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Capturing a NOAA Satellite Image

Introducing NOAA Series Satellites

NOAA satellites are USAAAAAAA spacecraft. They are launched into polar solar-synchronous circular orbits about 850 km high.

NOAA-15 launched May 13, 1998 in the morning orbit

NOAA-18 launched on May 20, 2005 in the afternoon orbit

NOAA-19 launched February 6, 2009 in the afternoon orbit

A sun-synchronous orbit is an orbit in which a satellite passes over any point on the earth’s surface at approximately the same local solar time. To achieve such characteristics, the parameters of the orbit are selected so that the orbit precesses eastward by 360 degrees per year (approximately 1 degree per day), compensating for the Earth's rotation around the Sun.

The circulation period is about 101 minutes. The orbital inclination is 98 degrees, so the satellites have a good view of the polar regions. NOAA satellite manufacturer is Lockheed Martin Corporation, a type of TIROS-N satellite platform. The following measuring instruments are installed on board: High resolution radiometer AVHRR / 3 6 channels visible and near infrared;

HIRS / 3 infrared meter 20 channels of visible and IR ranges;

AMSU-A microwave probe 15 channels of an infrared range;

AMSU-B microwave probe 5 channels of an infrared range;

All these tools work in different parts of the infrared range and allow you to receive a large amount of information. NOAA satellites collect global data on cloud cover, surface conditions such as ice, snow and vegetation, atmospheric temperature, moisture distribution, aerosols and ozone. Also, satellites are equipped with special devices that facilitate the search and rescue of those in distress. This is part of the COSPAS-SARSAT system, which is designed to detect and locate emergency radar transmitters, emergency beacons with location and personal radio beacons operating at 121.5, 243 and 406.05 MHz.

Receiving images from NOAA satellites.

The following software is used to receive images from NOAA satellites: • SDR # for receiving a radio signal; • Orbitron for tracking satellites and taking into account the Doppler effect; • WXtoimg for decrypting images. Launch SDR # and select the type of radio: RTL-SDR connected via USB.

In the Radio section, set the switch to WFM mode and set the Bandwidth to 34000. Check that the “Shift” checkbox is unchecked.

Make sure the “Filter Audio” checkbox is unchecked.

Next, you need to increase the signal gain. To do this, click on the gear.

Move the slider so that the noise level rises by about 10dB.

The signal from the NOAA series satellite looks something like this.

In the Tracking DDE Client section, when Orbitron is connected correctly, information about the monitored satellites will appear.

  Launch Orbitron and update TLE first. Click on the tool button.

Press the zipper button to update the TLE.

Then select the weather satellite information file. Click the Download TLE button.

Download the weather.txt list

In the side list on the right, only weather satellites will appear. Choose Meteor-M2, NOAA15, NOAA18, NOAA19.

The selected satellites will be shown in the main program window.

Then go to the Calculation tab and click on the Calculation button.

The satellite will automatically calculate the flight time of the satellites. Go to the Rotor / Radio tab and make sure the tracking button is pressed.

In the window with the receive frequency (Dnlink / MHz) the following correct frequencies should be set:

NOAA 15 - 137.62 MHz;

NOAA 18 - 137.91 MHz;

NOAA 19 - 137.10 MHz.

Launch WXtoimg and verify that the signal source is configured correctly.

Select virtual CABLE Output.

Start recording.

To receive signals, turn on Auto Record.

Now, when any NOAA satellite appears higher than 10 degrees above the horizon, the recording of the transmitted image will automatically start.

Make sure that the signal level in the lower right corner is green, if not, increase the sound volume in SDR #.

With a good signal level from below, the resulting image will begin to appear line by line. Left in the visible range, and right in the infrared.

Wait for the transfer to end, and stop recording.

Switch to different information display modes and analyze the resulting images.

Compare the image with the image taken earlier, and see how the situation in the atmosphere has changed.

en/lesson05.txt · Last modified: 2020/03/25 16:03 (external edit)

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