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Registered Member #1517
Joined: Wed Jun 04 2008, 06:55AM
Location: Chico CA
Posts: 304
Hi guys,
This is a very fuzzy thing to calculate manually. I was wondering if anyone knew from experience how well certain frequencies deal with propagation through/ around buildings, solid obstructions. I am trying to pick a band for some HSMM experimentation. Just wondering if anyone had any suggestions.
Registered Member #902
Joined: Sun Jul 15 2007, 08:17PM
Location: Pacific Northwest USA
Posts: 1042
Dosinski wrote ...
30 Hz is used by submarines. 300 Hz is used in deep mine shafts. Though I'm not sure how effective those frequencies are inside of buildings.
30 or 300 Hz for HSMM? - that's not right
HSMM stands for High Speed Multi-Media, which operates in the microwave range.
Have you considered the ARRL Microwave Handbook? - I have a copy I'm not putting to use somewhere, maybe I can find your information there, I'll take a look.
-Jimmy
EDIT: the Amateur Band which overlaps with the WiFi band is pretty reliable. A well placed antenna and a good antenna on the user end can work well in urban environments, but you are limited as you get farther away unless it is a strait shot - you could use "range expanders" with the WiFi band as they can seamlessly integrate things
Registered Member #1517
Joined: Wed Jun 04 2008, 06:55AM
Location: Chico CA
Posts: 304
I was thinking about setting up a temporary microwave repeater on a hill or something...
I am trying to rule out the possibility of using 33cm or longer bands. Atmospheric propagation is discussed and I can find results easily, but when it comes to LoS transmission through a building or something, nothing can really be said about penetration vs. frequency.
The ARRL handbook sounds promising though, I'll be looking that up today.
Registered Member #1667
Joined: Sat Aug 30 2008, 09:57PM
Location:
Posts: 374
I guess I won't be of much help here but I once stumpled upon some interesting studies about wave propagation in tunnels, much like it is done here: and here:
perhaps the drain system is worth testing *cough* .. just a thought you can't get your hands on a Multiphysics license, can you?
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Heuristics for propagation
you can't get your hands on a Multiphysics license, can you?