[MLB-WIRELESS] What's Cooking?

[Steve Wright]

auroria wrote:

>
>i was thinking the sus bit was the ramping up of power to deal with increased demand.  
>that doesn't make sence..  increase bandwidth not power.
>

A linear spread-spectrum transmitter output stage has a fixed power 
output, but it's perfectly feasible to mix in more SS streams (one RF 
carrier can carry a large number of SS 'CDMA' transmissions.)

However, you don't get the free lunch - the output power will be shared 
among all connections.

>  doesn't more power reduce 
>the width of a beam and make it harder to hit the target dish on the 'other side' ?
>

nope.  the only thing that causes a narrower beamwidth, is an antenna 
with a narrower beamwidth.  (think - narrower funnel, or more 
concentrated jet of water, as opposed to a shower rose which would be a 
sector antenna...)  Also "higher gain" does not mean "narrower beamwidth."

I heard a similar microwave burn story years ago, about a navy 
technician who climbed the tower but forgot to lock the ships' radar 
out.  Now these radars are going to be 50+KW.. into 20dB.. approx 5MW 
EIRP.  Apparantly, he got 'flashed' several times before he threw 
himself clear, but still ended up with very severe red spots all over 
him (he was behind something with 3 inch holes in it..)

The bottom line is, you won't hurt yourself with 4W EIRP.  It's not 
gonna happen.  But if you see some clown experimenting with a microwave 
oven and a dish, please do him, yourself and everyone else a favour, and 
hit the magnetron with a hammer before he silently kills some poor prick 
across the street.


/sw



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