National Weather Service United States Department of Commerce

Severe Weather and Flooding Threats

A slow moving storm system continues to advance to the east bringing a severe weather and flash flooding threat from the Midwest to the central Gulf Coast. A Pacific storm system is expected to produce severe thunderstorms beginning late Thursday afternoon in the Northwest and Northern Rockies. 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