Path loss at 11GHz is 206.0 dB, including atmospheric loss. Answer: Each channel receiver has a noise bandwidth of 50 kHz or 47 dBHz. Calculate the C/N in clear air for an earth station receiving one BPSK voice signal. For Pt = 20 W and 500 channels, power per channels is 20 / 500 = 40 mW/ch. Answer: In FDMA, the output power of the transmitter is divided equally between the channels. Calculate the power transmitted by the satellite in one voice channel. Have antennas with a gain of 40 dB (1m diameter) and a receiver with Tsystem = 150K in clear air, and IF noise bandwidth 50 kHz.Ī. The earth stations used to receive the voice signals Each coded BPSK signal has a symbol rate of 50 kbps and requires a receiver with a noise bandwidth of 50 kHz per channel.
The transponder is used in FDMA mode to send 500 BPSK voice channels with half rate FEC coding. Path loss to this station is 206 dB, including clear air atmospheric loss. The satellite transmit antenna gain at 11 GHz is 30 dB towards a particular earth station. Which is operated at an output power level of 20W. Answer:Ī 14/11 GHz satellite communication link has a transponder with a bandwidth of 52 MHz Hence find the C/N in dB for the earth station. Calculate the noise power of the earth station in 36 MHz bandwidth. Answer: Calculate the path loss at 3.875GHz. Calculate the carrier power received by the earth station, in dBW. Hence satellite antenna gain towards earth station is 32.6 – 3 = 29.6 dB.ī. Calculate the gain of the satellite antenna in the direction of the receiving earth station. Assume the transponder carrier power is 10 W at the input port of the transmit antenna on the satellite.Ī.
(Assume antenna gain is 3 dB lower than in the center of the beam) Ignore your result for transponder output power in Question 1 above. The edge of the coverage zone of the satellite antenna. The receiving earth station has an antenna with a gain of 53 dB and a system noise temperature of 100 K and is located at 4-1 The antenna has a 6o E-W beamwidth and a 3o N-S beamwidth. On the satellite transmits at a frequency of 3875 MHz to an earth station at a distance of 39,000 km. The satellite in Question #1 above serves the 48 contiguous states of the US. Calculate the carrier power, in dBW and in watts, at the transponder output. Calculate the C/N ratio, in dB, in the transponder. Calculate the noise power at the transponder input, in dBW, in a bandwidth of 36 MHz. Answer: Uplink power budget gives Pr = Pt + Gt + Gr - Lp dBW = 20 + 54 + 26 – 199.6 = -99.6 dBWĬ. Calculate the power at the output port (sometimes called the output waveguide flange) of the satellite antenna, in dBW. The signal is then routed to a transponder with a noise temperature of 500 K, a bandwidth of 36 MHz, and a gain of 110 dB.Ī. The signal is received by a satellite at a distance of 37,500 km by an antenna with a gain of 26 dB. The transmitter output power is set to 100 W at a frequency of 6.100 GHz. A C-band earth station has an antenna with a transmit gain of 54 dB.
0 kommentar(er)
