When establishing a wireless connection, the capacity and therefore the throughput is important. The communication system consists of a number of components and subsystems. It is a complex system with digital and analog subsystems and much software. Customer experience is of high importance and the quality of the communication system is very important. Testing the entire communication system in a car is therefore of high priority. In addition, a growing percentage of the vehicle’s technical performance depends on how well the communication system works. All this shows that tests of the communication system are a vital part of the development process of new vehicles.

A wireless communication channel uses a space in the frequency spectrum. In order to use the frequency space as efficiently as possible the frequency spectrum is divided into areas that can be used for different purposes and functionalities. The frequency space is then used for transferring digital data at a certain speed (capacity/throughput). To be able to communicate with as high capacity/throughput as possible, different modulation technologies are being used. High order modulation scheme enables high data rates but will also require a high signal-to-noise ratio (SNR).