I am seeking a document which can be downloaded, and which contains a relatively basic introduction to Time-Delay-Of-Arrival analysis, of the kind that might be used for locationing in, say, a GPS, or similar system. I'm a tech writer; the company I work for is doing some work in this area, and I'd like to get a bit more background. I've done a Google on the subject, and there is no shortage of documents out there; the problem is finding one at the right level for my needs. I find some articles which are clearly for popular audiences, and others which assume at least a Masters in EE or digital signal processing. I'm somewhere in between. I need something which: 1. Is at roughly sophomore/junior level of engineering math. 2. Has illustrations to accompany the math (I need a bit of hand-holding with my math) 3. Preferably covers at least two or three different algorithms. Any leads/links would be greatly appreciated. Steve O. Standard Antiflame Disclaimer: Please don't flame me. I may actually *be* an idiot, but even idiots have feelings.