UFH 400MHz or UHF 800MHz

Greetings all,

I have one important question for a project.

In general terms what is better to penetrate concrete (inside buildings) standard UHF or UHF 800 MHz?

I would be grateful for your help.

Thanks.

Not so much the concrete, but the rebar in the concrete.

There’s a decent paper on it here. http://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1027&context=ceendiss
Graphs of attenuation compared to frequency.

The simple answer is that low frequencies are attenuated less than high, which is what we’ve always been taught.

Simple experience with handheld radios has shown me that VHF does poorly through building; UHF does better and 900MHz is the best.

That fella who wrote the research paper will have to do some re-writing as the absorbtion is worse as frequency gets higher. Interesting question isn’t it?

I don’t write research papers. I just use handheld radios every day.

I have used VHF, UHF and 900MHz spread spectrum radios every single day for many many years.

I can point out a hundred thousand web sites that support what I say, but why bother. He asked. I answered, based on MY real world experience.

Hang on! I wasn’t having a pop, so no need for the slap back - I was pointing out that exactly like you say - real world usage appears to differ.

Care to calm down and consider what is going on then? Wow! talk about over reacting. I wasn’t saying you were wrong, or incorrect, or that I disagree - just commenting that physics disagrees with reality. Neck - wind in!