Sorry, that was just a way I referred to the process.
What I was referring to is described here:
bjblscan
It is a way to generate a VERY SLOW spectrum scan, ie about 9 minutes per scan.
Basically, it only works with a Broadlogic 1030 computer card receiver.
A fellow called Hans (last name I can't spell, but he wrote the DVBAPPS program) wrote an application that would generate a text file of frequency vs signal strength using the Broadlogic 1030. I think he abandoned the project since the BLSA thing became more popular, and his program is no longer available at his web page, but I can give anyone interested a copy. I had the 1030, however, and the BLSA doesn't work with that, so I wrote a little VB program that would plot out the text file that Hans' program generates, and it also allows you to drag your mouse across the signals to identify the frequency of signals, and it gives an estimate of the SR via the width of the peak. I've found that it generally identifies the freq to within 1 or 2 MHz, but the SR estimation isn't very good, as it depends upon where on the peak you drag. The image at the above web page shows a version which doesn't estimate the SR, mainly because it wasn't very accurate, but anyone interested in the newer versions, I can provide the newer version.
It only works with the 1030 card, so it won't be of any interest to people who don't have this receiver. The 1030 receiver is nice due to it's interesting control app, as well as this spectrum capability, however it doesn't seem to have any DiseqC capability, so I generally have to use it slaved, since it can't select switch positions.
THe spectrum plots, however have been a way of locating DVB-S2 signals, since blind scan receivers for DVB-S2 are rare. In fact the particular sat (which I don't want to identify) that I was scanning has about 23 DVB-S2 transponders that I found with the program, plus SR determination via the shortwave method, although only one of these transponders ever have viewable video. So although it is VERY SLOW, I think it's quite useful, and I use it all the time.