Search results for: satnogs

A Seminar on Setting up and Understanding a SatNOGS Satellite Ground Station

At the 2019 TAPR Digital Communications Conference (DCC), Corey Shields (KB9JHU) and Dan White (AD0CQ) presented a comprehensive guide on setting up your own SatNOGS satellite ground receiver station. The video of the presentation has just recently been uploaded to YouTube by Ham Radio 2.0.

SatNOGS is an open source project that aims to make it easy for volunteers to build and run satellite ground stations (typically based on RTL-SDR and Raspberry Pi hardware) that automatically receive RF satellite data, and automatically upload that data to the internet for public access. This is very useful for low budget cubesats launched by schools and small organizations who don't have the resources to run a worldwide satellite ground station network. Without global ground stations the majority of data and telemetry collected by the satellite could be lost as it would only pass over the owners ground station once or twice a day with limited time and bandwidth to downlink data. SatNOGS volunteers with distributed ground stations placed all over the world provide a free solution for this problem. 

Setting up a SatNOGS station and understanding the data coming down can be a pretty involved project, so Corey and Dan's 3.5 hr presentation gently guides us through the steps required. The guide focuses most on the software side, and does not include information about building their open source Yagi antenna rotator which can be used to receive satellites with lower power weak signals. Instead they focus on using a simpler fixed QFH antenna which is still capable of receiving data from a majority of satellites.

Learn to build and operate your own SatNOGS ground station. The Sunday Seminar is somewhat like the "anchor" topic of the entire weekend of the TAPR Digital Communications Conference. In 2019 we had the privilege of hearing from Corey, KB9JHU and Dan AD0CQ from the SatNOGS Team and they are going to give us, in detail, instructions for setting up a home satellite station.

(2:38) Intro
(7:46) Section 1: Satellite Building 101
(1:14:50) Section 2: Using SatNOGS
(2:19:55) Section 3: API and Contributing
(2:51:55) Section 4: RF Stack and Decoders

SatNOGS Ground Station Building Guide from TAPR DCC 2019

A Wall Mounted SatNOGS Ground Station Monitor

If you weren't already aware,  SatNOGS is an open source project that aims to make it easy for volunteers to build and run RF ground stations (typically based on RTL-SDR hardware) that automatically monitor satellite data, and upload that data to the internet for public access. This is very useful for low budget cubesats launched by schools/small organizations that don't have the resources for a worldwide monitoring network as data can be collected from all over the world no matter where the satellite is.

Over on the SatNOGS Libre Space forums, user cshields have posted about his near wall mounted SatNOGS monitoring station. With the station he's able to monitor the status of his SatNOGS station via an LCD screen and see the location of satellites that next in the queue to be received. There are also some status lights and LCD text screen for monitoring the SatNOGS rotator hardware.

The station consists of a Raspberry Pi 4, 7" LCD display, 500 GB SSD, RTL-SDR Blog V3, and an Arduino with 16x2 LCD and NeoPixel. cshields post covers the full details of the build.

[Also seen on Hackaday]

SatNOGS Ground Station Monitor
SatNOGS Ground Station Monitor

HackSpace Magazine Discusses SatNOGS, Cubesats and More

HackSpace is a monthly magazine dedicated to modern maker projects. This month issue 18 was released and it focuses on space based projects. The HackSpace Magazine is available for free online in PDF form, and physical copies can also be purchased.  There are several interesting articles but one in particular shows us how to set up a SatNOGS ground station with a Raspberry Pi 3, RTL-SDR and a satellite antenna such as a turnstile. 

A problem with low cost satellites like cubesats is that it is difficult to monitor them as data can only be collected when they are passing over a ground station. So in areas with no ground stations data is simply lost. SatNOGS is an open source project that aims to make it easy for volunteers to build and run RF ground stations that automatically monitor satellite data, and upload that data to the internet for public access. SatNOGS ground stations typically use RTL-SDR dongles as the radio.

A related article in the magazine also discusses cubesats, giving an overview of some previous cubesat launches and what sort of payloads are available. A third article under the space topic discusses the Libre Space Foundation which is the team behind the SatNOGS and various other space based projects that aim to democratize space. Readers may also be interested in the articles showing how to build an ISS countdown timer and how to build a Slim Jim antenna.

HackSpace Magazine SatNOGS Article
HackSpace Magazine SatNOGS Article (Excerpt)

Demonstration of Two SatNOGS Rotators

Thank you to IZ5RZR for writing in and sharing his two SatNOGS rotator builds with usSatNOGS is an open source project that aims to make it easy for volunteers to build and run RTL-SDR or other SDR based RF ground stations that automatically monitor satellites, and upload that data to the internet for public access.

IZ5RZR writes that he's now made two rotators and one was modified to use a 5:18 stepper motor (which is upgradable to 50:1) to give more torque so that heavier antennas can be turned smoothly. His rotators are powered by a 12V battery charged by solar, and they can be controlled over WiFi with a PC/tablet/phone. He's also tested the rotators with a 24 dB parabolic grid antenna and found that the rotator could handle it even without a counterweight. He also notes that together with IK5XWA they've fixed a "Meridian Flip" bug in the firmware.

The video below shows the two rotators in action.

IZ5RZR Two SatNOGS Satellite Rotators

Using a 25 Meter Radio Dish and an RTL-SDR as a SatNOGS Ground Station

SatNOGS is an open source project that aims to make it easy for volunteers to build and run RTL-SDR or other SDR based RF ground stations that automatically monitor satellites, and upload that data to the internet for public access. The antennas used in a typical home based SatNOGS station are small enough for a single person to handle, however recently the SatNOGS team have been working on setting up a monitoring station at the Dwingeloo Radio Observatory in the Netherlands.

Dwingeloo has a large 25 meter satellite dish antenna, and they connect it to an RTL-SDR on a laptop running the SatNOGS software. In the video they show it tracking the PRISM amateur radio satellite, and note that the use of this large dish will only be used in special circumstances. They write:

This week the Dwingelooradio Observatory tested their 25 meter dish as a SatNOGS station! Although not set up as a permanent SatNOGS station it is great to see this historic observatory linked to the network. Dwingeloo radio observatory was built between 1954 and 1956 near the village of Dwingeloo in the Netherlands. Since 2009 this single 25 meter dish has been a national heritage site.

Dwingeloo Radio Observatory as a SatNOGS 📡 station

Dwingleloo Satellite Antenna in the Netherlands
Dwingleloo Satellite Antenna in the Netherlands [Source: Wikipedia]

Art from Satellite Transmissions: SatNOGS and Software Defined Radio used in a Sound Art Installation

One of the piezo speakers playing the satellite transmissions.
One of the piezo speakers playing the satellite transmissions.

In the past we've seen software defined radio's like the HackRF use to create art installations such as the 'Holypager', which was an art project that aimed to draw attention to the breach of privacy caused by pagers used by doctors and staff at hospitals.

Recently another art installation involving a software defined radio was exhibited at Wichita State University. The project by artist Nicholas A. Knouf is called "they transmitted continuously / but our times rarely aligned / and their signals dissipated in the æther" and it aims to collect the sounds of various satellite transmissions, and play them back using small piezo speakers in the art gallery. To do this he built a SatNOGS receiver and used a software defined radio to capture the audio. He doesn't mention which SDR was used, but most commonly RTL-SDR's are used with the SatNOGS project. Nicholas describes the project below:

This 20-channel sound installation represents the results of collecting hundreds of transmissions from satellites orbiting the earth. Using custom antennas that I built from scratch, I tracked the orbits and frequencies of satellites using specialized software. This software then allows me to collect the radio frequency signals and translate them into sound.

The open source software and hardware, called SatNOGS and developed by a world-wide group of satellite enthusiasts, enables anyone to build a ground station for tracking satellites and their transmissions, which are then uploaded to a publicly accessable database. Data received by my ground stations can be found here. These transmissions are mostly from weather satellites, CubeSats (small satellites launched by universities world-wide for short-term research), or amateur radio repeaters (satellites designed for ham radio operators to experiment with communication over long distances).

I made the speakers hanging from the grid from a piezoelectric element embedded between two sheets of handmade abaca paper that was then air dried over a form.

The project was also discussed over on the SatNOGS forum.

The SatNOGS art installation
The SatNOGS art installation

FOSDEM 2017/2018 SDR Conference Videos: Passive Radar, Radio Telescopes, SatNOGS and Wireless Traffic Lights

Fosdem 2017 and 2018 were conferences on software development that occurred on 4 & 5 February 2017 and 3 & 4 February 2018. The conference features several software defined radio and RTL-SDR based talks which appear to have recently been uploaded to YouTube. Below we're posting some of our favorite SDR related talks, but the full video list can be found here, and here is the SDR playlist from Fosdem 2018.

(Yet another) passive RADAR using DVB-T receiver and SDR

by Jean-Michel Friedt @ FOSDEM 2018

In this presentation Jean-Michel shows a GNU Radio passive radar implementation utilizing two coherent RTL-SDR dongles. During the talk he demonstrates his results with RTL-SDR passive radar operating on planes, boats and cars.


(Yet another) passive RADAR using DVB-T receiver and SDR.

Intro to Open Source Radio Telescopes

by Martin Braun and Sue Ann Heatherly @ FOSDEM 2018

In this talk Martin and Sue discuss how amateur radio astronomy can be performed using lost cost software defined radio tools such as an RTL-SDR. They show how to receive solar flares and detect the 21cm hydrogen line and focus on showing how easy it can be to do these projects in a classroom environment.

Intro to Open Source Radio Telescopes

Claim Space, the Libre Way, using SDRs

by Manolis Surligas @ FOSDEM 2018

In this talk Manolis from the Libre Space Foundation and SatNOGs discusses how they use RTL-SDR's and other SDR's in their volunteer run network of satellite ground stations to create an online database of received satellite data.

Claim Space, the Libre Way, using SDRs

Receiving Wireless Mobile Traffic Lights

by Bastian Bloessl @ FOSDEM 2017

Wireless mobile traffic lights are often used to secure construction sites when roads are partially blocked. Some day, when a pair of them was placed close to our home, I set off to explore how they are working. In this talk, I will describe how I used a cheap RTL-SDR together with GQRX, Inspectrum, and GNU Radio to reverse engineer the modulation and frame format of different types of wireless traffic lights. With some patience, I could also make some sense out of the bits. In particular, I was able to extract the signal state and display it in a web interface, mirroring the traffic light. A closer look at the frame format and the apparent absence of any authentication might leave one with a bit of a worrying impression regarding the security of those systems.

Receiving Wireless Mobile Traffic Lights

SDR and Radio Talks from the 34th Chaos Communication Congress: SatNOGs, Bug Detection, GSM with SDR, Open Source Satellites and WiFi Holography

Every year the Chaos Computer Club hold the Chaos Communication Congress (CCC) which is a conference that aims to discuss various topics related to technology and security. This year was the 34th conference ever held (34C3) and there were several interesting SDR and radio related talks which we post below. Further links and video downloads are available in the YouTube description.

SatNOGS: Crowd-sourced satellite operations

An overview of the SatNOGS project, a network of satellite ground station around the world, optimized for modularity, built from readily available and affordable tools and resources.

We love satellites! And there are thousands of them up there. SatNOGS provides a scalable and modular platform to communicate with them. Low Earth Orbit (LEO) satellites are our priority, and for a good reason. Hundreds of interesting projects worth of tracking and listening are happening in LEO and SatNOGS provides a robust platform for doing so. We support VHF and UHF bands for reception with our default configuration, which is easily extendable for transmission and other bands too.

We designed and created a global management interface to facilitate multiple ground station operations remotely. An observer is able to take advantage of the full network of SatNOGS ground stations around the world.

34C3 - SatNOGS: Crowd-sourced satellite operations

Spy vs. Spy: A Modern Study Of Microphone Bugs Operation And Detection

In 2015, artist Ai Weiwei was bugged in his home, presumably by government actors. This situation raised our awareness on the lack of research in our community about operating and detecting spying microphones. Our biggest concern was that most of the knowledge came from fictional movies. Therefore, we performed a deep study on the state-of-the-art of microphone bugs, their characteristics, features and pitfalls. It included real life experiments trying to bug ourselves and trying to detect the hidden mics. Given the lack of open detection tools, we developed a free software SDR-based program, called Salamandra, to detect and locate hidden microphones in a room. After more than 120 experiments we concluded that placing mics correctly and listening is not an easy task, but it has a huge payoff when it works. Also, most mics can be detected easily with the correct tools (with some exceptions on GSM mics). In our experiments the average time to locate the mics in a room was 15 minutes. Locating mics is the novel feature of Salamandra, which is released to the public with this work. We hope that our study raises awareness on the possibility of being bugged by a powerful actor and the countermeasure tools available for our protection.

34C3 - Spy vs. Spy: A Modern Study Of Microphone Bugs Operation And Detection

Running GSM mobile phone on SDR

Since SDR (Software Defined Radio) becomes more popular and more available for everyone, there is a lot of projects based on this technology. Looking from the mobile telecommunications side, at the moment it's possible to run your own GSM or UMTS network using a transmit capable SDR device and free software like OsmoBTS or OpenBTS. There is also the srsLTE project, which provides open source implementation of LTE base station (eNodeB) and moreover the client side stack (srsUE) for SDR. Our talk is about the R&D process of porting the existing GSM mobile side stack (OsmocomBB) to the SDR based hardware, and about the results we have achieved.

There is a great open source mobile side GSM protocol stack implementation - OsmocomBB project. One could be used for different purposes, including education and research. The problem is that the SDR platforms were out of the hardware the project could work on. The primary supported hardware for now are old Calypso based phones (mostly Motorola C1XX).

Despite they are designed to act as mobile phone, there are still some limitations, such as the usage of proprietary firmware for DSP (Digital Signal Processor), which is being managed by the OsmocomBB software, and lack of GPRS support. Moreover, these phones are not manufactured anymore, so it's not so easy to find them nowadays.

Taking the known problems and limitations into account, and having a strong desire to give everyone the new possibilities for research and education in the telecommunications scope, we decided to write a 'bridge' between OsmocomBB and SDR. Using GNU Radio, a well known environment for signal processing, we have managed to get some interesting results, which we would like to share with community on the upcoming CCC.

34C3 - Running GSM mobile phone on SDR

UPSat - the first open source satellite

During 2016 Libre Space Foundation a non-profit organization developing open source technologies for space, designed, built and delivered UPSat, the first open source software and hardware satellite.

UPSat is the first open source software and hardware satellite. The presentation will be covering the short history of Libre Space Foundation, our previous experience on upstream and midstream space projects, how we got involved in UPSat, the status of the project when we got involved, the design, construction, verification, testing and delivery processes. We will also be covering current status and operations, contribution opportunities and thoughts about next open source projects in space. During the presentation we will be focusing also on the challenges and struggles associated with open source and space industry.

34C3 - UPSat - the first open source satellite

Holography of Wi-Fi radiation

Can we see the stray radiation of wireless devices? And what would the world look like if we could?

When we think of wireless signals such as Wi-Fi or Bluetooth, we usually think of bits and bytes, packets of data and runtimes.

Interestingly, there is a second way to look at them. From a physicist's perspective, wireless radiation is just light, more precisely: coherent electromagnetic radiation. It is virtually the same as the beam of a laser, except that its wavelength is much longer (cm vs µm).

We have developed a way to visualize this radiation, providing a view of the world as it would look like if our eyes could see wireless radiation.

Our scheme is based on holography, a technique to record three-dimensional pictures by a phase-coherent recording of radiation in a two-dimensional plane. This technique is traditionally implemented using laser light. We have adapted it to work with wireless radiation, and recorded holograms of building interiors illuminated by the omnipresent stray field of wireless devices. In the resulting three-dimensional images we can see both emitters (appearing as bright spots) and absorbing objects (appearing as shadows in the beam). Our scheme does not require any knowledge of the data transmitted and works with arbitrary signals, including encrypted communication.

This result has several implications: it could provide a way to track wireless emitters in buildings, it could provide a new way for through-wall imaging of building infrastructure like water and power lines. As these applications are available even with encrypted communication, it opens up new questions about privacy.

34C3 - Holography of Wi-Fi radiation