eCall minimum set of data transmission – results from a field test in Finland

European in-vehicle emergency call system eCall aims to save lives and mitigate consequences of road accidents. eCall minimum set of data (MSD) which contains information on the accident vehicle is transmitted in the beginning of the call in the voice channel opened between in-vehicle system and public safety answering point. The main objectives of the study are to analyse the successfulness of eCall MSD transmission in Finnish fixed-line and GSM networks and to provide information on factors which contribute to the success rate of MSD transmission. The results of the Wilcoxon rank sum test indicated that the signal strength has no major impact on the success or failure of the MSD transmission when the mobile network signal strength measured by IVS is between -80 and -40 dBm. The analysed data included 12 failed MSD transmission attempts and 214 initiated MSDs in total. However, the test results also indicated that the MSD success rate can still be very different in different real-life physical mobile and fixed-line locations.