Improved spectrum agility in narrow-band PLC with cyclic block FMT modulation

Narrow-Band power line communications (NB-PLC) operate in portions of the 3-500 kHz spectrum and have to obey certain spectral masks for EMC and coexistence issues. Although orthogonal frequency division multiplexing (OFDM) allows simple spectrum management by switching on-off the subchannels, its poor sub-channel frequency selectivity translates into a poor spectrum usage. An agile use of the spectrum and higher spectral efficiency can be obtained with filter bank modulation. In particular, in this paper, we investigate the use of cyclic block filtered multitone (CB-FMT) modulation and compare it to pulse shaped OFDM (PS-OFDM) deployed in the G3-PLC and IEEE P1901.2 standards. The comparison shows that higher spectral efficiency and improved spectrum management can be achieved with CB-FMT.