Session 16

Question 1

Electromagnetic Waves

Answer 1

like regular wave that oscillates with amplitude, wavelength, frequency, and phase

Question 2

Ideal for telecommunication

Answer 2

travels at light speed, needs no physical medium, propagates in all directions, delivers energy and power

Question 3

Frequency Modulation

Answer 3

same volume, different pitch

Question 4

Electromagnetic Waves: Application

Answer 4

entertainment (radio: AM, FM, Xm)
Communication (telephone, data communication, analog communication-walkie talkie)
Others (military rador, gps, medical- exray machine, home: microwave, security- full body scanner, speed gun, remote control, laser

Question 5

The Prime Spectrum

Answer 5

referring to the electromagnetic wave of 30 mhz to 3000 mhz
(right next to visible light, low end of larger electromagnetic spectrum)
virtues of prime spectrum, (easily penertrates walls, slow attenuation- travels long distance with low power, long battery life of slim design, same spectrum can be reused in multiple locations.

Question 6

Cellular standards

Answer 6

code division multiple access (CDMA)- verizon & sprints (5 out of 7 major carriers in the US)
Proprietary (owned by qualocomm)
device must be approved by carrier to join network

Question 7

Global system for mobile communication (GSM)

Answer 7

tmobile and at&T wireless
open network
plug and play device

Question 8

Cellular generations

Answer 8

1G” analog cellular networks for voice communication
2G” digital wireless networks, primarily for voice communication, limited data capability
3” high-speed; mobile; supports video and other rich media; always on a transmission for e-mail, web browsing, instant messaging
4” packet -switching, fastest, best mobility support

Question 9

Bluetooth

Answer 9

can link up to 8 devices in 10 meter area: PAN
low power requirements
replacing cables, remote, headset, earphone
transmission speed up to 25 mbps

Question 10

Typical Wi-Fi configuration

Answer 10

internet- router- access point

Question 11

wifi networks

Answer 11

strengths:
convenient: internet without cables
Inexpensive: comparable to cables and wires
compatible with many devices
speed: decent speed for regular internet use

Weakness:
security: omnidirectional signal means easy eavesdropping
limited range: <230 feet indoors
Congestion: much traffic on 2.4 and 5 GHz