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当今世界通信技术正在日新月异地发展,各种复杂的通信系统不断问世,这些新型的通信系统是根据这样几种原则开发的:(1)更高效率的信息传输;(2)避免周围环境干扰的影响;(3)确保外来有用信息的接收和避免第三方有意干扰信号的影响,等等。扩频通信技术是近几年发展迅速的一种方案,它给用户带来了更多的功能和更优的性能。简单说来,扩频技术的概念可以是通过附加信号方式将通常信号占据的基带带宽扩展成很宽的发射带宽,也可以是将射频信号的频谱扩展,或两者结合起来使用。无论哪一种方式,都能使传输频带大大加宽,从而提高了抗干扰和抗堵塞的能力,同时也避免了普通通信系统中由于多径信号抵消带来的衰落。这种技术已在新型军用无线电设备中广泛采用。跳频无线电系统是扩频通信技术的一种具
Today’s communications technologies in the world are evolving rapidly with the advent of complex communications systems based on several principles: (1) more efficient transmission of information; (2) protection of the environment from interference (3) to ensure the reception of useful information from outside and to avoid the intentional interference of signals by third parties, and so on. Spread spectrum communication technology is a rapid development in recent years, a program that gives users more features and better performance. In simple terms, the concept of spread spectrum technology can be extended by the additional signal usually baseband signal bandwidth occupied by a wide bandwidth, it can also be the spread spectrum of radio frequency signals, or a combination of both. Either way, the transmission band can be greatly broadened, thereby improving the anti-jamming and anti-jamming capabilities and avoiding the fading caused by multipath signal cancellation in normal communication systems. This technique is widely used in new military radio equipment. Frequency hopping radio system is a kind of spread spectrum communication technology