The present disclosure relates to a method to introduce complementing training symbols into a 802.11p OFDM frame in vehicular communications, wherein a transmitter sends encrypted information from a first unit to a receiver of a specific second unit or a respective receiver of a number of second units and wherein fixed training symbols, which are implemented in a transmitter chip, are multiplexed with the information and transmitted to the receiver for channel estimation at the receiver side. In order to improve channel estimation complementing training symbols are inserted at the transmitter side immediately after an LLC sub-layer, where the LLC sub-layer is software defined and can be modified. It also relates to a receiver for exploiting the inserted complementing training symbols in order to improve channel estimation in 802.11 p OFDM vehicular communications, which is arranged to reproduce the complementing training symbols inserted in accordance with the method.