###### Abstract  
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. p 2  
rate (BER) [6; 7; 8; 9; 10; 11]. It can even be used with a blanker to mitigate impulsive noise disturbances [12; 13]. Moreover, the single carrier cyclic prefix (SCCP) scheme was considered as an alternative to the OFDM in [14], showing competitive BER performance in comparison to the OFDM when the normalized signal-to-noise ratio (nSNR) in the frequency domain is not frequency selective. The orthogonal division multiplexing (OCDM) scheme, which combines the orthogonality principle with the chirp spread spectrum (CSS) to yield a multichirp scheme [15], was first applied to PLC systems in [16]. The attractiveness of the OCDM scheme relies on the use of the discrete Fresnel transform (DFnT) implemented with the discrete Fourier transform (DFT). Recent contributions have demonstrated the usefulness of OCDM for optical, underwater acoustics, and sensing applications [17; 18; 19; 20]. Moreover, [PERSON] et al. [21] introduced the orthogonal time-frequency division multiplexing (OTFDM) scheme to reduce the computational complexity of bit and power allocation. The OTFDM is based on the discrete orthogonal Stockwell transform (DOST) [22], which is mostly used in digital image processing with its fast transform application [23; 24]. An analysis of the mathematical descriptions of these schemes shows the existence of relationships among them, which can be exploited to design multi-scheme transceivers for dealing with distinct sets of constraints in PLC systems. Moreover, the literature shows that the HS-OFDM scheme for PLC systems has been widely and deeply investigated. Consequently, it has been introduced in several standards and protocols; however, we cannot say the same for the other aforementioned schemes. Considering the OCDM scheme, the literature shows investigations considering the carrier frequency offset and narrowband interference in wireless systems [25]. Moreover, the authors in [16] compared the HS-OFDM scheme, SCCP, and OCDM sensitivity to the cyclic prefix (CP) length violation based on the Monte Carlo Simulation. Considering the OTFDM schem, [21] introduced and applied it to reduce computational complexity during the resource allocation process while [26] provided an initial discussion about the CP length violation and the symbol timing offset (STO). Unfortunately, the available literature does not show how these schemes, under the presence of the CP length violation, behave when PLC channels are corrupted by white or colored additive noises, and different techniques are applied to perform resource allocation and frequency domain equalization.