论文部分内容阅读
广播电视用的广播卫星是通信卫星的一个分支,直播卫星是广播卫星的进一步发展.它的发射功率大至几百瓦,地面个体家用接收机通过直径一米左右的小型天线就可以直接收看电视. 卫星直播电视与地面电视广播相比,有如下两个优点:覆盖面积大,投资少.例如:一般电视台服务半径为40公里左右,覆盖面积约5000平方公里,如果用这样的电视台覆盖象我国这样大的幅员面积,要用
Radio and television broadcast satellite is a branch of communications satellite, direct broadcast satellite is a further development of broadcasting satellite.Its launch power up to hundreds of watts, the ground individual household receiver through the small antenna about a meter in diameter can watch TV directly Compared with terrestrial television broadcasting, satellite live television has the following two advantages: large coverage area and low investment, for example, the service radius of a general television station is about 40 km and the coverage area is about 5,000 square kilometers. If such a television station is used to cover China Such a large size, use