Authenticating Code from Transmitters
 

Not sure the exact way transmitters and receivers work but I understand that on, for example, 72MHz we use crystals to divide the fractional range.

In these days of advanced miniturisation and technology, why dont the radio manufacturers add an authenticating code to the transmitted radio signals to identify a unique transmitter to its partnered receiver. This would eliminate any lockout problems caused by the very likely event of someone switching on whilst on the same channel as someone flying.

An onboard microprocessor (or a more advanced existing processor) in the receiver could verify the signal as coming from the correct transmitter (in addition to the existing channel as it does now).

I really dont see this as being a big deal, however, I dont profess to knowing all the facts on the subject.

RE: Authenticating Code from Transmitters
 

Hi Zack,
Well this tecnology is on it's way but simple it isn't. Copy & paste this link.
http://www.rcuniverse.com/forum/fb.a...ectrum%2Cradio

The problem is difficult to imagine but radio signal are all the same to a receiver. So if you get two transmitters on the same frequency despite the fact that you have uniquely encoded the signal, the rx will be unable to pick the good information out of the bad. The best it can do is confirm that its getting bad information i.e. interference, and go into hold or failsafe mode.
Imagine two people were speaking to you at the same time. One was talking to you about something that you could verify as true, but you had to follow their insrtuction absolutely exactly. The other one was also giving you instructions that you could verify as false but they sounded just like the "true" instructions. If you really concentrated you might be able to do it by listening for the "true" voice; but radio does not have a "voice". So now imagine doing the task again but both the speakers have exactly the same voice!
At the moment we have a technology which if universally adopted would virtually eliminate shoot down incidents, and that is channel check. So far to my knowledge only one manufacturer has introduced this system.
Regards,

john.

RE: Authenticating Code from Transmitters
 

You've explained it extremely well.

RE: Authenticating Code from Transmitters
 

How about a transmitter with a trunking circuit like cell-phone;). You simply dial up your receiver with you own number before flying [8D] The only problem would be dropping signal just like cell phone drops call :D

RE: Authenticating Code from Transmitters
 

I'd say you're right! That could be a problem!

RE: Authenticating Code from Transmitters
 

Yeah great, a radio system with all the reliability of a mobile call; "No network Coverage" comes to mind. " Please try Later"![:@]
Hey, I can crash all by myself, I don't need your help:D

RE: Authenticating Code from Transmitters
 

muhahaha... go out of range and pay roaming charges:):D