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From: benjamin@ee.tut.fi (Gr|nlund Pentti)
Newsgroups: comp.dcom.lans
Subject: Re: microwave blockage
Message-ID: <1991Jun12.063529.21345@cc.tut.fi>
Date: 12 Jun 91 06:35:29 GMT
Sender: news@cc.tut.fi (USENET News System)
Organization: Tampere University of Technology
Lines: 11
Originator: benjamin@uikku.ee.tut.fi


Someone asked here about microwave ethernet blockage by trees etc.

Radio link performance in free space is determined by frequency, distance,
transmitter and receiver antenna gains, feed line loss in both ends and
receiver sensitivity. You can find the equations in every radio link, radar,
space communications and amateur microwave handbook.

In real life there are a lot of additional loss factors caused by terrain
formation and all kinds of obstructions. The attenuation caused by wet trees
(especially those with BIIIG leaves) can be tens of decibels and this can
contribute to loss of signal in marginal installations.