The link from the handheld satellite phone to the satellite has C/N = -0.3 dB. ThisC/N ratio is much too low for the demodulator at the earth station to recover the signal, soadditional antenna gain must be included in the link. The minimum required C/N is 10 dB, sowe must increase antenna gain at the satellite by 10.3 dB. We cannot increase the gain of thesatellite telephone because it needs an omni-directional antenna, which has a gain of 0 dB ydefinition. The satellite antenna that services the whole coverage zone has G = 3.6 dB on axis,so we must provide an antenna with G = 13.9 dB ( = 24.4 as a ratio) to meet the uplink C/Nobjective of 10 dB. The beamwidth of an antenna with G = 13.9 dB is given by
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