Tagged: weather satellite

Testing a WiFi Grid Antenna for L-Band Satellites

Over on YouTube dereksgc has uploaded a video where he tests out a 2.4 GHz WiFi Grid antenna for L-band weather satellite reception. WiFi grid antennas are typically repurposed in the SDR community for L-Band weather satellite reception because they are cheap and mostly work out of the box. They can also be used for hydrogen line radio astronomy. TV dish antennas are an alternative but with them, a custom feed needs to be built. 

In his video, dereksgc tests the WiFi dish on receiving various polar-orbiting L-band satellites including Metop, and Meteor M2. With the polar orbiting satellites the dish needs to point at the satellite as it passes over the sky and so dereksgc recommends using a mount if hand tracking them.

Later in the video he tests some geostationary satellites but finds that the dish is not tuned well enough to receive Elektro-LN3 properly without modifications. He was however able to receive a noisy image from FengYun-2H successfully.

We note that we also currently have our Discovery Dish product available for pre-order, which is similar to the WiFi grid dish, but smaller and lighter weight with a built-in optimized active feed.

I finally got a WiFi grid antenna for satellites

Saveitforparts: Receiving and Decoding L-Band Weather Satellites

Over on his YouTube channel 'saveitforparts' has uploaded a new video showing how he has been successful at receiving and decoding L-band weather satellites using his setup made from scavenged parts. He uses a custom-built helical feed on a scavenged dish, and an automatic pan-tilt rotator built from an old security camera mount. With this setup combined with an RTL-SDR and LNA and filter he is able to receive polar orbiting L-band weather satellites. 

In the video, he shows how his system works and what his software setup looks like. He uses SDR++ to record the pass initially, then SatDump to decode the data into images. We note that SatDump can be used to decode the images live, and can also record the raw radio files too, so SDR++ is not required.

How To Receive And Decode L-Band Weather Satellites

IndiaRocketGirl Receives NOAA-19 Weather Satellite Images with a Tape Measure Yagi Antenna

Over on her YouTube channel IndiaRocketGirl (@VU3BIZ) has posted a video showing how she was able to receive weather satellite images from the polar orbiting NOAA-19 weather satellite at 137 MHz.

She uses a home made four element Yagi antenna with elements made from a tape measure. This allows the elements to be easily folded down for transportation. A phone running the Heaven's above app is used to help track the satellite in the sky as it passes over, and then SatDump and an RTL-SDR Blog V3 running on a laptop is used to decode the signal into an image.

IndiaRocketGirl notes that in her next video she will show how to make the Yagi antenna that she was using. In a previous post IndiaRocketGirl also showed how she was able to receive geostationary FengYun-2H S-VISSR signals.

How to Receive Real Time Images from Low Earth Orbit Satellites | India Rocket Girl | NOAA-19

IndiaRocketGirl Receives FengYun-2H S-VISSR Satellite Images

Over on her YouTube channel IndiaRocketGirl has posted a video showing how she was able to build a satellite dish and feed to receive FengYun-2H S-VISSR signals and get beautiful full disk images of the earth.

In the US and other countries RTL-SDR fans will be familiar with how to receive images from the GOES geostationary weather satellite. However from countries like India most GOES satellites will not be visible. Fortunately there are alternative satellites like the Chinese FengYun-2H satellite which is visible from India. FengYun-2H is a geostationary satellite that sends down a S-VISSR signal containing full disk images of the earth.

In her video IndiaRocketGirl uses a 1.8 meter diameter antenna, a homemade helical feed, an LNA+filter and an RTL-SDR as her hardware. For software she uses SatDump.

How to receive Real Time Images from Geostationary Satellites | RTL SDR | India Rocket Girl

Multiple Comprehensive Tutorials on Weather Satellite Decoding

Over on his website "Jacopo's Lair" IU1QPR (@original_lego11) who is also a developer for SatDump has written up many tutorials about weather satellite decoding that involve the use of SatDump. SatDump is a popular piece of software often used with RTL-SDRs and other low cost SDRs for decoding weather satellite images.

With a small satellite dish, feed, RTL-SDR and LNA+filter and the SatDump software it's possible and download beautiful images of the earth from many geostationary and polar orbiting weather satellites. We note that we are currently taking pre-orders on Crowd Supply for our Discovery Dish system, which is low cost hardware designed to help users get started with weather satellite reception.

Over on Reddit IU1QPR has created a listed summary of all the tutorials he's written. These are currently the most up to date and comprehensive tutorials that we have found on this topic. The tutorials cover everything from what satellites are available, what dish sizes you need, what SDRs can be used, what LNA+filter and other hardware you need, and how to use the SatDump software.

Satellite reception and decoding

Automated stations

SatDump usage

All have been moved to SatDump's documentation page

Satellite data processing and usage

From the HRPT tutorial: What various HRPT signals look like on the spectrum.
From IU1QPR's HRPT tutorial: What various HRPT signals look like on the spectrum.

Downloading Stored Images and Data from the NOAA Weather Satellite GAC Broadcast

With polar orbiting weather satellite reception we as amateur ground station operators with SDR receivers typically download images via "Direct Broadcast", which provides imagery of what the satellite is currently seeing live. However, the main way satellites such as the NOAA POES (NOAA 15, 18 & 19) satellites downlink is via "Global Area Coverage" (GAC) broadcast which provides the full stored imagery data of the entire global pass. However, GAC is only broadcast in locations where the satellite operator operates ground stations.

Over on YouTube dereksgc has uploaded a video showing how to receive GAC data from the NOAA POES satellites. He notes that GAC is now broadcast at 2247.5 MHz in the S-band, and the ground station it now downlinks to is likely in Svalbard, rather than in the USA. This means that amateur satellite stations close to the North Pole can receive the GAC signal, including dereksgc's station which (we believe) is in the Czech Republic.

Dereksgc uses a large 250cm offset dish with S-band feed connecting to a HackRF. In the video he demonstrates him receiving the signal, and then decoding it using SatDump. Finally he shows all the images from various locations around the earth that he was able to receive from one satellite pass.

Downloading stored data from NOAA weather satellites (GAC revisited) || Satellite reception pt.12B

Crowd Supply Discovery Dish Teardown Session: Thursday 30 November Noon PST

Crowd Supply is hosting Teardown Session 38 on Thursday 3- November at Noon PST time which will feature the Discovery Dish. Join us for this livestream where I will be talking about and showing the Discovery Dish prototype.

Discovery Dish is currently being crowd funded over on Crowd Supply. It is designed to be an easy entry to the world of L-band weather satellites, hydrogen line radio astronomy, and Inmarsat reception. The Discovery Dish aims to be the start of an ecosystem of hardware designed to get users set up with satellite reception, including a planned companion light-duty antenna rotator.

Remember to click on the “Notify me” button on the YouTube link in order to be reminded about the stream!

Teardown Session 38: Discovery Dish

Saveitforparts: Building an L-Band Satellite Antenna out of an Umbrella

Over on his YouTube channel "saveitforparts" has uploaded a video where he uses an umbrella, pin tin and tin foil tape to create a simple dish antenna for receiving GOES, NOAA and METEOR HRPT satellites.

The full build consists of an umbrella covered in tin foil tape, a helical wire feed on a pie tin, a filtered LNA, an RTL-SDR and an Android phone running SDR++. While he did have initial success at receiving, he soon decided to swap out the helical wire feed for a PCB linear feed instead which worked much better as helical feeds can be very difficult to get right.

Through the video saveitforparts goes over the failures he had, in the end noting that it's not a great antenna, but it's something that can be used in a pinch.

We've also seen the umbrella satellite dish used a few times in the past, where here it was used for NOAA APT reception, and here for Hydrogen Line radio astronomy.

We also want to remind readers that we are currently Crowd Funding for our Discovery Dish, which will be a low cost way to get into L-band satellite reception.

Can I Get Satellite Data With An Umbrella?