ITM 301 Lecture Notes - Lecture 8: Frequency-Hopping Spread Spectrum, Bluesnarfing, Bluejacking
15 Dec 2017
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Document Summary
Itm 301 characteristics of wireless transmission. Wireless networks (wlans: networks that transmit signals through the air via radio frequency (rf) waves. Wired and wireless signals share many similarities: use of the same layer 3 and higher protocols. The nature of the atmosphere makes wireless transmission different from wired transmission. Los (line-of-sight: signal travels in straight line directly from transmitter to receiver. When obstacles are in a signal"s way, the signal may: pass through them, be absorbed into them, be subject to three phenomena. Moving away from transmission antenna: correcting signal attenuation. Amplify or repeat the signal from a closer broadcast point called a range extender. Noise: also known as emi, more vulnerable to noise. No wireless conduit, shielding: signal-to-noise ratio (snr) = proportion of noise to the strength of a signal. 2. 4-ghz band (older: frequency range: 2. 4 2. 4835 ghz, 11 unlicensed communications channels, susceptible to interference.
