Performance comparison of new waveforms applied to DVB-T2 transmissions

Abstract

In this paper, Universal Filtered Multicarrier (UFMC) and Filter Bank Multicarrier (FBMC), the promising filter based waveforms are proposed in Digital Video Broadcasting Terrestrial, second generation (DVB-T2) as an alternative to Orthogonal Frequency Division Multiplexing (OFDM). While no filtering operation is carried out in OFDM, the filtering in UFMC is done on groups of subcarriers and in FBMC on each subcarrier. Due to their filtering characteristics, different types of tools such as Power Spectral Density (PSD), spectral efficiency and Bit Error Rate (BER) are used to compare them. These waveforms are simulated in urban environment using a Power Delay Profile (PDP) of the Typical Urban 6 (TU6) channel. The Zero Forcing (ZF) equalization technique is used for OFDM and UFMC simulations while, in the case of FBMC, an equalizer based on frequency sampling is employed: the Complex Finite Impulse Response (CFIR) with 3 taps. In term of spectral efficiency, UFMC and FBMC are respectively 128% and 133% spectrally more efficient than OFDM. Simulation results show that the PSD of FBMC presents better Out Of Band (OOB) than that of UFMC which in turn presents better OOB than that for OFDM. Furthermore, for 32K mode, FBMC and UFMC present respectively a performance gain of 1 dB and 1.2 dB at a BER of 1$0^{-3}$ when compared to OFDM. This paper gives rules about the compromise to establish between spectral efficiency, performance gain and complexity of both UFMC and FBMC waveforms. The choice of FBMC as an alternative to OFDM in DVB-T2 system induces a high spectral efficiency and a better performance gain with a cost of increased complexity whereas the choice of UFMC induces a medium spectral efficiency and a noticeable performance gain with a complexity comparable to that for OFDM. This paper proves that UFMC waveform is the good compromise.