Patent ID: 9449509
Filing Date: 2016-09-20
CPC Classification: B60W,G08G

Claim Text:
1. A computer-implemented method of traffic congestion estimation in a vehicle, comprising: detecting, by a sensor, a speed of a host vehicle in a predetermined period of time and outputting a speed detection result; analyzing, by a processing device installed in the vehicle, a frequency of the speed detection result and outputting a power spectrum that dynamically changes according to the frequency of the speed detection result; detecting, by the processing device, a slope of the power spectrum in a predetermined frequency range and outputting a slope detection result; calculating a spectrum of time variation of the slope within a predetermined time interval and outputting a time variation calculation result; estimating, by a navigation device, an occurrence of traffic congestion based on a current position of the host vehicle obtained from a global positioning system and the time variation calculation result of the slope, and outputting an estimation result; wherein the estimating comprises: in response to detecting that an extreme value of the spectrum of the time variation of the slope is greater than or equal to a predetermined value, determining, by the processing device, a speed variance of the host vehicle indicating that a traffic congestion is likely to occur due to an increasing number of vehicles in front of and in a traveling direction of the host vehicle; and in response to detecting that an extreme value of the spectrum of the time variation of the slope is less than a predetermined value and detecting traveling conditions of vehicles in front of and in the traveling direction of the host vehicle, determining, by the processing device, a speed variance of the host vehicle indicating that a traffic congestion is uncertainly to occur due to a decreasing number of vehicles in front of and in the traveling direction of the host vehicle; and canceling an execution of a vehicle distance adjustment operation which automatically adjusts a vehicle to vehicle distance between the host vehicle and a preceding vehicle when the estimation result indicates the occurrence of the traffic congestion.