1 Computer Maintenance Mobile Devices: How they Operate Copyright © Texas Education Agency, All rights reserved.

Course Objectives Define and identify what constitutes a mobile device Demonstrate a working knowledge of mobile device operation Understand and explain how mobile devices communicate Copyright © Texas Education Agency, All rights reserved.2

Mobile Devices Mobile device: a small, hand-held computing device that typically weighs less than 2 pounds Copyright © Texas Education Agency, All rights reserved.3

Types of Mobile Devices Cell phones Smart phones Personal data assistants Tablet (more recently) Copyright © Texas Education Agency, All rights reserved.4

Mobile Devices Devices contain an operating system that allows them to run smaller applications called apps. Wireless connectivity is built into the device Wi-Fi Bluetooth Cellular Copyright © Texas Education Agency, All rights reserved.5

Mobile Device Interface Touch: Device interaction by touch can happen in many different ways: Touchscreen Stylus Mechanical keyboard & finger track pad/ball Copyright © Texas Education Agency, All rights reserved.6

Mobile Device Interface Touchscreen: Screen of the device contains layers with the LCD being on the bottom and the subsequent layers above house the touch sensors Two most widely used systems in mobile devices: Resistive and Capacitive Touch The screen is comprised of a large grid that signals the coordinates of the user’s input Copyright © Texas Education Agency, All rights reserved.7

Mobile Device Interface Resistive Touch: Two thin layers where one is electrically charged and the other senses the charge when the two are pressed together This is an older version of the touchscreen technology. Pressing firmly on the screen and using a stylus were the two most common means of using this technology Copyright © Texas Education Agency, All rights reserved.8

Mobile Device Interface Capacitive Touch: An insulator (glass) is coated with a grid of conductors that emit an electrostatic field that when touched allows the grid to locate where the field is being disrupted This is the current standard for touchscreen interfaces (smartphones, tablets, and other current mobile devices). Doesn’t require firm presses—merely a light touch Requires touch with skin (conductive) to function Copyright © Texas Education Agency, All rights reserved.9

Operating a Mobile Device Device Operation (Smartphone): Power button Turns the device on/off Home button – Usually located on a central part of the device Turns the screen on Exits an application May be a Back button Copyright © Texas Education Agency, All rights reserved.10

Operating a Mobile Device Device Operation (Smartphone) Cont’d: Back button (may also be the home button) Exits an application / Reverts to a previous screen Track pad – Some devices have this option also located in a central part of the device. Utilized to navigate on devices without a touchscreen Copyright © Texas Education Agency, All rights reserved.11

Mobile Devices – How They Communicate Mobile devices use three means of wireless communication: Wi-Fi, cellular, and Bluetooth Wi-Fi is used for small coverage areas Residential Businesses Cellular is used for large geographical areas Deployed by large telecom companies Bluetooth is for the smallest coverage areas Often utilized as an accessory device alongside mobile devices (ex. Bluetooth headset) Copyright © Texas Education Agency, All rights reserved.12

Mobile Devices – Wi-Fi Wi-Fi: Wireless technology that allows electronic devices to exchange data Wi-Fi (a.k.a. WLAN) was developed in the mid to late 1990s Developed by the technology that allows devices to transmit and receive data wirelessly through radio frequencies Requires an Internet source to function as a router (hub) and offers Internet connectivity to wireless devices Utilizes a standard that can connect with almost all mobile wireless devices Copyright © Texas Education Agency, All rights reserved.13

Mobile Devices – Wi-FI The different speeds of Wi-Fi b - Single Band Late 90s technology – 2.4 Ghz - 11 Mbits/s g – Dual Band Unified b/g 2003 standard – 2.4 Ghz – 54 Mbits/s n – Dual Band 2009 amendment – 2.4 & 5 Ghz – 54 to 600 Mbits/s ac – Fifth Generation of Wi-Fi – An emerging standard 5 Ghz – At least 1 gigabit per second Copyright © Texas Education Agency, All rights reserved.14

Mobile Devices – Wi-Fi Wi-Fi Security Wired Equivalent Privacy (WEP): Initial form of Wi-Fi security; introduced in 1999 and outdated by 2003 due to security concerns (least secure) Wi-Fi Protected Access (WPA): 2003 security implementation designed to make wireless networks more secure Wi-Fi Protected Access 2 (WPA2): Current security standard that employs a 256 bit encryption (most secure) Copyright © Texas Education Agency, All rights reserved.15

Mobile Devices – Wi-FI Wi-Fi Security: Connecting to the network Select network name Identify security type Mobile device should auto detect the security type Enter password Join Copyright © Texas Education Agency, All rights reserved.16

Mobile Devices – Cellular Cellular wireless: Wireless connectivity via cellular radio towers that are deployed across an extensive geographic area Providers utilize different technologies that can allow devices to work with one provider and not another Current cellular technologies are CDMA and GSM and LTE Cellular wireless speeds are increasing rapidly due to the benefits of the newest technology, LTE Copyright © Texas Education Agency, All rights reserved.17

Mobile Devices – Cellular Cellular wireless cont’d: Broadcast from the 450 Mhz frequency up to the 21 MHz frequency FCC oversees who owns what frequencies a cellular provider may utilize Lower frequencies allow a cellular radio tower a greater radius of range Lower frequencies also improve reception in buildings Copyright © Texas Education Agency, All rights reserved.18

Mobile Devices – Cellular Cellular wireless types: Code Division Multiple Access (CDMA): Aging 3G standard for wireless devices used for data and voice and is the dominant technology in the U.S. Global Systems for Mobile Communications (GSM): Newer 3G to 3.5G wireless technology; is the dominant technology utilized worldwide Copyright © Texas Education Agency, All rights reserved.19

Mobile Devices – Cellular Cellular wireless types cont’d: Long Term Evolution (LTE): 4G or 4 th generation of cellular wireless technology The next evolution of GSM; is being widely adopted Speeds currently are 2-10 times faster than 3G technology Copyright © Texas Education Agency, All rights reserved.20

Mobile Devices – Bluetooth Bluetooth: Wireless standard for exchanging data over short distances in the Mhz range Developed in 1994 as an alternative to data cables Must be paired with a compatible device to function Is used for data sharing and voice communications Uses low power (benefit) Examples of devices a mobile device can pair with: Smartphone, PDA, headset, printer, keyboard, and PC Copyright © Texas Education Agency, All rights reserved.21

Independent / Group Work Group Get into your groups Pick a class of mobile device (Smartphone / PDA / Tablet) Research where that device is heading with advancements in technology and the role that wireless communication is going to play in the functionality of that mobile device Once finished, your group will present your finding to the class Take detailed notes on each group’s research as it is being presented Individual Pick a wireless technology (Wi-Fi / cellular / Bluetooth) Research and list some benefits of the technology over other wireless technologies as well as some of its potential limitations Copyright © Texas Education Agency, All rights reserved.22

Exam Preparation An exam will be given over the material covered in the presentation Make sure to review your class notes and these slides Questions will be multiple choice and true/false Copyright © Texas Education Agency, All rights reserved.23