Correlations between the Interference Statistics of Finnish Radio Systems and EMC Market Surveillance In Finland

In this paper two sets of interference statistics have been compared against those of the EMC market surveillance statistics made by The Safety Technology Authority (TUKES). The main focus has been on electrical equipment. The aim of the paper is to find out whether there is a potential use and usefulness for the applying of interference statistics when evaluating the effectiveness of EMC market surveillance, and also when in allocating EMC market surveillance resources. Also, the costs of EMC market surveillance have been compared against the costs of interference problem resolving. 1 THE INTERFERENCE STATISTICS FOR RADIO SYSTEMS IN FINLAND This section contains statistics relating to identified interferences in radio systems, which have been recorded in Finland. These statistics have been collated by two different bodies; one an authority and the other corporate. The statistics are examined more carefully in those cases where the cause of interference was in electrical equipment. 1.1 The Finnish Communications Regulatory Authority The Finnish Communications Regulatory Authority (FICORA) [1] usually identifies and clarifies reported radio interference cases. In addition, it also carries out active surveillance. Reports on problems are usually the basis for when measures are taken to correct any interference in radio communications. In addition to the Helsinki based Radio Monitoring Centre, FICORA has three radio monitoring stations around Finland. The monitoring of radio communications and the clarification of radio interference is carried out at the centre and the stations. Frequency planning and radio monitoring centre personnel co-operate when clarifying radio interference. Experience gained from solving interference problems is, in turn, utilized both in frequency planning and in evaluating the need for change in technical requirements. The equipment market is monitored in order to ensure that consumers get only radio and telecommunications terminal equipment that complies with requirements and that is suitable for use in connection with other types of radio and telecommunications equipment. Equipment that does not meet requirements can be disturbed by outside sources or cause interference in radio and telecommunications. 1.1.1 Interference statistics Between the years 1991 and 2000, FICORA registered 3,723 cases of interference to radio systems. Fig. 1 shows the proportion of different interference sources. 603 (16 %) of interference cases were found to have been caused by electrical equipment. The annual make up of these cases is shown in chapter 1.3. [2]