We've looked at a few of the product catalogues, but that's about it. Part of a comprehensive program to look for these devices would be to translate the operational requirement into a technical requirement and then look at the devices available that meet that technical requirement in principle and according to the manufacturer. Then they would have to be evaluated in a wide range of circumstances, because the technical requirements—or the catalogues, if you will—provided by the manufacturers tend to tell you the best performance in the best-case situation. They don't really allow you to truly understand the limits of the devices. So you'd have to go out, buy some of these, and test them.
