I take it you are running two receivers? Seems to me a software solution is possible.
Do we need to do any more than just average the two? In your example doesn't look like time delays are needed for steering. Mike W9MDB On Tuesday, December 5, 2023 at 09:18:28 AM CST, robert evans LAST_NAME via wsjt-devel <wsjt-devel@lists.sourceforge.net> wrote: Having used diversity reception techniques as far back as the 70s and knowing it was used in the 40s to improve RTTY reception for mil comms, that improvement is possible. An early technique used 2 coherent R-390As and dual fsk demod unit. The antennas were often of different polarization because they knew the fading was often due ordinary and extraordinary propagation though the ionosphere producing changes in polarization. But, sometimes just two horizonal antennas far enough apart offer improvements, for example. Diversity reception made RTTY via the HF ionosphere very reliable in the 40s. Present day wifi benefits from direct sequence spread spectrum but also mimo. Knowing the present code in wsjt does not offer hooks for diversity, but I asked Joe once did it ever or was it once considered? There are now two eme antennas at dvra. N2LO~> > On 12/05/2023 3:34 AM EST Ben Gelb via wsjt-devel > <wsjt-devel@lists.sourceforge.net> wrote: > > > I have been messing around with WSPR decoding on 630m with a pair of > phase-locked receivers and two receive antennas. > > I have put together some software to save two sets of coherent samples > for each 2-minute period, and then after the fact I can combine the > two sets of samples w/ a configurable relative gain and phase shift. > > I then wrote some scripts to call wsprd repeatedly w/ whilst sweeping > the gain/phase parameters, and looking at the change in reported SNR. > > My real aim is to help hear a little bit better (i.e. have a higher > chance of pulling out decodes near the limit) and quantify the > benefit. > > In latest experiment, I am often able to see 2-3dB improvement in > reported SNR from wsprd by tweaking gain/phase parameters. I'm > wondering what this really means. Have I actually improved the SNR > substantially? Or is it possible I am just affecting the SNR > calculation (I think it is roughly measuring the average noise level > in the 2.5kHz window, and comparing to peaks) in a way that doesn't > necessarily imply increased probability of decode? If I happen to have > cancelled some noise outside of the 150Hz WSPR passband, it might > improve SNR but not really matter for the purposes of decoding? > > Are there other metrics within the decoder that might provide useful > feedback for experiments here? > > Thanks for any thoughts/suggestions. > > Ben, N1VF > > > _______________________________________________ > wsjt-devel mailing list > wsjt-devel@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/wsjt-devel _______________________________________________ wsjt-devel mailing list wsjt-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/wsjt-devel _______________________________________________ wsjt-devel mailing list wsjt-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/wsjt-devel
