1.模拟通讯:
在模拟通信中,借助模拟信号在发送器和接收器之间传输数据。任何类型的数据都以模拟信号传输。任何数据都首先转换为电子形式,然后再通过通信通道传递。模拟通信使用一个连续的信号,该信号的幅度,相位或某些其他属性随时间的变化与变量的大小成比例。
下图说明了模拟通信系统:
2.数字通讯:
在数字通信中,在源和目的地之间使用数字信号而不是模拟信号进行通信。它们的数字信号由离散值而不是连续值组成。在数字通信中,数据的物理传输以数字比特流的形式发生,即在点对点或点对多点传输介质上为0或1。在数字通信中,数字传输数据可以分解为分组,作为离散消息,这在模拟通信中是不允许的。
下图说明了数字通信系统:
模拟通信与数字通信之间的区别:
S .No. | ANALOG COMMUNICATION | DIGITAL COMMUNICATION |
---|---|---|
01. | In analog communication analog signal is used for information transmission. | In digital communication digital signal is used for information transmission. |
02. | Analog communication uses analog signal whose amplitude varies continuously with time from 0 to 100. | Digital communication uses digital signal whose amplitude is of two levels either Low i.e., 0 or either High i.e., 1. |
03. | It gets affected by noise highly during transmission through communication channel. | It gets affected by noise less during transmission through communication channel. |
04. | In analog communication only limited number of channels can be broadcasted simultaneously. | It can broadcast large number of channels simultaneously. |
05. | In analog communication error Probability is high. | In digital communication error Probability is low. |
06. | In analog communication noise immunity is poor. | In digital communication noise immunity is good. |
07. | In analog communication coding is not possible. | In digital communication coding is possible. Different coding techniques can be used to detect and correct errors. |
08. | Separating out noise and signal in analog communication is not possible. | Separating out noise and signal in digital communication is possible. |
09. | Analog communication system is having complex hardware and less flexible. | Digital communication system is having less complex hardware and more flexible. |
10. | In analog communication for multiplexing
Frequency Division Multiplexing (FDM) is used.
|
In Digital communication for multiplexing
Time Division Multiplexing (TDM) is used.
|
11. | Analog communication system is low cost. | Digital communication system is high cost. |
12. | It requires low bandwidth. | It requires high bandwidth. |
13. | Power consumption is high. | Power consumption is low. |
14. | It is less portable. | Portability is high. |
15. | No privacy or privacy is less so not highly secured. | Privacy is high so it is highly secured. |
16. | Not assures an accurate data transmission. | It assures a more accurate data transmission. |
17. | Synchronization problem. | Synchronization problem is easier. |