[MLB-WIRELESS] belated response

Mark Aitken maitken at erggroup.com
Thu Nov 4 08:01:15 EST 2004


> Vertcal bounced becomes Horizontal, Right Circular  becomes Left 
Circular etc

Hmmmm,  Not quite true.  Wave theory shows that a wave front reflected of 
a perpendicular 
plane will simply mirror itself, it will flip but not by 90 degrees but 
180 degrees.

This is what causes distructive reasonance, ie the inverted phase. 

It is when the wavefront interacts with the reflection surface at "angles" 
other than 0 degrees that 
interferance patterns are set up.

However, it has been seen that ionospheric reflection of a radio wave can 
result in a degree of 
faraday rotation which is not really reflection per see but H plane 
interaction of the wave with a magnetic field.

At best, firing a 2.4 Ghz signal a a flat plane "survey marker" (as the 
original message was about) from probably
not only a horizontal angle but also some angle with a vertical component 
would  result in all sorts of reflected waves
being seen and probably not much of a useful signal.  Most probably 
contributed to the small size of such a surface.
A larger surface area of many 10's of wavelengths would have better 

I have known of Ham Radio Operators reflecting their 10 GHz signals off of 
water towers to get around
hills and it works quite well.

So anything is possible! 



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