# An Intelligent Parking Management System for Urban Areas
## 1 Introduction  
Human mobility is a necessity in today's world. It has a significant impact on both quality of life and the economy of modern societies. Transport systems are, therefore, a key element in developed or developing countries. [PERSON] [1], in his survey of Intelligent Transportation Systems, indicated that 40% of the world's population spend at least one hour on the road every day. Of all the different modes of transport, the one that is used on a massive scale is land transport by road. Such large-scale use of this type of transport has led to congestion problems in densely populated metropolitan areas, with all the concomitant negative consequences. According to [PERSON] [2], these negative consequences include pollution and its harmful effects on the environment and human health. Too much time on the road means an increase in energy consumption, which has a negative impact on both individual and national economies, as well as on the environment. Several medical studies [3] have confirmed that road transport congestion results in a deterioration of public health because it increases the risk of heart and respiratory diseases. Moreover, according to the WHO, over 7 million people die every year from health problems caused by pollution.  
One of the causes of this excessive amount of time spent on the road in private road transport is the need to spend time looking for free parking spaces. [PERSON] [4] studied the costs generated by the extra distance vehicles have to travel to find a parking space in the cities of Madrid and Barcelona. The costs in consumption for the extra distance and time spent on the road are approximately 347 million and 268 million euros per year, respectively. Public transport authorities and the operators of parking spaces are evaluating various solutions to improve parking space management. Solutions based on infrastructure investment are expensive and implementation is slow. Technology-based solutions have been proposed as an alternative with lower costs and faster implementation.  
In this article we describe a low-cost, minimally-intrusive system for the efficient management of parking spaces on both public roads and controlled zones. This system is based on wireless networks of photoelectric sensors that are deployed on the access roads into and out of these areas. The sensors detect the passage of vehicles on these roads and communicate this information to a data centre, thus making it possible to know the number of vehicles in the controlled zone and the occupancy levels in real-time. This information may be communicated to drivers to facilitate their search for a parking space and to authorities so that they may take steps to control traffic when congestion is detected.  
The article is structured as follows: a selection of related studies is described in the second section, to provide context for our proposed system. The third section describes the system, explaining its general architecture, its main constituent elements, and the method developed to detect the passage of vehicles. Tests to verify system operation are described in the fourth section and, finally, the main conclusions are presented in section five.