Proxim CPN 65756B manual Overview Of The Outdoor Installation, Antenna Placement

Tsunami MP.11a Antenna Installation Guide

OVERVIEW OF THE OUTDOOR INSTALLATION

The outdoor installation of the link (point-to-point or point-to-multipoint) requires the following:

▪An antenna

▪A low-loss antenna cable (available in three lengths)

▪Antenna mast or wall bracket for the antenna

▪An adequate grounding system that meets the requirements described in “Grounding System.”

▪Waterproofing of all connections

Note: All outdoor cable connectors must be sealed with weatherproofing stretch tape to make the coax connectors permanently waterproof. See “Sealing the Cable Connectors” on page 29.

DANGER!	For your own safety, the antenna mast and the grounding system should only be installed by
	experienced installation professionals who are familiar with local building and safety codes and
	the national electrical codes.
	Read carefully the instructions described in “Grounding System” on page 16 and verify that your
	installation complies with the appropriate regulations and codes before installing the antenna.

Antenna Placement

To achieve maximum performance of your wireless outdoor link, the outdoor antenna must have clear line- of-sight to the antenna of the other Tsunami MP.11a unit. Although the MP.11a radio signal can work well without line-of-sight in urban environments, where the signal is transported by reflection instead of being direct, the best results are achieved in line-of-sight conditions.

Line-of-sight can be defined as:

▪No obstacles in the direct path between the antennas (antenna beam).

▪No obstacles within a defined zone around the antenna beam.

You should be aware that the shape of an antenna beam is not straight and narrow like a laser beam. The antenna beam, also referred to as Fresnel1 Zone, is rather “bulged” in the middle, such as, for example, a rugby ball.

The exact shape and width of the Fresnel Zone is determined by the path length and frequency of the radio signal. The width as distance from the direct antenna beam is approximately 6 m (21 ft) in the middle of the wireless link for a distance of 6.5 Km (4 mi) and a frequency of 5.8 GHz. This width also is the required clearance of the antenna beam from obstacles in its path, to avoid loss of radio signal.

1Pronounced as ‘Fray-Nell’

Chapter 1. Preparing for Installation	12
CPN 65756B	Issue Date: August 2003