National Weather Service United States Department of Commerce

Heat Continues for the East and South-Central U.S.; Strong to Severe Storms Across the Mid-Atlantic and Northeast

The extremely dangerous heat wave continues across the East Coast and much of the South-Central U.S. today. Record high temperatures are expected for some areas especially across the Mid-Atlantic where extreme heat risk conditions reside. There is a Slight Risk (level 2 of 5) of severe thunderstorms today for the northern Mid-Atlantic into portions of southern New England. Read More >


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