Digital Vs. Analog Signals

Digital vs. Analog Signals Think about how you communicate with other people on a daily basis. Do you call on your cell phone, text, or email? Have you ever used a landline to make a phone call? Now, think about how messages are actually sent and received. Messages are delivered by signals, which are wave pulses that can be transmitted and received. Digital vs. Analog Signals Although both digital and analog signals deliver messages, they have more differences than similarities. People send messages via signals everyday. Analog Signals signal: a wave pulse that Analog signals are made up of continuously streaming data. can be transmitted or Look at the picture of the clocks to the right. The top one you received probably already know is called a digital clock, but did you know the bottom one is called an analog clock? Why do you think that would be? Analog clocks provide continuous data (as shown by the constant movement of the second and minute hands) just like analog signals provide continuous data. Analog signals also have significant variation. Take a light wave, for example. In the visible light spectrum, you can see a full range of colors. There’s not just blue and green, but a multitude of other colors that fall between those two. Analog signals vary in frequency just as the waves carrying the information continuously vary. 1 Digital vs. Analog Signals Digital Signals Digital signals, on the other hand, are like a light switch. They have two distinct values that they can send, rather than an infinite set of values like in analog signals. A common digital signal is binary code, a language of just zeroes and ones that computers use to communicate. A one in binary turns on the signal, while zero turns off the signal. Like a light switch, digital signals have two values. Which type of signal is a more reliable way to encode and transmit information? The answer is digital. Can you think of why this is the case? If a message is disrupted, digitized signals are able to pick it up more easily at the exact point the message dropped. (The segmented nature of the digital signal allows this.) Analog signals, on the other hand, are continuous; if they are disrupted, they must be restarted at the very beginning of the message. This is why more modern technological devices tend to use digitized signals rather than analog ones. Digital signals send segments, while analog signals send continuous streams. 2 Digital vs. Analog Signals What Do You Know? Show what you have learned about digital and analog signals by completing the Venn diagram below. Sort the words and phrases from the word bank into the correct places. Afterward, add any additional words or phrases that will help you differentiate the two signal types. Digital Signals Analog Signals Word Bank Transmitted as pulse More reliable Less reliable Used by landline telephones Used by computers All electromagnetic waves Converted into binary code Continuous Intervals 3 Digital vs. Analog Signals Digital and Analog Signals at Home To help your child better understand the differences between digital and analog signals, go on a photo scavenger hunt of all the electronic devices around your house that send out a signal. Take pictures of each device. Next, sort the pictures of the devices into two groups – those that send out analog signals and those that send out digitized signals. If you have a modem in your home, make sure you stop there and discuss it. Modems convert the digital signals from the computer to analog signals that can then be sent out over the telephone line. Point out to your child the different cords running in and out of the modem. Ask which type of signal is at each point. Here are some questions to discuss with your child: 1. What is an analog signal? 2. What is a digital signal? 3. Which type of signal is more reliable? 4. How are digitized signals sent? 4 .

Load more