From: tgg@otter.hpl.hp.com (Tom Gardner)
Subject: Re: Can Radio Freq. Be Used To Measure Distance?
Organization: Hewlett-Packard Laboratories, Bristol, UK.
Lines: 24

In sci.electronics, rgc3679@bcstec.ca.boeing.com (Robert G. Carpenter) writes:

> I'm wondering if it's possible to use radio waves to measure the
> distance between a transmitter(s) and receiver?

Yes. It's called RADAR.

> Seems to me that you should be able to measure the signal strength
> and determine distance. This would be for short distances (2000 ft),
> and I would need to have accuracy of 6 inches, or so.

Depends on the environment: in a static environent such as a waveguide yes, in
a dynamic environment (with objects moving about) the multipath kills this
concept.

> How about measuring vertical distance as well, any chance - or am I getting
> ridiculous?

What is the difference between vertical and horizontal?

> What frequencies would be best for this? Or does matter?

This depends on the required range, the required accuracy, the allowable
ambiguity in range, the frequencies the FCC (etc) allow you to use.
