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Space environment above Quasi-equatorial ground has an advantage of relative quietness and friendliness. It is preferred to deploy satellites of demanding stability and longer lifespan. For these satellites, the communication via VHF between ground stations and satellites has become one of the difficulties when it comes to the satellite engineering. To make a quantitative assessment, the satellite VHF coverage of ground stations are carried out for two typical orbits, of which the altitude are roughly 500km and 550km,and the inclination is 2.5 deg. Ground stations for VHF communication include the 88 stations, which are distributed along the belt with latitude less than +/-30deg. The cutoff angles for VHF communication are 10 deg. Two antenna for communication are fixed in the satellite body along +Z axis and –Z axis respectively, and the half beam angle of the boresight is 90 deg. Simulations of satellites based VHF coverage of 88 ground stations are carried out. During case 1, satellite orbit altitude is assumed to be 500km,and inclination is 2.5 deg. For case 2, satellite orbit altitude is assumed to be 550km,and inclination is 2.5 deg. Satellite-based VHF coverages of 88 ground stations are 63.3% for case 1,and 66.5% for case 2. For case 1, yearly VHF communication opportunities are 34594 times. Average duration is 576 seconds. Daily VHF communication opportunities are 95 times. Daily available communication interval is 912 minutes. The unavailable time interval is 28.2 minutes. For case 2, yearly VHF communication opportunities are 29161 times. Average duration is 718 seconds. Daily VHF communication opportunities are 80 times. Daily available communication interval is 957 minutes. The unavailable time interval is 26.4 minutes. Case 1 is preferred if satellite engineering demands more quiet space environment. Case 2 is preferred if satellite engineering demands longer lifespan and better coverage. It is suggested that case 2 be a good choice for space science mission devoted to observe astronomical events in remote space.
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