If this power is uniformly distributed over the area illuminated on the earth's surface what is the power per meter squared at the receiving antennas? c) Today the typical diameter of the receiving dish on people's homes is 46 cm. What is the diameter of the area that this antenna can illuminate on the earth using a 12GHz down link carrier frequency? b) The downlink transponders (consisting of a receiver that detects the 14GHz uplink signal, amplifies it, frequency shifts it using a mixer to a new 12 GHz downlink carrier frequency and then amplifies it more and drives a power amplifier/transmitter that feeds the antenna) send out the signal with a power of 120W (a little more than an old incandescent light bulb!). This allows fixed antennas without tracking capability to receive the signals, significantly lowering system cost a) One of the DirectTV satellites named T10 has a downlink antenna that is 1.75 meters (69 inches) in diameter. At this distance their orbital period is the same at the earths rotational period so they appear to be motionless when viewed from the earths surface. They orbit the Earth at a distance of 37,000 km (23,000 miles) above the equator. Today they typically use microwave frequencies in the Ku Band.
#Directv channel satellite transponder list tv
Transcribed image text: 6) Satellite Communications transponders 14 GHz uplink 2GHE downlink TV STUDIO Satellite TV is provided by high frequency links as shown above by companies such as DirecTV and the Dish Network in North America.