Jabla, Jason Kim I. BSEE-22A1 (COMM 001) General Model of Communication System 1) Linear Model of Communication In linear model, communication is considered one way process where sender is the only one who sends message and receiver doesn't give feedback or response. The message signal is encoded and transmitted through channel in presence of noise. The sender is more prominent in linear model of communication. Example: Shannon-Weaver’s Model Originally developed by Shannon & Weaver in 1948, this model describes communication as a linear process. This model describes how a sender, or speaker, transmits a message to a receiver, or listener. More specifically, the sender is the source of the message. A message may consist of the sounds, words, or behaviors in a communication interaction. The message itself is transmitted through a channel, the pathway or route for communication, to a receiver, who is the target or recipient of the message. There may be obstacles in the communication process, or noise. Noise refers to any interference in the channel or distortion of the message. This is a fairly simple model in which a message is simply passed from sender to receiver. 2) Interactional Model of Communication Interaction models view the sender and the receiver as responsible for the effectiveness of the communication. One of the biggest differences between the action and interaction models is a heightened focus on feedback. Example: Osgood-Schramm Model Osgood-Schramm’s model of communication is known as a circular model because it indicates that messages can go in two directions. Hence, once a person decodes a message, then they can encode it and send a message back to the sender. They could continue encoding and decoding into a continuous cycle. This revised model indicates that: 1) communication is not linear, but circular; 2) communication is reciprocal and equal; 3) messages are based on interpretation; 4) communication involves encoding, decoding, and interpreting. The benefit of this model is that the model illustrates that feedback is cyclical. It also shows that communication is complex because it accounts for interpretation. This model also showcases the fact that we are active communicators, and we are active in interpreting the messages that we receive. 3) Transaction Model of Communication The transactional models differ from the interactional models in that the transactional models demonstrate that individuals are often acting as both the sender and receiver simultaneously. Basically, sending and receiving messages happen simultaneously. Example: Types of Electronic Communication Electronic communication takes many forms, each with its own applications, benefits and drawbacks. Though some electronic media may seem more familiar than others, each can instantly connect people whether they’re a few miles away or a few thousand miles away 1. Email Perhaps one of the most well known and most ubiquitous forms of electronic communication, email provides a channel for exchanging messages in much the same method as traditional mail. One user generates a message, addresses it to a recipient, sends it and, if one is warranted, waits for a reply. The asynchronous nature of email makes it ideal for users who do not want to become involved in, or do not have time for, a lengthy conversation. 2. Text and Instant Messages Text messaging uses cellular airwaves and protocols to deliver textual messages from one cellular phone to another or from one phone to a group of other phones. Text messaging is usually intended as near-instant communication and can be quicker than a phone call because the sender doesn't have to wait for the recipient to answer before delivering a message. Because text messaging is informal and easy, it's sometimes called chatting. Text messaging can also facilitate private discussions when there is a chance that a phone call could be overheard. Instant messaging is similar to text messaging but is carried over the Internet rather than over cell phone airwaves. 3. Websites Websites can take many forms and serve as a wide variety of electronic communication channels. In their most basic form, websites simply disseminate information to visitors who access and read information on the site. Other websites, like forums, facilitate communication by allowing you to post a public message and then check later to see if the message received any replies. Social media websites take a similar approach, allowing you to share aspects of your life and then read follow-up comments from friends. 4. Audio Electronic audio communication dates back to the 1876 invention of the telephone, a device that converts sounds into electrical impulses and sends them over copper wires to a remote unit that converts them back into sound. Today, though, audio traverses an array of electronic channels that includes radio, television, mobile phones and even Internet-connected electronic devices. 5. Video Like instant messaging, most video chatting is conducted over Internet protocols that stream images from one device to another. At times, nothing beats a face-to-face conversation. Video chats provide an immediacy to a conversation. Because a person's tone is often easier to read when you can see his face, businesses often use videoconferencing to aid in virtual meetings. 6. Blogging At present, blogging is the most preferable communication method. This is a type of online journaling, which can be updated daily, or many times a day. It covers all the information or a particular topic. By using such blogs, one can share, follow, or even post comments. This kind of communication is extremely suitable. This is the reason why people utilize blogs very often. Additionally, by using the internet, people can access, read & follow it worldwide. Analog Signal These type of electronic signals are time-varying Minimum and maximum values which is either positive or negative. It can be either periodic or non-periodic. Analog Signal works on continuous data. The accuracy of the analog signal is not high when compared to the digital signal. It helps you to measure natural or physical values. Analog signal output form is like Curve, Line, or Graph, so it may not be meaningful to all. Digital Signal Digital signal are continuous signals This type of electronic l signals can be processed and transmitted better compared to analog signal. Digital signals are versatile, so it is widely used. The accuracy of the digital signal is better than that of the analog signal. Analog Signal Digital Signal An analog signal is a continuous signal that Digital signals are time separated signals which represents physical measurements. are generated using digital modulation. It is denoted by sine waves It is denoted by square waves It uses a continuous range of values that help you to Digital signal uses discrete 0 and 1 to represent represent information. information. Temperature sensors, FM radio signals, Photocells, Computers, CDs, DVDs are some examples of Light sensor, Resistive touch screen are examples Digital signal. of Analog signals. The analog signal bandwidth is low The digital signal bandwidth is high. Analog signals are deteriorated by noise throughout Relatively a noise-immune system without transmission as well as write/read cycle. deterioration during the transmission process and write/read cycle. Analog hardware never offers flexible Digital hardware offers flexibility in implementation. implementation. It is suited for audio and video transmission. It is suited for Computing and digital electronics. Processing can be done in real-time and consumes It never gives a guarantee that digital signal lesser bandwidth compared to a digital signal. processing can be performed in real time. Analog instruments usually have s scale which is Digital instruments never cause any kind of cramped at lower end and gives considerable observational errors. observational errors. Analog signal doesn't offer any fixed range. Digital signal has a finite number, i.e., 0 and 1. The EM spectrum Electromagnetic waves are categorized according to their frequency f or, equivalently, according to their wavelength λ = c/f. Visible light has a wavelength range from ~400 nm to ~700 nm. Violet light has a wavelength of ~400 nm, and a frequency of ~7.5*1014 Hz. Red light has a wavelength of ~700 nm, and a frequency of ~4.3*1014 Hz. Visible light makes up just a small part of the full electromagnetic spectrum. Electromagnetic waves with shorter wavelengths and higher frequencies include ultraviolet light, X-rays, and gamma rays. Electromagnetic waves with longer wavelengths and lower frequencies include infrared light, microwaves, and radio and television waves. Type of Radiation Frequency Range (Hz) Wavelength Range gamma-rays 1020 - 1024 < 10-12 m x-rays 1017 - 1020 1 nm - 1 pm ultraviolet 1015 - 1017 400 nm - 1 nm 4 - 7.5*1014 750 nm - 400 nm 1*1014 - 4*1014 2.5 μm - 750 nm 1013 - 1014 25 μm - 2.5 μm microwaves 3*1011 - 1013 1 mm - 25 μm radio waves < 3*1011 > 1 mm visible near-infrared infrared