A New Ultracompact Narrow Bandpass Microstrip Filter Using Double-Negative Quasiplanar Cells

Table 2

Comparison between the proposed filter and some other compact narrow BPFs reported in the literature (sorted by their size in the descending order).

Reference	Resonator	f0 (GHz)	FBW (%)	Size [λ0 × λ0]	IL (dB)	No. of metal layers	εr of the substrates
[11]	SRR	4.6	1.7	0.46 × 0.23	5.2	2	2.2
[22]	CSRR	4.9	4	0.41 × 0.16	2.8	2	2.2
[13]	SRR	0.9	2.9	0.25 × 0.07	5.1	3	10.2
[16]	EBG	5	3.7	0.23 × 0.08	2.8	2	10.2
[14]	CRLH-CPW	5	6	0.2 × 0.08	2.5	2	10.2
[23]	Loaded stub	2.4	3.5	0.2 × 0.17	2.3	2	3.5
[24]	SI-CSRR	8.4	7.9	0.2 × 0.1	1.5	2	2.2
[25]	Square SRR	2.4	12.1	0.18 × 0.07	0.3	2	10.2
[12]	S-shaped SRR	1.25	12	0.18 × 0.04	2.4	2	10.2
[15]	SI resonator	2.4	10.8	0.16 × 0.16	5.8	2	4.5
[10]	CSRR	1	8	0.16 × 0.07	1.5	2	10.2
This work	BC-SR	1	2.2	0.11 × 0.04	4.2	4	3.5