Method and device for adjusting at least one parameter of a communication system

An apparatus for adjusting at least one parameter of a communication system between two subscribers, wherein one subscriber is a mobile transportation vehicle, wherein at least one parameter is changed based on an estimated future the channel quality, wherein the apparatus is designed such that at least a current position of the transportation vehicle is captured or determined at a time and a future position and environment are estimated based on the current position, captured objects and their properties and a speed and movement vector of the subscriber at that time using digital road maps and an environmental model, wherein the future time is in a seconds range, wherein the channel quality for a future time is estimated therefrom, wherein at least one parameter of the communication system is adjusted based on the estimation, wherein the communication system carries out OFDM modulation, wherein the at least one parameter is a cyclic prefix of a transmission symbol, wherein the channel quality is estimated based on an estimated K factor, wherein the K factor indicates the ratio between direct power between the subscribers and power received via reflection, wherein, in response to a K factor being within a range around 1, a length of the cyclic prefix is set to a maximum of a delay of a reflection component provided only one or more previously known reflection components are being estimated.