A novel pilot scheme for 5G downlink transmission

The paper considers the structure of pilots for downlink transmission in a future 5G radio access system. Based on the OFDM signal parameters proposed for the 5G system by Mogensen et al., we suggest to apply a periodical filtered CAZAC sequence in the time domain. We demonstrate the low computational complexity of channel impulse response estimation and its better accuracy if it is based on our time domain pilot sequence as compared with the pilot sequence placed in the frequency domain and based on Zadoff-Chu sequences. The presented link level simulations show the superiority of our pilot design proposal with respect to frequency domain pilot sequences.