A time-domain Correlative Interference Mitigation in LDACS1

Abstract

Given that L-band digital aeronautical communications system type 1 (LDACS1) may share the same spectrum with the legacy Distance Measuring Equipment (DME) system, DME, impulsive interference would be the main issue of this aeronautical communications system. To improve the performance of the LDACS1, a time-domain Correlative Interference Mitigation (CIM) aiming at DME impulse is proposed in this paper. This proposed method could be expected to detect and mitigate the DME interference by utilizing strong auto-correlation of DME signals and weak cross-correlation with LDACS1 signals. In CIM, correlative analysis and time-domain filtering is applied to obtain the information instead of preset thresholds, which is different from the existed impulsive interference mitigation method, i.e., Pulse Blanking (PB). Simulation results illustrate that CIM effectively improves the Bit Error Rate (BER) performance and achieves lower BER compared with PB. Furthermore, CIM can maintain its stability and effectiveness in certain transmission rates and power levels of DME pulse pairs.