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

Table 9

Comparison results of theory, simulation, and measurement.

Comparison	f0 (MHz)	NGD (ns)	f (MHz)	GD (ns)	ILf0 (dB)	ILf (dB)
Theo.	21.3	−5.9	102.3	20.0	3.5	27.2
Simu.	21.3	−3.9	100.3	−30.4	3.3	11.8
Mear.	21.3	−3.1	100.3	−47.2	3.1	14.5

f₀ is the frequency at which the minimum negative group delay occurs in the passband of the band-stop filter. NGD represents the minimum negative group delay at frequency f₀. f represents the resonant frequency of the band-stop filter. GD represents the group delay at frequency f. IL_f0 represents the insertion loss at frequency f₀. IL_f represents the insertion loss at frequency f.