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一、引言跳频就是传输信息的载波频率或它的频率组合的周期性变化。图1是一般跳频发射机和接收机的方框图。数据调制可以用多种形式,最初采用了二进制频移键控(F. S. K.)。当采用二进制F. S. K时,每一个编码比特(符号)用两个频率中的某一个来发射,其中一个频率代表逻辑“1”(mark),而另一个频率代表逻辑“0”(space),可能出现的频率对是伪随机码作周期变化的,每一变化形成一跳。
I. INTRODUCTION Frequency hopping is the periodic variation of the carrier frequency or its frequency combination that transmits information. Figure 1 is a block diagram of a typical frequency hopping transmitter and receiver. Data modulation can take many forms, initially using binary frequency shift keying (F. S. K.). When binary FSK is used, each coded bit (symbol) is transmitted with one of two frequencies, one of which represents a logical “1” mark and the other of which represents a logical “0” space, Possible frequency pairs are pseudo-random code cycle changes, each change to form a jump.