Simultaneous rx of two RADE streams -- consquences?

[N8HOP]

The documentation says RADE requires 1500hz RF bandwidth. This would fit two simultaneous RADE transmissions into a 3khz space if the tx center of each was offset from the typical 1500hz down to 750hz for one transmission and 2250 hz for the other. 

Has this been tried, and what consequence is this to the receiver?

Would this work for selective reception if the receiver was to bias toward either the 750hz side or the 2250 side? 

Nathan

[Bob Morris]

May want to wait until the CODAC designers get the shoulders down a bit in a future iteration.

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[ma...@flyfast.net]

I can’t speak for a designer, but I will say that the decoder only looks for a single stream today. If you want to run two separate instances of FreeDV, each centered on a different frequency, that is possible. I’d ask, what is your use case? Many transceivers in use can’t see 3KHz as is, so there is a limited number that could decode two streams in a ~3KHz IF. Likewise, if you wanted to choose one to transmit to, the TX bandwidth for most is narrower than 3KHz (the IC-7300 for example, is only 2800Hz.)

 

There is nothing gained for the majority of users by trying to fit two stream decode into a single passband. Just run two instances on separate receivers.

 

Matt

AL0R

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[Pierre Martel]

SDR receive can do much more than 3khz receive at a time. 

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[Mooneer Salem]

I'd be more concerned about how sharp your radio's filters can be and the spectral purity of the other stations. I'm not sure you could have two stations right next to each other but I imagine a few hundred kHz apart would be fine with modern radios.

-Mooneer K6AQ

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