On 3/4/07, Dieter <[EMAIL PROTECTED]> wrote:
Will OGC be able to output arbitrary waveforms, or only video? If OGC can generate sine waves, square waves, triangle, etc. it would be very useful as a piece of test equipment. It could be a tracking generator for the spectrum analyzer?
I thought it would be interesting to generate RF signals entirely in the digital domain and use a video DAC to turn it into analog. For instance, you can have a sine-wave generator, that's completely digital, and it has parameters that you can use to adjust the frequency, within a band. BOOM. You have an FM transmitter. Attach an amplifier, and you can send audio to a nearby radio. Say we could do this where we mix a complete TV signal, on channel 3/4, video with color subcarrier, and the audio channel. Voila. No more need for a TV chip, and we can get both s-video and encoded. If the granularity of our control of the signal is 330Mhz, can we encode all of the information in the TV signal? Would the steps between digital levels (1024 of them) be too noisy? Could we fix that with a low-pass filter? I do know, for instance, that IP-over-power-line decoders do everything in the digital domain. If you were to transmit the signal on a single band, the amplitude would interfere with electronic devices, so they use multiple low-power channels instead. The decoder doesn't use caps and inductors to decode each channel, however. They use a band-pass filter that gets all of the channels at once. Then they digitize it and use a taylor series approximation of a FFT to split out the channels entirely in the digital domain. We would be doing this in reverse, which is even easier. -- Timothy Normand Miller http://www.cse.ohio-state.edu/~millerti Favorite book: The Design of Everyday Things, Donald A. Norman, ISBN 0-465-06710-7 _______________________________________________ Open-graphics mailing list [email protected] http://lists.duskglow.com/mailman/listinfo/open-graphics List service provided by Duskglow Consulting, LLC (www.duskglow.com)
