Systems based on approximation methods using a sufficiently large number of road signs or check points (CP), the exact location of which are known in the system in the city, a network control areas. The location of the vehicle is determined as the passing of the kp. Personal code is transmitted in the CP-board equipment, which, through a data subsystem transmits this information, as well as a unique identification code to the control subsystem and data processing. Thus, the implemented method of direct approximation. However, in practice most often used method for approximating the inverse – the detection and identification vehicles by using applications installed on them active, passive or semi-active low-power radio beacons that transmit to a receiver kp own individual code, or by using optical equipment reading and recognition of the characteristic features of an object, for example, car number plates. Information from the cp further transmitted to the control subsystem and data processing.
Obviously, for the zonal system positioning accuracy and frequency of updating depends on the density of cp in the territory of the system. Approximation methods require the development of communications infrastructure for the organization of a subsystem data from a large number of cp at the center of command and control, and in the case of optical methods for reading and require complex equipment to the cp, and therefore are very expensive to construct systems that cover large areas. At the same time, inverse approximation methods can minimize the amount of on-board equipment – Radio Beacon, or just do without the equipment installed on the vehicle.