Method for calibrating traffic flow basic map parameter on the basis of microwave data

Abstract

The invention relates to a method for calibrating a traffic flow basic map parameter on the basis of microwave data. The method comprises steps of: reading original data, setting an equivalent vehicle length, and calculating a density value; second, setting the adjusting ratio d1 of the equivalent vehicle length, eliminating a ratio dp of noise points, the bandwidth dm of the noise points, limit of error threshold critical density e<Kc>, a traffic capacity eC, and a block density e<Km>; third, equally proportionally eliminating noise points on the left side and the right side of the critical density in order to guarantee that the eliminated noise point range does not exceed a maximum bandwidth; fourth, linearly fitting a front segment and a rear segment, wherein a fitted straight line in the front segment is required to pass an original point, and a fitted straight line in the rear segment is required to pass a block density value point; and determining whether fitted parameters satisfy a condition of convergence, ending calibration if yes, or adjusting the equivalent vehicle length and recalculating the density if not, and going to the third step. The method is simple, effective, and convenient to operate, and solve the limitation of a conventional traffic parameter calibrating method.

Description

technical field [0001] The invention relates to the field of traffic information engineering and control, in particular to a microwave data-based method for calibrating parameters of basic traffic flow diagrams. Background technique [0002] In recent years, there have been more and more natural disasters caused by the high incidence of meteorological disasters. At present, various industries in the society attach great importance to the construction of emergency communication systems. The existing emergency communication systems meet the business needs of disasters and emergencies. However, there are still several business challenges: (1) There are still deficiencies in the all-round access of video mobile ground and air. An extension of the video signal acquisition method; (2) At the same time, due to the remoteness and concealment of the disaster place, the wireless signal transmission of the emergency communication system is often blocked by mountains and buildings, whi...

AI Technical Summary

Problems solved by technology

However, there are still several business challenges: (1) There are still deficiencies in the all-round access of video mobile ground and air. An extension of the video signal acquisition method; (2) At the same time, due to the remoteness and concealment of the disaster place, the wireless signal transmission of the emergency communication system is often blocked by mountains and buildings, which affects the transmission quality and quality of the wireless channel. business flexibility

The existing emergency communication system can reach 5-10km signal coverage, but my country has a vast territory and complex terrain, and power tower lines are often distributed in sparsely populated valleys, which are severely blocked and difficult to reach; it is urgent to use air signal relay to build Internal and external wireless communication bridge

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