National Weather Service United States Department of Commerce

Dangerous Heat Wave for the West; Severe Storms and Heavy Rain for Midwest and Plains

Severe storms and heavy rains are likely in the Upper Midwest and Plains through this evening. A long duration heat wave will build across the West through next week with excessive heat watches/warnings in effect from the Southwest to Northwest. TS Josephine is forecast to pass well north of Puerto Rico and the Virgin Islands while TS Kyle is forecast to move quickly away from land this weekend. Read More >

HRIT/EMWIN Reception


Sources for HRIT/EMWIN systems and components:


US Government auction of L-band frequency spectrum (1695 to 1710 MHz) adjacent to GOES-R HRIT/EMWIN transponder frequency is likely to adversely impact the reliability of HRIT/EMWIN signal reception in the US due to cell phone interference.

 

HRIT/EMWIN Downlink Characteristics (NESDIS-2)


Coding – BPSK

  • Convolutional rate ½ code with constraint length 7 concatenated with Reed Solomon (255,223) with Interleave = 4
  • Square Root Raised Cosine filtering using an Alpha factor of 0.3
  • The resulting “Necessary Bandwidth” for this signal will be 1.205 MHz

Modem Required: predicted C/No is in the range of 63-67 dB
Maximum Demodulator Required is -

  • Eb/No is 4.6 dB for a BER of 1x10-8 after decoding

Minimum Antenna System

  • At 5 degree elevation, the minimum antenna is 1.2 meter.
  • At 10 degrees or more elevation the minimum size is 1.0 meter
  • Using a LNA or LNB with a system noise temperature of about 200 K will provide a G/T of 1.0 dB/K or -0.3 dB/K respectively