Wi Lan Inc EB02 Benutzerhandbuch

Antenna Basics

APR 2001 Rev 03

121

Some factors you should consider when installing antennas into your wireless system are listed below.

Maximizing the 
AWE 120-58’s 
Capabilities

• Minimize obstructions in the radio path
• Line Of Sight (LOS) is crucial for reliability
• Ensure that equipment is installed correctly
• Ensure proper grounding, testing, and alignment of antennas
• Install in environmental conditions that are suitable for the AWE unit
• Select proper antennas and cable for the application
• Ensure sufficient gain for the intended application

Safety

• Proper grounding of antenna apparatus in accordance with respective 

Electrical Code(s) is crucial

• Wi-LAN recommends using a surge arrestor where the antenna cable 

enters the building

• All installations should be completed by a qualified and competent RF 

technicial

EIRP

• Effective Isotropically Radiated Power (EIRP)
• EIRP is the amount of power that is transmitted to the air from the 

antenna

• EIRP levels depend on the power of the radio transmitter, the gain of the 

antenna, and the losses incurred in the antenna cable

• EIRP must not exceed 4 W or 36 dBm in Canada and the United States for 

point-to-multipoint applications.
Note: EIRP = Power out of unit – Power lost in cable + Gain in power from 
Antenna

Fade Margin

See 

LOS

• Line of Sight (LOS)
• LOS is a football shaped pattern known as the Fresnel Zone, which must 

be kept clear of obstructions. See 

, page 115 for more 

information

• Visual line of sight must be achieved. When standing at the antenna 

position, you must be able to see the remote antenna