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NOAAPORT Signal Characteristics

NOTE: The information on this page is subject to change. Use at your own risk. Check the 'What's new' page for change announcements.

The NOAAPORT signal is actually four signals. One for each of four NOAAPORT data streams. Each Channel carries a different data stream and all channels use the same basic data communications protocol suite. A Satellite Coverage Map, for the GE Americom GE-4 Transponder 15C, is available in PDF format.

Modulation for all channels uses differential quadrature phase-shift keying (QPSK). Demodulation for all channels uses the spectral inversion and V.35 descrambling functions of the EFData SDR54A.

NOAAPORT Link Budget Parameters and Characteristics Chart (xls format)

The uplink modulators and demodulators implement a concatenated code that incorporates a convolutional encoder/decoder, a data interleaver/de-interleaver, and a Reed Solomon encoder/decoder. The specific demodulators that will be used at the receive sites are the EFData SDR54A with the Reed Solomon concatenated code.

Data Stream and Decoder Characteristics
Differential EncodingON
Convential Code Constraint Lengthk=7
Convolutional Code Rate3/4
Interleave Depth16
Reed Solomon Code (N, K, t)(225, 205,10) per IESS-308, Appendix G
Reed Solomon Symbol Size8 bits

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