Patent ID: 7894979

Claim:
A method for determining turning rates in a road network, comprising: measuring traffic volumes at plurality of measurement cross-sections at a plurality predefined measuring intervals; dividing the road network at least partially into subnetworks with entries and at least one exit; considering at least one subnetwork as a forward-related network; formulating a model equation for the forward-related subnetwork in which measurement cross-sections are based upon the at least one exit and the entries of the subnetwork; setting an exit traffic volume as a weighted sum of entry traffic volumes, wherein a weighting factor corresponds to forward-related turning rates, the weighting factor specifying the portion of an entry traffic volume flowing out through the at least one exit; calculating the forward-related turning rates based upon the model equation; accounting the entry traffic volumes of the plurality of past measuring intervals in the weighted sum for the exit traffic volume of a predefined measuring interval; and determining a forward-related turning rate based upon a sum of corresponding turning rates of the measuring intervals, wherein the model equation is based upon a mathematical estimation method, and wherein an extended Kalman filter is used in the mathematical estimation method.