This question appears in Mumbai University > Satellite Communication and Network subject

Marks: 3 M

Year: May 2012

Sun Transmit Outage

• At certain times during equinoxes the satellite is in transit between the earth and the sun such that the sun comes within the beam width of the earth station antenna.
• When this happens the sun appears as extremely noisy source, which completely blanks out the signal from the satellite. This effect is called as sun transit outage.
• Sun transit outage lasts for short periods each day for about 6 days around the equinoxes. The occurrence and duration of the outage depends on the latitude of the earth station, a maximum outage time of 10 min being typical.
• The receiving earth station can do nothing but wait for the sun to move out of the beam width.
• This outage proves very costly to the domestic users because it occurs in day time and the receiving station has to find alternate channels for communication.