高频电子线路课后习题答案(第五版)张肃文(8)

4 17解：L1

11

118 μH 223 12ω0C12π 465 10 1000 10

118118118

L36 L2 L34 L56 60 13.5 120

737373

C12 C1 Co 1000 4 1004 pF

13.5

C36 C2 pCi 1000 40 1004 pF

74.5

ω0C12π 465 103 1000 10 12 6

g12 go 20 10 49 μS

Q0100

22

2

ω0C2 13.5 2π 465 103 1000 10 12 3

g36 pgi 49 μS 0.62 10

Q0100 74.5

初、次级回路参数相等。若为临界耦合，即 1，则

13.5 31 40 10p1p2yfe

Avo 74

g2 49 10 6

22

2

ω0C122π 465 103 1004 10 12

QL 60 6

g1249 102Δf0.7

f0465 103 2 2 10.9 kHZ

QL60

Kr0.1 3.16

2

4 20解:vn 4kTRΔfn 4 1.38 10 23 290 1000 107 12.65 μV

2

in 4kTGΔfn 4 1.38 10 23 290 10-3 107 12.65 nA

2222

4 21解： vn vn1 vn2 vn3 4kT1R1Δfn 4kT2R2Δfn 4kT3R3Δfn

4k T1R1 T2R2 T3R3 Δfn 4kT R1 R2 R3 Δfn T

T1R1 T2R2 T3R3

R1 R2 R3

2222

又 in in1 in2 in3 4kT1G1Δfn 4kT2G2Δfn 4kT3G3Δfn

4k T1G1 T2G2 T3G3 Δfn 4kT G1 G2 G3 Δfn T

T1G1 T2G2 T3G3R1R2T3 R2R3T1 R3R1T2

G1 G2 G3R1R2 R2R3 R3R1