CST中算出的偶合系數(shù)怎么這么大?
Tchebychev Filter
===================
Order = 4
Bandwidth = 8 MHz
Passband ripple = 0.01 dB (1.100747 VSWR)
Return loss = -26.3828 dB
Normed g values:
-------------------------------------------
g1 = 0.7129
g2 = 1.2004
g3 = 1.3213
g4 = 0.6476
g5 = 1.1008
Corresponding coupling coefficients in MHz:
-------------------------------------------
k_E = 11.22
k1_2 = 8.65
k2_3 = 6.35
k3_4 = 8.65
k_out = 11.22
Group Delay Time
----------------
t_d1 = 56.727 ns
t_d2 = 95.519 ns
t_d3 = 161.87 ns
t_d4 = 147.054 ns
t_d5 = 224.313 ns
你檢查哈,結(jié)果第一個本征模的諧振頻率是不是0哦?
我以前就出現(xiàn)過耦合系數(shù)大于1的情況,仔細(xì)看原來是諧振頻率不對
簡易你多加幾個模式計算
或者用HFSS
非常感謝指點(diǎn)上面數(shù)據(jù)是由后處理模板直接算出的,是歸一化的嗎?
Corresponding coupling coefficients in MHz:
-------------------------------------------
k_E = 11.22
k1_2= 8.65
k2_3= 6.35
k3_4= 8.65
k_out = 11.22
用上面的值處以中心頻率就是所需要的耦合系數(shù)了