Efficient message transmission method for in-vehicle emergency service

In the event of a traffic accident it is very important to deliver emergency messages to the Public Safety Answering Point (PSAP) as soon as the accident occurs in order to help the ambulance and other rescue teams arrive at the scene to offer emergency treatment. The PSAP needs to know at least the location of the accident. The main communication network used to transfer data to the PSAP from the in-vehicle emergency system is the internet or by using normal calls. Therefore, if the user is unconscious or has no access to the internet, the emergency message cannot be completed and the mobile operator cannot exchange data with the PSAP. In this paper, a solution is proposed to use the control channel instead of the data channel to receive emergency messages from the vehicle. The main advantages of this solution are that the connection between the user and the PSAP is always available and the message will transmit even if the user is unconscious.