Fully Distributed Tunable Bandpass Filter Based on Ba_𝟎.𝟓Sr_𝟎.𝟓TiO_𝟑 Thin-Film Slow-Wave Structure

Table 2

Comparison of the tested Fishbone filters with other microwave ferroelectric bandpass filters operating at room temperature (localized-element architecture on [10–16] and fully distributed architecture below [17–19]).

Ref.	f0 (GHz)	Bias (V)	E (V·μm^−1)	Frequency tunability	Bandwidth @ −3 dB (%)	Insertion loss (dB)	Q factor	FoM (dB^−1)	FoM per kV bias
[10]	2.44	200	40	18%	24.6–31.3	5.1–3.3	10	0.14	0.7
[11]	8.35	30	20	6%	7.8–7.8	5.7–3.5	33	0.16	5.6
[12]	10.04	20	13.3	7.4%	19.9–23.2	2.9–1.95	20	0.14	7.0
[13]	8.75	100	20	25.3%	19.4–15.5	4–8	12	0.23	2.3
	11.7	100	20	22.2%	12–14	6–10	14	0.20	2.0
[14]	11.5	30	20	21.7%	15.7–15.9	5.4–3.3	17	0.29	9.9
[15]	19.86	400	8	9.1%	3.5–3.2	3.5–3.5	89	0.73	1.8
[16]	29	30	20	17.2%	15.5–15.5	6.9–2.5	17	0.23	7.8
[17]	2.7	200	8	29.6%	9.3–8.6	25.7–14.3	13	0.15	0.8
[18]	4.4	150	15	7.7%	2.6–2.4	14.8–7.8	57	0.27	1.8
[19]	16.68	100	4	2.9%	7.6–9.5	8.1–5.25	23	0.05	0.5
This work	6.3	30	3	9%	17.9–15.1	6–6.3	12	0.08	2.4
	6.95	30	10	30.2%	23.3–15.8	8.4–9.4	8	0.15	5.2