HYPRES SDR on a chip, ADC, and DRM note "The fundamental limit for analog to digital conversion defined by the Nyquist criterion reveals that conventional electronics are simply too slow for the implementation of true software defined radio at higher frequencies. However, this barrier can be overcome with digital and analog circuits based on superconducting electronics." -Wes Littlefield ...Defense Electronics by RF Design magazine >From the above article it was also demonstrated that the idea (which we >discussed earlier on at the soft_radio group of Alberto I2PHD) of using ADC >immediately after the QSD section is being looked at by the defense >electronics corporations devoted to SDR. It also appears that soon there will >be many SDR receivers and transceivers for use in the HF to GHz range, on a >single chip. Some of these will use the ADC idea. I can not say if these >chips will have an on board DDS section. It appears that some of them may >include a DDS section in due course of development. The company to search engine for; to watch for these chips is "HYPRES," no website was given in the article. It appears that the ADC idea was first tossed around at soft_radio group as far as I know. I recall some folk looking into it and getting chips but do not know whats become of that idea? >>>Note: Lately I have been getting a good DRM signal @ 9.8 MHz from RCI in >>>Canada, here in Kentucky. I am amazed that the sound quality is better than >>>FM Stereo broadcast and is more CD quality. You can not even tell by >>>listening that you are listening to HF, one might mistake the format as >>>being a satellite transmission. If you have not had a chance to check out >>>DRM, then when you can, make it a point to to try it out and I am sure it >>>will please you. Now as for the broadcast content of RCI I must admit it is >>>sort of mediocre and needs some more music. RCI is not supporting graphics >>>or other multimedia with its DRM transmission, only basic text data on the >>>transmission itself and QTH. What music they do air is quite nice to listen >>>to and demonstartes some awesome fidelity. DRM is compatible with your QSD I/Q output if you are using a QSD rather than a wideband DRM mixer i.f. output section. The DRM software can automatically detect a I/Q signal as the input method.
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