Design Optimization of Feeding Networks with a Special Size for Self-Interference Cancellation

Table 1

Comparison of currently proposed interference-reduction techniques.

Reference number	Decoupling scheme	Form of the SIC FN	Self-interference symmetry	Occupy extra space
[8–13]	Block structures	—	—	Yes
[15–18]	Decoupling network	—	—	Yes
[20]	Decoupling superstrate	—	—	Yes
[21]	SIC FN	Differential feeding	Symmetry	No
[22, 23]	SIC FN	Pairwise antiphased feeding	Symmetry	No
[24]	SIC FN	Butler matrix beamforming networks	Symmetry	No
This letter	SIC FN	Customize the size according to the antenna	No limit	No