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10 Cards in this Set
- Front
- Back
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Layer 1 and 2 Standards
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Like wired, wireless networks require layers _________ standards
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Wireless
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Companies are spending more money today on _____
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Wireless Propagation Problems
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- Electromagnetic Waves
- Omnidirectional Antennas - Dish Antennas - EMI – Electromagnetic Interference - shadow zones - inverse square law attenuation - absorption attenuation - multipath interference - phase Interference |
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wavelength
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Optical fiber transmission is measured in terms of wavelength
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frequency
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wireless measures in _____________
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Omnidirectional Antennas
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- signal spreads in all directions (no need to point at receiver)
- rapid attenuation (cannot send far) |
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Dish Antennas
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- signals focused on narrow range – line of sight
- must point at receiver - sent longer distances |
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EMI – Electromagnetic Interference
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- Signals sent on the same frequency (multiple
power sent from different devices at the same frequency) |
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shadow zones
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dead spots; places the signal cannot
penetrated because of obstacles in its path; grow worse as frequency increases (large amounts of data, more propagation issues) |
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Inverse Square Law Attenuation
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- over distances, the signal strength decreases inversely
(not linear drop in signal strength) - the further the distance, the greater the drop in signal strength |
