Tagged: weather satellite

Standalone Windows FengYun-3 & MetOp HRPT Weather Satellite Decoder

Back in June we posted about Alan (@aang254)'s work on porting the GNU Radio gr-hrpt decoder over to GNU Radio 3.8. More recently Alan wrote in and wanted to share the news that he has recently released standalone Windows decoders for the MetOp and FengYun-3 weather satellites.

MetOp and FengYun-3 are both polar orbiting satellites that beam back high resolution weather satellite images. Unlike the NOAA polar orbiting satellites which transmit both the easy to receive APT and more advanced HRPT signal, these only transmit a HRPT signal at ~1.70 GHz, so a satellite dish and motorized tracking mount (or hand tracked) is required. You will also need an SDR capable of receiving over 3 MHz bandwidth such as an Airspy Mini or R2. Alan writes:

I recently got FengYun decoding working after the release of my MetOp decoder a while ago. Since gr-hrpt wasn't usable for Windows user without some major hassle, I made some standalone decoders (Windows builds included in the repo) for both MetOp and FengYun.

Decoding is done by first demodulating with the included flowcharts or @petermeteor's, then processed through the decoder which does Viterbi / Differential decoding. The output then needs to be deframed by MetFy3x or any other software that can do so.

https://github.com/altillimity/Satellite-Decoders

A few images!

https://twitter.com/SamuelArmstro18/status/1285647473881513989
https://twitter.com/ZSztanga/status/1285277472284708865
https://www.reddit.com/r/amateursatellites/comments/hwhb7q/my_longest_fy3b_image_yet_i_got_up_at_430_in_the/
https://twitter.com/HA6NAB_Tomi/status/1285300023350222848
https://twitter.com/ub1qbj/status/1286734822820532224/photo/1

You can learn more about these satellites on USA-Satcom's Cyberspectrum talk and slides.

A Simple Guide to Setting up a DIY NOAA Weather Satellite Ground Station

A few weeks ago we posted about Sophie Dyer and Sasha Engelmann's work in creating an artistic performance based on weather satellite reception with SDRs. More recently they have uploaded their own tutorial showing how they receive NOAA APT weather satellite images with an SDR, turnstile antenna and computer. Sasha and Sophie note that they are attempting to create visually rich guides that don't assume any prior knowledge of radio, science or engineering.

From Sasha's Twitter feed we note that they are also working on upcoming public workshops in the UK and Germany on the topic of reflections on what it means to bring an intersectional feminist ethos to satellite image decoding + weather sensing, & new creative collaborations in 2020. If you are interested in their work please follow @sashacakes and @sophiecdyer on Twitter.

Receiving NOAA weather satellites
Receiving NOAA weather satellites

Open Weather: An Artistic Performance Involving Live NOAA APT Signal Decoding for Sound Arts Festival

Just after our post a few days ago about an art project involving weather satellite reception with SDRs, we received a story submission about an artistic performance with similar weather satellite and SDR themes. The submission from Sasha Engelmann reads:

Open Work, Second Body is a live-streamed performance by designer Sophie Dyer (@sophiecdyer) [M6NYX] and geographer Sasha Engelmann (@sashacakes) [M6IOR] in collaboration with the author Daisy Hildyard. The work was performed twice during Reveil 2020, a global sound arts festival streaming sounds from listening points around the planet on the day of the International Dawn Chorus.

Open Work, Second Body asks: From the climate crisis to coronavirus: what are the tools we need to make sense of events unfolding on vastly disparate scales? Through spoken word, field recordings and live radio reception of two NOAA satellite images, the work probes the porous boundaries between our bodies, local atmospheres and weather systems.

Still image capture from livestream of Open Work, Second Body, AM performance, May 2nd 2020

Due to lockdown constraints in London, Sophie and Sasha were not able to be in the same place or to leave their apartments, so they performed the work via simultaneous streams from their respective balconies in South East and North West London. Using RTL-SDRs, Turnstile antennas, Open Broadcast Software and collaborating with two NOAA satellite passes, Sophie and Sasha shared the process of decoding NOAA satellite images with hundreds of viewers around the world, employing spoken word poetry and field recordings to complicate relationships of local and global, weather and climate, the individual and the collective. 

Recordings of the performances can be found at the links below. 

☀️Morning: https://youtu.be/-5JrxwNpJqI [performance starts at 05:25]
?️ Afternoon: https://youtu.be/h88zaCtX8cw [performance starts at 05:00]

Still image capture from livestream of Open Work, Second Body, PM performance, May 2nd 2020
Still image capture from livestream of Open Work, Second Body, PM performance, May 2nd 2020

Open Work, Second Body is part of Sophie and Sasha's larger artistic research and design project Open Weather, which employs ham radio, open data and feminist theories and approaches to build new and diverse communities around satellite image decoding and weather sensing. The Open Weather web platform will be launched in Summer 2020 and will host an archive of SDR-generated weather images, visually rich how-to guides for those with no radio and engineering experience, and material about Sophie and Sasha's collaborative artistic practice. 

For Open Work, Second Body, Sophie and Sasha would like to thank the Soundcamp Team: Grant Smith, Dawn Scarfe, Christine Bramwell, Maria Papadomanolaki and Ciara Drew. They are grateful to Daisy Hildyard for her willingness to be in conversation with them, Bill Liles NQ6Zfor technical advice, Jol Thoms for sound design, Rachel Dedman, Laure Selys and Arjuna Neuman (Radio Earth Hold) for early curatorial input, Akademie Schloss Solitude for the support of a residency, the satellites NOAA 18 and NOAA 19 and the RTL-SDR and wider ham radio community. 

http://www.sophiedyer.net

http://www.sashaengelmann.com

It's very cool to see technical hobbies like ours starting to make an impact in art and reaching a wider audience. More content and images available on Sophie's Open Weather webpage, and Sasha's Open Weather webpage

Open Weather Live Stream

Decoding HIRS Instrument Images from NOAA Weather Satellites

Thank you to Björn Schnabel who has written in to notify us about a website he's created for a program written by Zbigniew Sztanga called NOAA-HIRS-decoder which might be of interest to some RTL-SDR users. Most of us are familiar with the the ability to use an RTL-SDR to receive the APT signal on the NOAA 15/18/19 weather satellites. The APT signal provides a live image of the Earth. If you haven't tried to receive APT yet, we have a tutorial here.

Apart from APT there is also the HIRS instrument data which is transmitted in the Direct Sounding Broadcast (DSB) telemetry signal that is spaced at a slight offset from the APT frequency. According to NOAA, the HIRS instrument is "a discrete stepping, line-scan instrument designed to measure scene radiance in 20 spectral bands to permit the calculation of the vertical temperature profile from the Earth's surface to about 40 km". The SDR# screenshot below shows what the HIRS signal looks like, and to the sides you can see NOAA APT signals.

The NOAA HIRS Signal
The NOAA HIRS Signal (Center Signal)

NOAA-HIRS-decoder makes use of the Project-Dessert-Tortoise NOAA satellite telemetry decoder that we posted about previously which can be used to decode data from most of the other scientific instruments on the NOAA satellites. The HIRS decoder by Zbigniew uses the raw text data produced by the Project-Dessert-Tortoise decoder and converts it into images. Full instructions on setting up the decoder on Windows is provided on the NOAA-HIRS-decoder website, just click the menu icon on the top right of the page, and go to "usage".

The received data contains 10 channels of long wave infrared, 9 channels of medium wave infrared, and one visible light measurement. The software will plot the 20 channels as images that are 56 pixels wide. This is not a high resolution picture, but it is nevertheless valuable data that can be used for scientific or weather prediction purposes.

All 20 NOAA HIRS Channels (Image enlarged from 56 pixels)
All 20 NOAA HIRS Channels (Image enlarged from 56 pixels)

Techminds: Building a V-Dipole for Weather Satellite Reception

A new video showing how to build a V-dipole for weather satellite reception has been uploaded over on the Tech Minds YouTube channel. A V-dipole isa dipole antenna arranged in a 120 degrees "vee" shape, and mounted horizontally. It was first popularized by Adam 9A4QV who realized that such a simple antenna would work well for low earth orbit satellites like the NOAA and Meteor weather sats.

The video shows how to use some steel rods, a plastic pipe and terminal block to build the v-dipole. After building and mounting the antenna in the required North-South orientation he shows how he's using Gpredict with SDR# and WxToImg to decode the NOAA satellite image.

How To Build A V Dipole For Receiving Weather Satellites

YouTube Tutorial on Receiving Weather Images from NOAA Satellites

Over on YouTube the "Ham Radio Crash Course" channel has uploaded a new video showing how to receive APT images from NOAA weather satellites. There are many tutorials (such as ours here) and videos on this topic already, but more cannot hurt, and this one makes specific reference to how to download the WXtoIMG software now that the official website has been abandoned.

In the tutorial he uses an SDRplay with SDRuno as the receiver software, VBCable as the audio piping software, and WXtoIMG as the decoding software.

How To Receive Images Directly From NOAA Satellites

Meteor-M N2-2 Weather Satellite Updates: No More 137 MHz LRPT, L/X-Band Working in Daylight

In late December 2019 we posted about Russian weather satellite Meteor M N2-2 which had unfortunately been struck by a micro-meteorite on Dec 18, causing it to lose control and go offline. Meteor M N2 and N2-2 satellites are often monitored with RTL-SDR dongles as it is relatively simple to receive their LRPT signal at 137 MHz which contains a high resolution weather satellite image.

Recently Happysat updated his Meteor M status page, noting that Meteor M N2-2 has been partially recovered, but due to low power it can no longer transmit a 137 MHz LRPT signal ever again. However, the L and X-bands are transmitting while the satellite is in daylight. Happysat writes:

January 2020 There will be only short-term power-ups in the radio visibility zone, and the battery life will be reduced tenfold.

Of particular concern are the batteries they are very quickly overheated and switching from regular to backup.

Unfortunately the power supply features do not allow the 137 MHz transmitter to be used in abnormal power, mode (from solar panels) which is used now although technically it is working fine.

There will be no LRPT Transmission's anymore.

The older Meteor M N2 satellite remains operational transmitting at 137.100 MHz.

The Meteor-M2 Satellite
The Meteor-M N2 Satellite

Meteor M N2-2 Has Failed but Recovery May be Possible

UPDATE: It has now been confirmed by Roscosmos that the satellite was struck by what is presumed to be a micrometeorite which caused a leak of thermal transfer gas, and hence a sudden orbit change. It seems unlikely that the satellite will begin operations again as the satellite cannot operate it's camera sensors without thermal cooling. Data is being transmit currently on the X-Band, however, it appears to be a stored image only, rather than live images.

On December 18, 2019, an abnormal situation was recorded on the Meteor-M spacecraft No. 2-2 associated with an external impact (presumably a micrometeorite) on its structure. As a result, he changed the parameters of the orbit and switched to a non-oriented flight mode with high angular velocities.

In accordance with the inherent logic of operation, the device stopped fulfilling the target task and automatically switched to energy-saving mode when the on-board systems that were not involved in ensuring its functioning (including all on-board target equipment) are turned off.

After entering into the zone of Russian ground-based controls with the Meteor-M spacecraft No. 2-2, communication was established and work began to restore its operability: damping angular velocities, transferring to the standard orientation, receiving telemetric and target information.

Currently, work is underway with the satellite under the program of the chief designer. Meteor-M No. 2-2 is in an oriented flight; regular control sessions are conducted with it to receive telemetric information and information from target equipment.

Happysat's Notes:

Depressurization caused gas that was inside and used for heat transfer to leak out.

Resulting in some devices onboard overheating, while others did stop working.

Batteries are working under harsh thermal conditions.

Experts analyzing MSU-MR images during the incident to confirm collision.

------------------------- Original Post -------------------------

On December 18 Meteor M N2-2 suffered a failure that appears to have changed it's orbit. Roscosmos is quiet on the issue, but speculation by R4UAB is that there was a depressurization or on board explosion. However, Happysat who appears to be in contact with Roscosmos insiders has noted that on December 20 the orbit has been stabilized, and that they are working on recovering the operation of the satellite. Currently the LRPT signal and all sensors remain OFF.

Meteor M N2-2 is a Russian weather satellite that was successfully launched into orbit on July 5 2019. Like with the NOAA and Meteor M N2 satellites, it is possible to receive weather satellite images from this satellite with an RTL-SDR (when it is operational).

The older but still operational Meteor M2 satellite has failed several times in it's history too, each time with the satellite entering an unstable tumble. However, each time the satellite was recovered back into full operation after a few days.

The Meteor-M2 Satellite
The Meteor-M N2-2 Satellite