Fwd: How to get out the maximum from cheap sdrs

Hi All, I would like to realize an algorithm to build the best possible dvb-t sdr experience. The idea is, that no matter how many sdrs and what kind of antenna you have, the software gets the best out of your hardware. This is what I have thought: The user community of a system depends on how useful it is, how easy it is to use, build and how much money it costs. Rtl-sdrs are quite cheap, but for now a user has no benefit of having multiple sdrs in its system. That is why I'm searching a way to correlate the signals of the sdrs without hardware modification. I think everyone of you has seen the noise from the power source. Has anyone tried to build a filter to use that noise to calculate the delay between multiple dongles? I mean, they get the same noise. I don't know if it is sufficient, but it is also a good spot, to put some artificial noise in, as it can be easily accessed and does not interfere with rf circuitry when it is switched off. Is that an useful approach? Do you think this could work? Did I miss something? regards, Steve