Design of a low complexity filter bank satisfying LDACS1 spectral mask specifications for base-station receivers in air-ground communications

The sustained air traffic growth worldwide has resulted in the need for upgrading the existing global air traffic management (ATM) system. Consequently, a new standard called L-band Digital Aeronautical Communication System (LDACS) is being developed for the air-ground communications component of the next generation ATM systems. Amongst the options being considered for LDACS, the LDACS type 1 (LDACS1) is the most superior and mature candidate and is likely to be the final choice for deployment. The presence of previously deployed and operational legacy systems in the L-band has led to stringent spectral mask specifications for LDACS1, to ensure there is no interference caused to the former. In this paper, we propose the design of a digital filter bank which can satisfy the LDACS1 spectral mask specifications while also achieving low complexity of implementation. Design of the proposed filter bank is based on the improved coefficient decimation method. With the help of a design example, we show that when compared with the discrete Fourier transform based filter bank, the proposed filter bank achieves 71.49% reduction in multiplication complexity.