On 07/01/2010 07:28 AM, Bruce Stansby wrote: > Hi Marcus > > I havn't quiet got my head around coherant dedispersion myself, I use in > coherant. Basically as far as I'm aware it does all the delays in fourier > space. It is generally far superior to the standard incoherant method but for > searching is ineficient as it can not usually be done in real time across a > wide bandwidth. > Yup, I'm well aware of that :-)
> Hence unless your trying to find a signal at a specific DM a blind search > usually uses incoherant, unless you have a cluster at your disposal. If you > are trying to test if the signal is ther for a specific object and not sure > about your disperser then I suggest folding the spectral data at a pulse > period, you can then find it in a waterfall plot of your bandpass. > > or else you can try and download DSPSR and use something that is known to > work, if you can work out the install. > > Regards Bruce > Actually, my frequency-domain coefficient generator is based loosely on some earlier Swinburne code, and then I use the Gnu Radio FFT filter block, after turning the frequency-domain coefficients into time-domain ones (for some bizarre reason, the Gnu Radio FFT filter takes its coefficients in time-domain, rather than frequency domain). Since I won't have a live instrument to connect this stuff to for *months* (http://www.sbrac.org), I wondered if anyone had thought of test strategies for testing a coherent de-disperser prior to "live" tests using real objects. -- Principal Investigator Shirleys Bay Radio Astronomy Consortium http://www.sbrac.org _______________________________________________ Discuss-gnuradio mailing list [email protected] http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
