the RF demodulation in GNUradio and then send the packets to an external program for further processing. ~Andrew On Sat, Jun 28, 2014 at 8:06 AM, Andre P. \<