DSP-assisted channel aggregation options for next-generation mobile fronthauling

In this paper, we perform a performance comparison of two digital signal processing (DSP)-based channel aggregation options, such as Time Division Multiplexing Access (TDMA) and Frequency Division Multiplexing Access (FDMA) in the next generation mobile fronthauling. The two DSP-based options are here compared for the scenarios of 48 (20 MHz) LTE-A, 96 (20 MHz) LTE-A or 24 (100 MHz new radio NR) channels by means of simulation on realistic Intensity Modulation and Direct Detection optical fronthauling link, in terms of spectral occupation, DSP complexity and error vector magnitude (EVM) as a performance metric. We verified that TDMA option has compact bandwidth, it does not require pre-emphasis to equalize per channel EVM and gives out better EVM performance when the optical channel shows significant frequency roll-off towards higher channels as compared to FDMA without pre-emphasis equalization.