This project requires that a callable function be generated wherein a set of inputs describing a 3-D (geodesic) triangle are used to describe a triangle on the earth's surface. The inputs will likely be in the form of latitudes and longitudes. Up to five (5) sets of lats:longs can be input, with triangles generated from all combinations of three sets of lats:longs. Each set of lats:longs will represent a wireless receiver (Ex: a cellular tower). The legs of all combinations of triangles will be computed in light-feet (appx. nanoseconds), thus comprising a series of overlapping triangles.
An additional set of inputs will be in the form of times that each tower receives a wireless signal. The receiving time will be in the form of an absolute time with a clock speed measurable to fractions of nanoseconds.
The purpose of the function is to determine the t0 (T-zero), or originating time of the signal by restating two of the three legs of each constituent triangle in terms of the arrival time minus the t0, and solving for t0 throughout, yielding the originating location of the wireless signal. A minimum of three triangles will be required to resolve the signal source location, with a maximum of five triangles. We believe that Heron's Formula will be the best approach, but we are not fixed on any single solution.
The function will be called from a GIS scripting system, either from MapBasic or an ESRI product.
This software must be completed well in advance of a July 15, 2007 demonstration.
Further information is available as needed.
1) Complete and fully-functional working program(s) in executable form as well as complete source code of all work done.
2) Deliverables must be in ready-to-run condition, as follows (depending on the nature of the deliverables):
a) For web sites or other server-side deliverables intended to only ever exist in one place in the Buyer's environment--Deliverables must be installed by the Seller in ready-to-run condition in the Buyer's environment.
b) For all others including desktop software or software the buyer intends to distribute: A software installation package that will install the software in ready-to-run condition on the platform(s) specified in this bid request.
3) All deliverables will be considered "work made for hire" under U.S. Copyright law. Buyer will receive exclusive and complete copyrights to all work purchased. (No GPL, GNU, 3rd party components, etc. unless all copyright ramifications are explained AND AGREED TO by the buyer on the site per the coder's Seller Legal Agreement).
This system will work within a Windows XP or Vista environment. Calling programs are as described above.