Hardware Suitable Implementation for CNPC Transmission

Command and non-payload communication (CNPC) is one of key enablers for unmanned aircraft system (UAS) to be safely integrated into national airspace by providing a highly reliable link. In the CNPC, the level of unwanted emission in the out-of-band domain should be strictly limited for the support of a highly reliable link without any significant inter-channel interferences as well as the optimized use of CNPC spectrum resources. Moreover, to transmit the various information type, CNPC should be operated on various transmission modes in order to support various data rates which are depending on amount of information sent via CNPC. Those requirements make the implementation of a channelization filter required in a CNPC transmitter. Considering the filter implementation in analog domain for the support of the requirements may lead cost to be increased, a digital FIR filter, which is generally used in conventional communication systems, can be considered. However, a lot of hardware logic resources are required in the implementation of digital FIR filter supporting various transmission modes under the very low level of out-of-band emission. In the paper, in order to solve this problem, we apply to cascaded integrator-comb (CIC) filter and compensation filter for the efficient and attractive hardware implementation of CNPC transmitter with reasonable costs.