A Novel Band-Stop Filter with Band-Pass, High-Pass, and Low-Pass Negative Group Delay Characteristics

Table 10

Performance comparison between band-pass negative group delay in the passband of the band-stop filter and the proposed NGD band-stop filter.

Literature	f0 (GHz)	NGD (ns)	NGD band (MHz)	IL (dB)	FOM
[29]	1.962	−7.3	100	22.65	0.0511
[30]	1.99	−6.5	105	22.6	0.0477
[31]	2.14	−1.0	60	3.8	0.0384
[32]	1.0	−1.5	370	33	0.0111
[33]	2.14	−0.034	—	6.05	—
This work	0.0210	−6.03	15.83	3.5	0.0639

f₀ refers to the frequency at the minimum negative group delay. NGD (ns) refers to the minimum negative group delay. IL is the insertion loss.