Software Overview:
Predict – Utility to calculate satellite azimuth and elevation using TLE Kep elements
rtl_fm – SDR fm Demodulation Utility to decode your ATP Satellite signal to audio file.
Sox – To convert row Audio file into format for wxtoimg to convert to Satellite Image.
Shell script to calculate the schedule for enabling the rtl receiver.
wxtoimg – Utility that converts ATP Audio files into Satellite Images.
Apache server to expose the images to the internet.
Automated Weather Satellite Ground Station:
Antenna:
http://lna4all.blogspot.com/2017/02/diy-137-mhz-wx-sat-v-dipole-antenna.html
https://www.antenna-theory.com/antennas/halfwave.php#:~:text=One%20wavelength%20at%20600%20MHz,t%20like%20the%20metric%20system).
1/2 Wavelength Horizontal V-dipole
L(m) = 147 / F(MHz)
L(m) = 147 / 137.5
L = 1.068 m = 106.8cm
Each leg = 53.4 cm
Antenna Kit
$16-
Raspberry Pi NOAA Weather Satellite Receiver:
Step By step Instructions
https://www.instructables.com/Raspberry-Pi-NOAA-Weather-Satellite-Receiver/
BIAS-T:
SDRs with built-in bias tees:
|—————————————————————|
|SDR |Bias Tee |Bias Tee |Over-current |
| |Voltage (V) |Current (mA) |Protection |
|—————|—————|—————|—————|
|RTL-SDR | 4.5 | 180 | Yes |
|HackRF | 3.3 | 50 | ? |
|SDRPlay RSPdx | 4.7 | 100 | Yes |
|—————————————————————|
HackRF powered antenna support https://lists.osmocom.org/pipermail/osmocom-sdr/2015-May/000059.html
SAW Filter/LAN:
https://en.wikipedia.org/wiki/Surface_acoustic_wave
“SAW filters are now used in mobile telephones, and provide technical advantages
in performance, cost, and size over other filter technologies such as quartz crystals
(based on bulk waves), LC filters, and waveguide filters specifically at frequencies
below 1.5-2.5 GHz depending on the RF power needed to be filtered. Complementing
technology to SAW for frequencies above 1.5-2.5 GHz is based on thin-film bulk acoustic
resonators (TFBAR, or FBAR).”
Generate Image:
WXtoImg
“WXtoImg is a fully automated APT and WEFAX weather satellite (wxsat) decoder.
The software supports recording, decoding, editing, and viewing on all versions of
Windows, Linux, and macOS. WXtoImg supports real-time decoding, map overlays,
advanced colour enhancements, 3-D images, animations, multi-pass images, projection
transformation (e.g. Mercator), text overlays, automated web page creation,
temperature display, GPS interfacing, wide-area composite image creation and computer
control for many weather satellite receivers.”
– taken from the WXtoImg website.
Visit the WXtoImg website for more information
Downloads
Windows (pre-configured) – Recommended
Windows (original)
Linux (32-Bit) Debian Package
Linux (32-Bit) RPM Package
Linux (64-Bit) TAR.GZ
macOS X (32-Bit)
Installation Notes
When starting WXtoImg for the first time after using the original installation,
please go to Options > Active APT Satellites and uncheck NOAA 17 from the list of
active satellites because this satellite has reached EOL and has been shut down.
Next, on the same window, it is necessary to change the frequencies of NOAA 18 to
137.9125 MHz and of NOAA 19 to 137.1000 MHz. Then immediately update the kepler
data by clicking File > Update Keplers.
Not deactivating NOAA 17 and using out-of-date
kepler data may cause WXtoImg to crash.
Windows
For Windows users we recommend using our custom pre-configured installation of WXtoImg
with NOAA 17 already deactivated and satellite frequencies correctly set.
Linux 64-Bit
To install the 64-Bit version of WXtoImg on Linux use the following command:
gunzip < wxtoimg-linux64-2.10.11-1.tar.gz | sudo sh -c “(cd /; tar -xvf -)”
To start the software with a graphical user interface type xwxtoimg.
References with great websites:
Receiving NOAA weather satellite images with a RTL dongle
and a Turnstile crossed dipole automatically.
Radio Amateur web site
ZR6AIC
http://zr6aic.blogspot.com/2017/03/receiving-noaa-weather-satellite-images.html
Hardware Overview:
Raspberry PI and power supply
RTL dongle with USB cable and MCX connector adaptor.
RG58 Coaxial cable with connectors or better cable. Max 4m
Turnstile crossed dipole Antenna.
includes Apache2 web server setup
Automated Weather Satellite Ground Station
Project Lab
Includes AWS hosting setup