Something to contemplate for future incarnations is the ability to synchronize the audio streams (I/Q and/or baseband) from multiple radios, preferably on separate computers, but even on the same computer.
If one wants to do "interesting" things requiring coherent processing, like diversity combining or phased arrays, you need to be able to match up the received signal from one antenna/radio with others. The reason I point this out is that a friend mentioned to me that while there are lots of flexible audio support packages out there (PortAudio, Jack, ALSA, etc.) not all of them offer the ability to synchronize to an accuracy of one sample. In general, systems designed for multimedia (where you have to sync to video frames) are more likely to provide this, at least to milliseconds, although he was unsure if they were good to microseconds (i.e. 1 sample time at 96 ksps is about 10 microseconds). There are, of course, issues when the sample streams have slightly different underlying rates (as, for instance, if you are combining streams from two different audio interfaces), but that's a lesser problem than just making sure the buffers are lined up (or that they have a fixed and knowable offset). Or maybe this is something totally out of scope for PowerSDR and it's descendants.. Jim, W6RMK _______________________________________________ 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
