Low Rate Picture Transmission (LRPT)

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Weather Satellite Modes: APT - LRPT - Meteosat WEFAX
Low Rate Picture Transmission (LRPT)
LRPTWaterfall.jpg
Frequencies 137 MHzMegaHertz (MHz) 10^6 Hz137,000,000 HzHertz (Hz), unit of frequency, defined as one cycle per second (1 Hz).
137,000 kHzKiloHertz (kHz) 10^3 Hz
,138 MHzMegaHertz (MHz) 10^6 Hz138,000,000 HzHertz (Hz), unit of frequency, defined as one cycle per second (1 Hz).
138,000 kHzKiloHertz (kHz) 10^3 Hz
137,000 kHzKiloHertz (kHz) 10^3 Hz
137 MHzMegaHertz (MHz) 10^6 Hz
138,000 kHzKiloHertz (kHz) 10^3 Hz
138 MHzMegaHertz (MHz) 10^6 Hz
Frequency Range 137 MHzMegaHertz (MHz) 10^6 Hz137,000,000 HzHertz (Hz), unit of frequency, defined as one cycle per second (1 Hz).
137,000 kHzKiloHertz (kHz) 10^3 Hz
- 138 MHzMegaHertz (MHz) 10^6 Hz138,000,000 HzHertz (Hz), unit of frequency, defined as one cycle per second (1 Hz).
138,000 kHzKiloHertz (kHz) 10^3 Hz
Mode RAW
Modulation QPSKQuadrature Phase-Shift Keying (2 bits per symbol)
ACF 0.5 msmilliseconds (.001 of a second)
Bandwidth 120 kHzKiloHertz (kHz) 10^3 Hz120,000 HzHertz (Hz), unit of frequency, defined as one cycle per second (1 Hz).
0.12 MHzMegaHertz (MHz) 10^6 Hz
120 kHzKiloHertz (kHz) 10^3 Hz
0.12 MHzMegaHertz (MHz) 10^6 Hz
120 kHzKiloHertz (kHz) 10^3 Hz
0.12 MHzMegaHertz (MHz) 10^6 Hz
Location Worldwide
Short Description The Low Rate Picture Transmission (LRPT) is a digital transmission system, commonly transmitted by METEOR-M satellites, used to deliver weather images and data.
I/Q Raw Recording Download file
Audio Sample

The Low Rate Picture Transmission (LRPT) is a digital transmission system, intended to deliver images and data from an orbital weather satellite directly to end users via a VHFVery High Frequency (30-300 MHz) radio signal. It is used aboard polar-orbiting, near-Earth weather satellite programs such as MetOp (LRPT permanently deactivated on MetOp-A due to interference with on HIRS) and NPOESS (replaced with JPSS), and is currently being used on METEOR-M satellites.


Characteristics[edit]

LRPT transmits at ~120 kHzKiloHertz (kHz) 10^3 Hz Bandwidth. The signal transmits using QPSKQuadrature Phase-Shift Keying (2 bits per symbol) at 80 kBdkilobaud, kilosymbols per second (ksym/s) (80,000 symbols per second) with a raw data rate of 160 kbpsKilobits per second (kbps). The datastream is processed using a Reed–Solomon error correction, then convolution encoded, interleaved, and padded with unique synchronization words. The result is a 62 kbpsKilobits per second (kbps) effective user data rate.

Each sensor on the satellite that uses LRPT to transmit its data is considered an application and provided a percentage of the transmission bandwidth in the form of a virtual channel. For example, the advanced very-high-resolution radiometer (AVHRR) imaging sensor is provided approximately 40 kbit/sKilobits per second (kbps) to transmit its three image channels, and the high-resolution infrared radiation sounder (HIRS) is provided approximately 2900 bit/sBits per second (bps).

Frequencies[edit]

  • Meteor-M N1 137.025 MHzMegaHertz (MHz) 10^6 Hz - 137.925 MHzMegaHertz (MHz) 10^6 Hz (Reported decommissioned)
  • Meteor-M N2 137.1 MHzMegaHertz (MHz) 10^6 Hz - 137.925 MHzMegaHertz (MHz) 10^6 Hz (Active)
  • Meteor-M N2-1 137.1 MHzMegaHertz (MHz) 10^6 Hz - 137.9125 MHzMegaHertz (MHz) 10^6 Hz (Planed launch ≥2016)
  • Meteor-M N2-2 137.1 MHzMegaHertz (MHz) 10^6 Hz - 137.9125 MHzMegaHertz (MHz) 10^6 Hz (Planed launch ≥2016)


Decoding Tutorials[edit]

Video Examples[edit]

Additional Links[edit]

Additional Images[edit]