Bit Error Rate Validation for Aeronautical Communication System LDACS for Higher Modulation Schemes

The L-Band Digital Aeronautical Communication System (LDACS) is a new aeronautical communication standard between an aircraft and a ground station, which provides high data throughput with different modulation and channel coding schemes for reliable transmission. Conducted measurements of the LDACS receiver (RX) prototype have shown that the Bit Error Rate (HER) severely suffers for higher modulation schemes, while for lower modulation schemes, the results perfectly match with the stated ones in the LDACS standard. This paper evaluates the BER performance for all defined link types, modulation schemes, and channel types by simulations. As a matter of fact, some modulation and coding schemes defined in the LDACS standard show a strong degeneration of the BER for some channel types. Therefore, the different channel types are analyzed in this paper, and the pilot grid spacing is examined according to the underlying channel realizations regarding the phase variations of the channel by adjacent orthogonal frequency division multiplexing (OFDM) symbols.