HRPT Satellite Tracking and Capture
Weather satellite pictures are often broadcast as high-resolution picture transmissions (HRPTs), color high-resolution picture transmissions (CHRPTs) for Chinese weather satellite transmissions, or advanced high-resolution picture transmissions (AHRPTs) for EUMETSAT weather satellite transmissions. HRPT transmissions are available around the world and are available from both polar and geostationary weather satellites. The polar satellites rotate in orbits that allow each location on earth to be covered by the weather satellite twice per day while the geostationary satellites remain in one location at the equator taking weather images of the earth from that location over the equator. The sensor on weather satellites that picks up the data transmitted in HRPT is referred to as an Advanced Very High Resolution Radiometer (AVHRR).
The working frequency band for HRPT is L Band at 1.670–1.710 GHz and the modulation types are BPSK and QPSK. On NOAA KLM satellites the transmission power is 6.35 Watts, or 38.03 dBm. The METOP-A satellite broadcasts with a bandwidth of 4.5 MHz.
In order to receive HRPT transmissions, a high gain antenna is required, such as a small satellite dish, a helical antenna, or a crossed yagi. Basic reception equipment includes a parabolic dish antenna attached to an Azimuth-Elevation unit. The HRPT signal is further enhanced with a 1.7 GHz pre-amplifier. An HRPT receiver unit and a dish tracking controller are required to steer the Azimuth-Elevation unit controlling the parabolic dish.
These satellites can be received on L-Band that all transmit a HRPT Signal:
- NOAA15 (very weak)
- Meteor M2 (Weak, broken Antenna)
- Meteor M2-N2 (APT is non functional)
- MetOp A (only active in some Areas)
- MetOp B
- MetOp C
- FengYun 3B
Over at Tynet.eu he has what appears to be an excellent tutorial on building an complete HRPT receiving station. Complete with Hardware, Software, Antenna and Dish builds, etc. This is what I am going to follow and build a HRPT receiver for myself!
Here’s a video from him demonstrating his system: