Think OP has the Choice of 3 bands Sent from my iPhone
On Feb 5, 2013, at 12:32 PM, Chris Albertson <albertson.ch...@gmail.com> wrote: > On Mon, Feb 4, 2013 at 9:17 PM, Hal Murray <hmur...@megapathdsl.net> wrote: > >> Can you re-transmit on a nearby frequency without blasting the receiver off >> the air? > > No not if it is in the same band, filters are never that good. I > thought the OP had several bands available. > > So if this all needs to happen at one RF frequency the transmitter > needs to act like a radar and send out modulated pulses. The > oscilator that does the modulation (sawtooth?) needs to run > continuously. so that the phase of the returned signal can be > compared. If you don't know the range you need a conservative > pulse repetition frequency (PRF in Radar speak) then once you find the > range you can use a faster one to collect better data if you need to. > The fester PRF transmits on average more energy so you get better data > > The advantage is that all the "smarts" is in just one place, all the > other units are simply a "mirror with gain" or "bent pipe". > > The next level of sophistication is to scan the antenna and note the > azimuth position when the signal is maximum. Then you have both range > and diction. No need to triangulate. > > Radars sound expensive but go to any small boat marina and you see > that even small boats have them. The newels units integate with GPS > and the boats auto pilot and still prices at retail level are under > $2K for entry level systems. > > All that said, why not simply use GPS? Your mobile unit can have a > GPS receiver and transmit is location. This works ten times better > and cost a lot less. The cell phone industry gave up on > triangulation when GPS because cheap and easy > > -- > > Chris Albertson > Redondo Beach, California > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.