This study proposes a performance comparison between the orthogonal chirp division multiplexing (OCDM) and Hermitian symmetric orthogonal frequency division multiplexing (HS-OFDM) schemes in terms of data rate and bit error probability in the context of narrowband power line communication (PLC) systems. To analyze data rate of various power allocation techniques, we consider optimal, sub-optimal, and uniform power allocation techniques. Numerical results show that the OCDM eventually outperforms the HS-OFDM in terms of bit error probability when uniform power allocation applies and the HS-OFDM normalized signal to noise ratio is frequency selective. In contrast, the OCDM offers the lowest data rate performance when all the chosen power allocation techniques are considered. Thus, the OCDM can be more appropriate for low-bit-rate PLC systems when channel state information is not available at the transmitter side and fixed digital constellation is applied.

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This paper investigates the degradation caused by interference resulting from cyclic prefix violation and symbol timing offset in narrowband power line communication systems. In this sense, it presents a unified formulation from which Hermitian symmetric orthogonal frequency division multiplexing (HS-OFDM), orthogonal chirp division multiplexing (OCDM), single-carrier cyclic prefix (SCCP), and orthogonal time–frequency division multiplexing (OTFDM) can be easily derived. The paper then provides closed-form expressions for quantifying the aforementioned interference in the presence of a frequency domain equalizer. The numerical analyses exhibit the performances of these schemes under various data communication conditions, such as the availability of channel state information, the presence or absence of interference, modeling of additive noise as a white or colored Gaussian random process, frequency domain equalizer type, and the use of bit and power allocation techniques. The closed-form expressions and performance analyses regarding achievable data rate and bit error probability provide guidance for dealing with distinct constraints in narrowband power line communication (PLC) systems using the HS-OFDM, OCDM, SCCP, or OTFDM scheme. Lastly, the unified formulation and results obtained motivate the design of multi-scheme transceivers.

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