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一天夜晚,屋外风声大作,雷电交加,可是电视观众却安然地围坐在一起,观看色彩鲜艳、图象清晰、音色优美的精彩节目。人们也许感到奇怪:无线电信号受到自然界和人工的干扰,这是一个常识。在雷电交加的情况下还能看电视吗?当然可以,不过不是在现在,而是在未来的一天。前不久,在柏林举行的一次世界科学家座谈会上,法国和西德的科学家宣布,他们正在联合研究一项代号为“交响乐”的抗干扰工程。实际上,这是一个特殊的通信卫星系统。现在这套试验性的卫星系统已开始服务于教育、科学等事业。将来,这个卫星系统的两颗卫星,还将分别向法国和西德的电视接收机定向发送信号,电视观众只需在自己家里安装一个抛物面天线和一个频率变换器,就可以直接收看卫星转播的节目。那时,不论是居住在法国南部美丽的科西嘉岛上的观众,还是住在西柏林繁华
One night, there was a windy day with lightning and thunder and lightning, but the TV audience sat around safely and watched colorful programs with vivid images and clear sound. People may wonder: radio signals are subject to natural and human interference, it is a common sense. Can you watch TV while thunderstruck? Sure, but not now, but in the days to come. Not long ago, at a world scientist symposium in Berlin, scientists from France and West Germany announced that they were jointly studying an anti-jamming project, code-named “Symphony.” In fact, this is a special communications satellite system. Now the experimental satellite system has begun to serve the education, science and other undertakings. In the future, the two satellites of the satellite system will also separately send signals to television receivers in France and West Germany, allowing television viewers to watch satellite transmissions directly by simply installing a parabolic antenna and a frequency translator in their own home program. At that time, both the audience living in the beautiful Corsican island in southern France lived in downtown Berlin,