Quoting Mike Naruta <[EMAIL PROTECTED]>, on Tue 03 Jun 2008 06:12:51 AM PDT:
> I suspect that it is because we always try > to push the limits in ham radio. Sort of > like the hot-rodder tinkering with the > vehicle to squeeze even more performance > out of it. > > > Stereo: why not? Using independent > sideband, we could do that. What better > place to experiment than ham radio? There > are several places in the spectrum where > we can try wider-bandwidth transmissions. > > > If we are dedicated to narrow bandwidth and > efficiency, maybe we should be on CW. CW is unique in requiring perhaps the simplest of all transmitters, although requiring a sophisticated receiver (to get the information out.. not just to convert RF). However, it is not an energy or bandwidth efficient modulation (i.e. the peak to average ratio is 2:1, so you have to run an amplifier with twice the power, compared to some form of constant envelope modulation). Folks who obsess about sending data with the absolute most efficient means (sending back a few bits per second from deep space) tend to use PSK in some form, with a LOT of coding. On HF links, various multitone FSK/PSK schemes are popular, given the particular channel properties. Jim, W6RMK (who designs those deep space radios for a living) _______________________________________________ FlexRadio Systems Mailing List FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kb.flex-radio.com/ Homepage: http://www.flex-radio.com/
