A method for route calculation using real time traffic conditions is
disclosed. A transmission that includes weightings indicative of traffic
conditions on roads is received. Then, a solution route is calculated by
forming a list of road segments. The list is formed by expanding a search
tree comprised of gates. Each gate represents a physical location on a
road segment and an accessible direction relative thereto. Each gate to
which a weighting applies is incremented by an amount indicated in the
transmission. The solution route is determined by expanding the search
tree, which includes determining and evaluating successor gates.