Future traffic management systems require a bidirectional communication between roadside beacons and vehicles. Several studies are concentrated on a short range microwave link for this application. Multipath fading effects, due to reflections on the road, vehicles or buildings, may interfere with the communication. In this paper, antenna and frequency diversity techniques are considered for a solution of the multipath fading problem. The results demonstrate that an efficient improvement of the link performance can be achieved. >

A study on diversity techniques in a 5.8 GHz microwave link for traffic management systems

Individual traffic management systems are considered as a solution of the problems caused by increasing road traffic. For bidirectional communication between roadside beacons and individual vehicles, a transmission system with a radio link operating at 5.8 GHz is a suitable medium. To study the link performance in multipath fading channels, a deterministic channel model was derived. Calculations, considering the radiation characteristics of the antennas as well as the reflectors 'motorhood' and 'road', are already confirmed by measurements. Since the mobile channel is in general composed of further reflectors, e.g. cars or trucks, the deterministic model was extended by including additional statistical distributed reflectors. The simulation results presented give information on the average power delay profile. Furthermore, the effect of polarization of beacon and the vehicle antenna on communications is discussed. >

Investigation on propagation characteristics of a short range radio link with statistical distributed reflectors

The purpose of this paper is twofold First, it compares the latest European achievements in this field, originating mainly from a cooperative European project (ESPRIT 2016, TIP BASE) with the state of the art all over the world confirming the strong position of the European industry in this particular sector Second, it asks for confidence in the enormous unbroken potential of silicon bipolar technology This potential consists of the fast developing silicon processing techniques (driven by the mainstream VLSI technologies) in combination with new materials enabling both permanent further scaling of existing device concepts as well as the introduction and realization of new device configurations

Recent Progress in Silicon Homo- and Heterojunction Bipolar Technology

A suitable transmission medium for future individual traffic management systems is the short range system with a radio link operating at 5.8 GHz. In multipath fading channels reflected waves may produce interferences in the communication. In this paper, space diversity and polarization diversity are discussed as a solution to meet these problems. Investigations are based on a statistical channel model. This model is an extension of a deterministic model, which is already confirmed by measurements. >

Space diversity and polarisation diversity enhance the performance of a 5.8 GHz radio link for traffic management systems

Short-range microwave communication links in traffic and transport can be used for automatic debiting, navigational aid, collision avoidance, and traffic flow improvements. Some examples of existing systems are presented. A review of future requirements is given and is illustrated by presentation of some experimental systems in the frequency range 2.4-60 GHz which are being studied in Europe. >

B. Hane

Papers

Short range microwave links for traffic and transport applications