Appendix E Wireless LANs
ZyWALL USG 300 User’s Guide
1059
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 30: ...Table of Contents ZyWALL USG 300 User s Guide 30 ...
Страница 31: ...31 PART I User s Guide ...
Страница 32: ...32 ...
Страница 38: ...Chapter 1 Introducing the ZyWALL ZyWALL USG 300 User s Guide 38 ...
Страница 46: ...Chapter 2 Features and Applications ZyWALL USG 300 User s Guide 46 ...
Страница 64: ...Chapter 3 Web Configurator ZyWALL USG 300 User s Guide 64 ...
Страница 74: ...Chapter 4 Installation Setup Wizard ZyWALL USG 300 User s Guide 74 ...
Страница 116: ...Chapter 6 Configuration Basics ZyWALL USG 300 User s Guide 116 ...
Страница 128: ...Chapter 7 Tutorials ZyWALL USG 300 User s Guide 128 Figure 73 Configuration Network Interface WLAN Add ...
Страница 184: ...Chapter 7 Tutorials ZyWALL USG 300 User s Guide 184 ...
Страница 221: ...Chapter 8 L2TP VPN Example ZyWALL USG 300 User s Guide 221 ...
Страница 222: ...Chapter 8 L2TP VPN Example ZyWALL USG 300 User s Guide 222 ...
Страница 223: ...223 PART II Technical Reference ...
Страница 224: ...224 ...
Страница 238: ...Chapter 9 Dashboard ZyWALL USG 300 User s Guide 238 ...
Страница 282: ...Chapter 10 Monitor ZyWALL USG 300 User s Guide 282 ...
Страница 303: ...Chapter 13 Interfaces ZyWALL USG 300 User s Guide 303 Figure 269 Configuration Network Interface Ethernet Edit ...
Страница 320: ...Chapter 13 Interfaces ZyWALL USG 300 User s Guide 320 Figure 275 Configuration Network Interface Cellular Add ...
Страница 330: ...Chapter 13 Interfaces ZyWALL USG 300 User s Guide 330 Figure 278 Configuration Network Interface WLAN Add No Security ...
Страница 345: ...Chapter 13 Interfaces ZyWALL USG 300 User s Guide 345 Figure 286 Configuration Network Interface VLAN Edit ...
Страница 355: ...Chapter 13 Interfaces ZyWALL USG 300 User s Guide 355 Figure 288 Configuration Network Interface Bridge Add ...
Страница 378: ...Chapter 14 Trunks ZyWALL USG 300 User s Guide 378 ...
Страница 394: ...Chapter 15 Policy and Static Routes ZyWALL USG 300 User s Guide 394 ...
Страница 408: ...Chapter 16 Routing Protocols ZyWALL USG 300 User s Guide 408 ...
Страница 428: ...Chapter 19 NAT ZyWALL USG 300 User s Guide 428 ...
Страница 433: ...Chapter 20 HTTP Redirect ZyWALL USG 300 User s Guide 433 ...
Страница 434: ...Chapter 20 HTTP Redirect ZyWALL USG 300 User s Guide 434 ...
Страница 456: ...Chapter 23 Authentication Policy ZyWALL USG 300 User s Guide 456 ...
Страница 474: ...Chapter 24 Firewall ZyWALL USG 300 User s Guide 474 ...
Страница 481: ...Chapter 25 IPSec VPN ZyWALL USG 300 User s Guide 481 Figure 355 Configuration VPN IPSec VPN VPN Connection Edit IKE ...
Страница 492: ...Chapter 25 IPSec VPN ZyWALL USG 300 User s Guide 492 Figure 358 Configuration VPN IPSec VPN VPN Gateway Edit ...
Страница 515: ...Chapter 25 IPSec VPN ZyWALL USG 300 User s Guide 515 ...
Страница 516: ...Chapter 25 IPSec VPN ZyWALL USG 300 User s Guide 516 ...
Страница 529: ...Chapter 26 SSL VPN ZyWALL USG 300 User s Guide 529 ...
Страница 530: ...Chapter 26 SSL VPN ZyWALL USG 300 User s Guide 530 ...
Страница 540: ...Chapter 27 SSL User Screens ZyWALL USG 300 User s Guide 540 ...
Страница 542: ...Chapter 28 SSL User Application Screens ZyWALL USG 300 User s Guide 542 ...
Страница 550: ...Chapter 29 SSL User File Sharing ZyWALL USG 300 User s Guide 550 ...
Страница 635: ...Chapter 34 IDP ZyWALL USG 300 User s Guide 635 ...
Страница 636: ...Chapter 34 IDP ZyWALL USG 300 User s Guide 636 ...
Страница 646: ...Chapter 35 ADP ZyWALL USG 300 User s Guide 646 Figure 448 Profiles Protocol Anomaly ...
Страница 657: ...Chapter 35 ADP ZyWALL USG 300 User s Guide 657 ...
Страница 658: ...Chapter 35 ADP ZyWALL USG 300 User s Guide 658 ...
Страница 690: ...Chapter 37 Content Filter Reports ZyWALL USG 300 User s Guide 690 ...
Страница 708: ...Chapter 38 Anti Spam ZyWALL USG 300 User s Guide 708 ...
Страница 730: ...Chapter 39 Device HA ZyWALL USG 300 User s Guide 730 ...
Страница 746: ...Chapter 40 User Group ZyWALL USG 300 User s Guide 746 ...
Страница 752: ...Chapter 41 Addresses ZyWALL USG 300 User s Guide 752 ...
Страница 764: ...Chapter 43 Schedules ZyWALL USG 300 User s Guide 764 ...
Страница 780: ...Chapter 45 Authentication Method ZyWALL USG 300 User s Guide 780 ...
Страница 802: ...Chapter 46 Certificates ZyWALL USG 300 User s Guide 802 ...
Страница 814: ...Chapter 48 SSL Application ZyWALL USG 300 User s Guide 814 ...
Страница 820: ...Chapter 49 Endpoint Security ZyWALL USG 300 User s Guide 820 Figure 534 Configuration Object Endpoint Security Add ...
Страница 824: ...Chapter 49 Endpoint Security ZyWALL USG 300 User s Guide 824 ...
Страница 876: ...Chapter 50 System ZyWALL USG 300 User s Guide 876 ...
Страница 916: ...Chapter 54 Reboot ZyWALL USG 300 User s Guide 916 ...
Страница 918: ...Chapter 55 Shutdown ZyWALL USG 300 User s Guide 918 ...
Страница 938: ...Chapter 56 Troubleshooting ZyWALL USG 300 User s Guide 938 ...
Страница 946: ...Chapter 57 Product Specifications ZyWALL USG 300 User s Guide 946 ...
Страница 1118: ...Appendix F Open Software Announcements ZyWALL USG 300 User s Guide 1118 ...