At 08:04 AM 8/22/2006, Jerry Flanders wrote: >We are not operating radios - we are operating _modes_ (i.e., ssb >phone OR cw OR rtty OR psk31 OR ... ).
An excellent point! (in the pro SDR world, modes are called "waveforms") >If available, you would probably want several similar consoles, each >with specific enhancements for a particular mode. You would use one >at a time, of course. In a few years, when SDR has become the >dominant type of radio, I think ops will want and have specialized >consoles like this. > >For instance, right now I want a console specific to RTTY contesting >operations - it doesn't need the usual ANF button, but it could >benefit from a different kind of ANF that only removes a multi-second >long constant cw QRM. It doesn't need a CW memory keyer, but a >built-in FFT tuning display/waterfall like MMTTY provides would be >very useful. It doesn't need an audio equalizer, but real FSK would help. Precisely... the UI should display the controls/features/etc that are relevant to the mode in use, and the software should translate that into appropriate actions for the radio hardware. The tricky aspect is where to draw that line... Here's a concrete example: The SDR has the ability to essentially use ANY arbitrary IF filter characteristic (with a few limitations). So, should the interface between the UI and the "radio" be: a) an array defining the complex weight for each frequency bin? b) a couple numbers defining upper and lower 3dB frequencies? (but what about skirt steepness?) c) a couple numbers defining center frequency and bandwidth d) a rise and fall time spec e) an algebraic expression of arbitrary complexity defining a frequency or time domain response? If I were a "radio" builder, and I did my filtering in frequency domain with a fast convolution sort of approach (FFT, multiply, IFFT), I'd want people to give me the array of complex numbers If I did my filtering using timedomain digital filters, I'd probably want some numbers to feed into a utility that calculates tap coefficients It gets even more complex when you want to define an interface for such fancy (but, really, really handy) things as specifying notches as well as passbands, especially if the backend radio has the ability to track an interfering signal. Jim Jim _______________________________________________ FlexRadio mailing list FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archive Link: http://www.mail-archive.com/flexradio%40flex-radio.biz/ FlexRadio Homepage: http://www.flex-radio.com
