Novel Gysel Power Dividers with Negative Group Delay Characteristics

Table 2

Performance comparison.

Ref.	f0 (GHz)	NGD (ns)	NGD bandwidth (MHz)	IL (dB)	IL bandwidth (MHz)	RL (dB)	Isolation (dB)	FOM (10^−3)	Size ( × )
[9]	1.00	−1.10	250^#	22.7	173	25.0	23.0	3.43	0.55 × 0.04
[10]	2.14	−0.53	150	24.4	250	20.6	42.2	0.56	0.50 × 0.50
[11]	2.14	−0.48	450	18.1	300	19.9	38.9	3.56	0.62 × 0.34
[12]	2.14	−0.48	540^+	15.0	410	37.0	34.9	8.88	0.61 × 0.76
[13]	2.14	−1.16	100	9.29	150	26.8	42.2	2.79	0.55 × 0.58
[14]	2.14	−0.56	55	6.97	100	17.5	15.8	0.62	0.94 × 0.48
[15]	2.14	−0.20	310	14.0	550	32.5	1.2	3.18	0.65 × 0.34
This work	1.00	−1.97	31.3	8.29	155	38.3	41.2	3.68	0.40 × 0.39

Only one output port having NGD characteristics. ^#Results for two-section directional couplers. ⁺Results for the example A in [12].