ISB could also be used to operate a two way communication channel similar to working split frequency.
Simple protocols would need to be established dealing with which sideband is used to initiate a communication. I would imagine these sorts of things would be simple to execute in software. Leif Asbrink wrote: > Hi Jose, > > >> I had never given too much thought to that idea before, but two I/Q ISB >> signals should be used to be translated to the working frequency, using >> the same two carriers in quadrature on the PC. That allows to use >> existent hardware, and I believe it is advisable to use I-Q signals to >> be able to take adventage of image rejection mixers as many designs I >> have seen (Softrock, YU1LM, etc) do to keep spurious outputs low. >> > It is much simpler. We want two independent SSB signals at the antenna. > One LSB and another USB. They should be independent so the (suppressed) > carrier does not have to be the same. Both carriers just have to be > separated by less than the tuning accuracy needed at the receive side. > It is perfectly fine to use two conventional SSB transmitters with > separate antennas. On the RX side you would simply have the summed > electromagnetic field from the two transmitters. > > >
