Appendix D Wireless LANs
P-660HN-F1A User’s Guide
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Antenna Overview
An antenna couples RF signals onto air. A transmitter within a wireless device
sends an RF signal to the antenna, which propagates the signal through the air.
The antenna also operates in reverse by capturing RF signals from the air.
Positioning the antennas properly increases the range and coverage area of a
wireless LAN.
Antenna Characteristics
Frequency
An antenna in the frequency of 2.4GHz (IEEE 802.11b and IEEE 802.11g) or 5GHz
(IEEE 802.11a) is needed to communicate efficiently in a wireless LAN
Radiation Pattern
A radiation pattern is a diagram that allows you to visualize the shape of the
antenna’s coverage area.
Antenna Gain
Antenna gain, measured in dB (decibel), is the increase in coverage within the RF
beam width. Higher antenna gain improves the range of the signal for better
communications.
For an indoor site, each 1 dB increase in antenna gain results in a range increase
of approximately 2.5%. For an unobstructed outdoor site, each 1dB increase in
gain results in a range increase of approximately 5%. Actual results may vary
depending on the network environment.
Antenna gain is sometimes specified in dBi, which is how much the antenna
increases the signal power compared to using an isotropic antenna. An isotropic
antenna is a theoretical perfect antenna that sends out radio signals equally well
in all directions. dBi represents the true gain that the antenna provides.
Types of Antennas for WLAN
There are two types of antennas used for wireless LAN applications.
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Страница 10: ...Contents Overview P 660HN F1A User s Guide 10...
Страница 20: ...Table of Contents P 660HN F1A User s Guide 20...
Страница 21: ...21 PART I User s Guide...
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Страница 36: ...Chapter 2 Introducing the Web Configurator P 660HN F1A User s Guide 36...
Страница 44: ...Chapter 3 Status Screens P 660HN F1A User s Guide 44...
Страница 77: ...Chapter 4 Tutorials P 660HN F1A User s Guide 77 2 Leave the other settings as their defaults and click Apply...
Страница 84: ...Chapter 4 Tutorials P 660HN F1A User s Guide 84 Physical Port 1 3 exclude port 4 3 Click Apply...
Страница 88: ...Chapter 4 Tutorials P 660HN F1A User s Guide 88...
Страница 103: ...103 PART II Technical Reference...
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Страница 142: ...Chapter 7 LAN Setup P 660HN F1A User s Guide 142...
Страница 188: ...Chapter 9 Network Address Translation NAT P 660HN F1A User s Guide 188...
Страница 210: ...Chapter 10 Firewalls P 660HN F1A User s Guide 210...
Страница 236: ...Chapter 13 Certificates P 660HN F1A User s Guide 236...
Страница 240: ...Chapter 14 Static Route P 660HN F1A User s Guide 240...
Страница 256: ...Chapter 16 Quality of Service QoS P 660HN F1A User s Guide 256 Figure 111 QoS Class Example Boss 2...
Страница 276: ...Chapter 17 Dynamic DNS Setup P 660HN F1A User s Guide 276...
Страница 288: ...Chapter 18 Remote Management P 660HN F1A User s Guide 288...
Страница 344: ...Chapter 24 Troubleshooting P 660HN F1A User s Guide 344...
Страница 376: ...Appendix A Setting up Your Computer s IP Address P 660HN F1A User s Guide 376...
Страница 386: ...Appendix B Pop up Windows JavaScripts and Java Permissions P 660HN F1A User s Guide 386...
Страница 396: ...Appendix C IP Addresses and Subnetting P 660HN F1A User s Guide 396...
Страница 420: ...Appendix F Legal Information P 660HN F1A User s Guide 420...
Страница 430: ...Index P 660HN F1A User s Guide 430...