On Narrowband Interference Suppression in TDCS with WFRFT Preprocessing

Table 1

Comparisons between different NBI suppression methods.

Methods	Classification	Prior info. (Y/N)	Iterative procedure (Y/N)	Suppression effects	Mains ideas and representative Refs
Successive interference cancellation	Subtraction	N	Y	A	Successive cancellation [19] / Cancellation with soft decision [20]
Compressive Sense	Subtraction	Almost Y	Y	A	A structured dictionary Mismatch formulation [21]/Sparse high-dimensional NBI reconstruction [22]
Sparsity-Aware approach/mitigation based on CS	Subtraction	N	Y	A	Inherent sparsity of NBI [23]/Mitigating spectral leakage to the best [24]
Block sparse Bayesian learning	Subtraction	N	Y	A	Intra-block correlation (IBC) [25]
Equalization	Avoidance	N	N	B	Linear precoding [26]Maximum SNR optimization [27]/Widely linear-zero force [28]/Optimal rank reduction [29]
Time/frequency filter	Avoidance	N	N	B	Excision filtering [30]
Spread spectrum	Transform process	N	N	C	Carrier interferometry spreading codes [31]
Wavelet process	Transform process	N	N	C	Wavelet domain spectral periodogram [32]
Frequency domain process	Transform process	N	N	C	Spectral shaping [33]/Autoregressive estimator to get PSD [34]