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人们在长期的实践活动中创造了各种各样的计数方法,二进制是它们中的新秀,其计数方法只有两个符号,即“1”和“0”,它是“逢二进一、借一当二”,大家所熟悉的计算机采用的就是二进制。那么。它和通信又有什幺关系呢?这要从普通电话说起。模拟通信的取代者电话,是将声音的强弱变化,通过话筒转化为相应的电信号。这种电信号变化的规律跟声音变化相类似。换句话说,电信号完全模仿了声波变化的情况,是声波信号的“化身”,人们称这种信号叫模拟信号。传输模拟信号的通信方式,叫做模拟通信。现在的电话、收音机、电视,大都采用模拟通信方式。数字信号虽然也是由原始的声音、图像转化过来的电信号,不过它已
People have created a variety of counting methods in long-term practice. Binary is their rookie, counting only two symbols, “1” and “0,” which means “ Once Upon a Second ”, we are familiar with the computer is binary. Then What is the relationship between it and communications? This should start from the ordinary phone. Replacement of analog communications phone, is the strength of the sound changes, through the microphone into the corresponding electrical signals. This change of electrical signal with the sound of similar changes. In other words, the electrical signal completely imitates the change of the sound wave and is the “incarnation” of the sound wave signal. People call this signal an analog signal. Transmission of analog signal communication, called analog communication. Now the phone, radio, television, mostly using analog communications. Although the digital signal is also an electrical signal converted from the original sound and image, it has