ELECTRONIC MANAGEMENT SYSTEM OF AN AUTOMOBILE

Electronic Management System Of An Automobile



Electronic Management System of An Automobile

Introduction

Various broadband services are currently being widely used and the number of Internet subscriptions in Japan is now over 150 million* . The NTT Group is taking up the challenge of constructing a reliable, secure, and convenient telecommunication network on the basis of its medium-term management strategy . That challenge involves both connecting various systems and devices to the telecommunication network and increasing the system capacity and functions. These increases in telecommunication system scale and capacity may also increase the social impact of any failure in the system. At the same time, the electromagnetic environment that surrounds telecommunication systems is getting more and more complex with technological advances, such as progress in high-frequency technology, the use of various electrical and electronic devices, including telecommunication equipment, and the problem of noise that accompanies inverter technology used for greater energy efficiency (Lee 2004 8). Lightning-induced failures are also creating new kind of problems as telecommunication systems change. The issues to be considered in an IP (Internet protocol) network infrastructure are shown in Fig. 1. Various kinds of trouble may occur when there is a change in the environment at a telecommunication center building or a customer's premises. It is important for electromagnetic compatibility (EMC) technology to advance in step with telecommunication networks if we are to construct secure and reliable networks. We consider EMC to be an important technology for supporting network reliability from the fundamentals of telecommunication. In this article, we explain the approach that the NTT Group is taking to EMC and how EMC is being applied in telecommunication networks.

EMC requirements in NTT Group

NTT Group specifications concerning telecommunication EMC are created as internal standards and technical standards, thus simultaneously achieving compliance as a company and improvements in the procurement of equipment, systems, etc. with respect to EMC.

Regulation of EMC in NTT began with the establishment of the “Internal Standards for Electromagnetic Disturbance Emitted from Telecommunication Equipment” in 1994. In 1998, the “Internal Standards for Immunity of Telecommunication Equipment” were established. Then, in 2001, those two standards were integrated as the “Internal EMC Standards for Telecommunication Equipment”. Those internal standards were newly revised by including requirements for overvoltage and overcurrent in telecommunication equipment in 2003, as common standards for deciding on telecommunication system procurement specifications. These internal standards are currently being applied in NTT Group. They mainly describe the approach to EMC requirements and application methods for emission, immunity, and overvoltage, etc. The verdict related to “Limits and Measurement Methods for Electromagnetic Disturbances Emitted from Information Technology Equipment” in the Japanese national committee of CISPR (Comité International Spécial des Perturbations Radioélectriques), which is overseen by the Ministry of Internal Affairs and Communication, led to the decision that telecommunication equipment in NTT's centers should comply with self-set limits on electromagnetic disturbances, while terminal equipment and other such devices provided by NTT should comply with the VCCI (Voluntary Control Council for Interference by Information Technology Equipment) technical ...