Digital signal processing/Introduction

= What is DSP? = Digital signal processing (DSP) is a field that encompasses the analysis, modification, and synthesis of digital signals. Digital Signals are generally obtained by sampling continuous analog signals, which involves recording discrete values of the analog signals at regular intervals of time. This conversion is generally done by a device called the analog-to-digital converter (ADC).

As stated earlier, DSP allows us to analyze, modify, and synthesize signals. By performing these processes, we can convert unclear, obfuscated signals into clearer or more useful signals for a given purpose. For example, filtering can remove noise from a signal to produce a more reliable and meaningful signal. The biggest reason that digital signal processing is so widespread today is due to the huge number of digital computers being used in every facet of our technology, from your phone to the kiosk at an airport to smart lightbulbs. Each of these devices have to analyze, modify, or synthesize signals, and converting these signals into their digital representations is the easiest and most reliable method for processing signals.

= Why do we use it? = There are millions of applications of signal processing (both analog and digital), from wireless communications to audio and video to machine learning and beyond. Signal processing is without a doubt an incredibly important part of modern technology. That being said, why do we use digital signal processes in particular rather than their analog counterparts?

Advantages of DSP

 * Programmability: software digital signal processes can be quickly modified, in contrast to analog circuits, which must be physically rearranged
 * Versatility: Flexible and easy to upgrade
 * Stability: Less sensitive environmental changes such as electromagnetic interference
 * Cost: Digital computers are much more widespread and versatile than analog solutions, making them cheaper
 * Density: Digital information can be stored at much greater volumes in a more reliable manner than analog signals can.
 * Special applications like lossless compression
 * Easy to simulate

Disadvantages of DSP

 * Processing of signals usually involves more power consumption than analog circuits
 * The frequency range of the input and output signals are limited by the sampling rate
 * Information is lost in the sampling process through quantization and  aliasing

= Activity = In a word processor of your choice, write out answers to the following questions. For best results, answer all of the questions first before checking any of the answers:

Recall
 * 1) What are the three ways of processing digital signals mentioned in the introduction?
 * 2) In your own words, what are the disadvantages of digital signal processing?
 * 3) What is the name of the process through which an analog signal converted into a digital signal?
 * 4) What is the name of the device that usually performs the task outlined above?

Consider
 * 1) What do you think is the most valuable advantage of digital signal processing? Why?

Apply
 * 1) Imagine that you are in charge of designing a hardware device that needs to record temperature data from every room in a house. You plan to sell this device to homeowners so that they can have a detailed record of the temperature history of their house. Would you use an analog signal processor or a digital signal processor? Why?
 * 2) Think of a new question that forces you to think more about the lesson. If you think it may help others to think about it, place it in the 'Student questions' section below.

= Student questions =