figs08 2nd edition - Academics |...

42
R. Ludwig and G. Bogdanov “RF Circuit Design: Theory and Applications” 2 nd edition Figures for Chapter 8 Figure 8-1 Eight possible configurations of discrete two-component matching networks. L L C C (a) (b) (c) (d) Z S Z L Z S Z L Z S Z L Z S Z L C 1 C 2 L C C (e) (f) (g) (h) L 2 L 1 Z S Z L Z L Z S L 2 L 1 Z S L Z L Z L C 2 C 1 Z S

Transcript of figs08 2nd edition - Academics |...

R. Ludwig and G. Bogdanov“RF Circuit Design: Theory and Applications”

2nd edition

Figures for Chapter 8

Figure 8-1 Eight possible configurations of discrete two-component matching networks.

L L

C C

(a) (b) (c) (d)

ZS ZL ZS ZL ZS ZL ZS ZL

C1C2

L

C C

(e) (f) (g) (h)

L2

L1ZS ZL ZLZS L2

L1

ZS

L

ZL ZL

C2C1

ZS

Figure 8-2 Transmitter to antenna matching circuit design.

L

CTransmitter

ZM

ZAZT

Figure 8-3 Impedance effect of series and shunt connections of L and C to a complex load in the Smith Chart.

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Shunt L

Series C

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Shunt C

Figure 8-4 Design of the two-element matching network as part of the ZY Smith Chart.

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L

CC

ZT

ZT

ZT

zTC = 12j1.22

zT = 21j1

zM = zA* = 12j0.2

Figure 8-5 Design of a matching network using the Smith Chart

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zL*

A D

B C

zS

Figure 8-6 Matching networks for four different paths in the Smith Chart.

→ →zS zA zL*

L1 = 1.59 nH

L2 = 6.63 nHZS ZL 2.23 pF

6.37 nH

ZS ZL

→ →zS zB zL*

0.94 pF

3.06 nH

→ →zS zC zL*

ZS ZL

2.79 nH

13.26 nHZS ZL

→ →zS zD zL*

Fig

ure

8-7

For

bidd

en r

egio

ns fo

r L-

type

mat

chin

g ne

twor

ks w

ith Z

S =

Z0

= 5

0 Ω

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(a)

(c)

(b)

(d)

ZS

ZL

ZS

ZL

ZS

ZL

ZS

ZL

Figure 8-8 Two design realizations of an L-type matching network.

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zS

A

B

zL

(b)

RS = 50 Ω C = 2.6 pF CL Vout

L = 10 nH

VS

RL

(c)

VS

RS = 50 Ω L = 9.75 nH

C = 0.6 pF

CLVout

RL

(a) Impedance transformations displayed in Smith Chart

Figure 8-9 Frequency response of the two matching network realizations.

Frequency f, GHz

Circuit in

Figure 8-8(b)

Circuit in

Figure 8-8(c)

00

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(a) Frequency response of input reflection coefficient

Inp

ut

refl

ecti

on

co

effi

cien

t |Γ

in|

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(b) Transfer function of the matching networks

Circuit in

Figure 8-8(b)

Circuit in

Figure 8-8(c)

Tra

nsf

er f

un

ctio

n H

, d

B

Frequency f, GHz

Figure 8-10 Comparison of the frequency response of the L-type matching network and an equivalent bandpass filter.

(a) Equivalent bandpass filter

RST = 125.1 Ω

Vb

VTCT

1.55 pF

LLN

16.2 nHRLP = 125.1 Ω

Frequency f, GHz

Equivalentfilter

Circuit inFigure 8-8(c)

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(b) Frequency response of the matching network compared to the equivalent

filter response

Tra

nsf

er f

un

ctio

n H

, d

B

Figure 8-11 Constant Qn contours displayed in the Smith Chart.

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Qn = 3

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Qn = 0.3

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Qn = 1

Qn = 3

Qn = 10

Figure 8-12 Two L-type matching networks for a 50 source and a load impedance operated at a frequency of 1 GHz.

(a) Impedance transformation in the Smith Chart

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A Qn = 1

Qn = 1

zL

Resulting matching networks

(b)

RS = 50 Ω L = 0.8 nH

VS

C = 3.18 pF RL

LL = 3.18 nH Vout

(c)

VS

RS = 50 Ω C = 3.54 pF LL = 3.18 nH

RL

Vout

L = 7.96 nH

Ω ZL 25 j20+( )Ω=

Figure 8-13 Frequency responses for the two matching networks.

3 dB

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Figure 8-12(c)

Figure 8-12(b)

4

Tra

nsf

er f

un

ctio

n H

= V

ou

t/ V

S,

dB

Frequency f, GHz

Figure 8-14 General topology of a T-type matching network.

Z3 Z1

ZL

ZA

Z2

ZBZin

Figure 8-15 Design of a T-type matching network for a specified Qn = 3.

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A

zin

Qn = 3

zL

Figure 8-16 T-type matching network circuit schematics.

L3 = 7.85 nH C1 = 8.72 pF

C2 = 3.53 pF ZL

Zin

Figure 8-17 Design of a Pi-type matching network using a minimal Qn.

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B

A

zin Qn = 2

Qn = 2

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Figure 8-18 Pi-type matching network configuration.

C2 = 1.65 pF

ZLL1

1.31 nH

L3

1.66 nH

Zin

Figure 8-19 Mixed design of matching network involving transmission line sections (TL) and discrete capacitive elements.

ZL

TL3 TL2 TL1

C2 C1

Zin

Figure 8-20 Design of the distributed matching network for Example 8-7.

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40-40

50

-50

60

-60

70

-70

80

-80

90

-90

100

-100

110

-110

120

-120

130

-130

140

-140

150

-150

160

-160

170

-170

18

0

0.0

1

0.0

1

0.0

2

0.0

2

0.0

3

0.0

3

0.04

0.04

0.05

0.05

0.06

0.06

0.07

0.07

0.08

0.08

0.09

0.09

0.1

0.1

0.11

0.11

0.12

0.12

0.13

0.13

0.14

0.14

0.15

0.15

0.16

0.16

0.17

0.17

0.18

0.18

0.19

0.19

0.2

0.20.21

0.210.2

2

0.2

20.2

3

0.2

3

0.2

4

0.2

4

0.2

5

0.2

5

0.2

6

0.2

6

0.2

7

0.2

7

0.2

8

0.2

8

0.29

0.29

0.3

0.3

0.31

0.31

0.32

0.32

0.33

0.33

0.34

0.34

0.35

0.35

0.36

0.36

0.37

0.37

0.38

0.38

0.39

0.39

0.4

0.4

0.41

0.41

0.42

0.42

0.43

0.43

0.44

0.44

0.45

0.45

0.46

0.46

0.4

7

0.4

70.4

8

0.4

8

0.4

9

0.4

9

0.0

0.0

zin

A

B

l2 = 0.26

l 1 =

0.055

zL

Figure 8-21 Matching network combining series transmission lines and shunt capacitance.

l2 = 0.26 l1 = 0.055

ZL

Zin

C1 = 4.37 pF

Figure 8-22 Input impedance as a function of the position of the shunt capacitor in Example 8-7.

Distance l,

No

rmal

ized

in

pu

t re

acta

nce

, x i

n

xin

rin

0 0.05 0.1 0.15 0.2 0.25 0.3 0.35

3.5

3

2.5

2

1.5

0.5

1

2

1.5

1

0.5

0

20.5

21

No

rmal

ized

in

pu

t re

sist

ance

, r i

n

l = l1

Figure 8-23 Two topologies of single-stub matching networks.

Open or

short circuitOpen or

short circuit

(a) (b)

Z0L, lL

Zin

Z0S

lSZL

Z0L, lL

ZLZ0S

lSZin

Figure 8-24 Smith Chart design for the single-stub matching network based on Example 8-8.

0.2

0.2

0.2

0.50.5

0.5

1.0

1.0

1.0

2.02.0

2.0

5.0

5.0

5.0

0.5

0.5

0.5

0.5

2.02.0

2.0

2.0

0.2

0.2

0.2

0.5

0.5

0.5

1.0

1.0

1.0

2.0

2.0

2.0

5.0

5.0

5.0

0.5

0.5

0.5

0.5

2.0

2.0

2.0

2.0

0.2

0.2

0.2

0.50.5

0.5

1.0

1.0

1.0

2.02.0

2.0

5.0

5.0

5.0

0.5

0.5

0.5

0.5

2.02.0

2.0

2.0

0010

-10

20

-20

30-30

40-40

50

-50

60

-60

70

-70

80

-80

90

-90

100

-100

110

-110

120

-120

130

-130

140

-140

150

-150

160

-160

170

-170

18

0

0.0

1

0.0

1

0.0

2

0.0

2

0.0

3

0.0

3

0.04

0.04

0.05

0.05

0.06

0.06

0.07

0.07

0.08

0.08

0.09

0.09

0.1

0.1

0.11

0.11

0.12

0.12

0.13

0.13

0.14

0.14

0.15

0.15

0.16

0.16

0.17

0.17

0.18

0.18

0.19

0.19

0.2

0.20.21

0.210.2

2

0.2

20.2

3

0.2

3

0.2

4

0.2

4

0.2

5

0.2

5

0.2

6

0.2

6

0.2

7

0.2

7

0.2

8

0.2

8

0.29

0.29

0.3

0.3

0.31

0.310.32

0.32

0.33

0.33

0.34

0.34

0.35

0.35

0.36

0.36

0.37

0.37

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0.38

0.39

0.39

0.4

0.4

0.41

0.41

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0.42

0.43

0.43

0.44

0.44

0.45

0.45

0.46

0.46

0.4

7

0.4

70.4

8

0.4

8

0.4

9

0.4

9

0.0

0.0

zL

A

B

l SA

= 0

.067

zin

l LA

= 0

.266

Figure 8-25 Balanced stub design for Example 8-9.

0.25

ST2

TL1

ZLZin ST10

.32

4

Z0S = 107.1 Ω Z0L = 86.6 Ω

0.3

24

Figure 8-26 Double-stub matching network arrangement.

Zin = Z0 ZA ZB ZC ZD

l3 l2 l1

ZLlS1lS2

Open or

short circuit

Figure 8-27 Smith Chart analysis of a double-stub matching network shown in Figure 26.

0.2

0.2

0.2

0.50.5

0.5

1.0

1.0

1.0

2.02.0

2.0

5.0

5.0

5.0

0.5

0.5

0.5

0.5

2.02.0

2.0

2.0

0.2

0.2

0.2

0.5

0.5

0.5

1.0

1.0

1.0

2.0

2.0

2.0

5.0

5.05

.0

0.5

0.5

0.5

0.5

2.0

2.0

2.0

2.0

0.2

0.2

0.2

0.50.5

0.5

1.0

1.0

1.0

2.02.0

2.0

5.0

5.0

5.0

0.5

0.5

0.5

0.5

2.02.0

2.0

2.0

g = 2 circle

Forbidden

region

yB circle (g = 1) 3 /8

yC circle

(3 /8 rotated g = 1 circle)

Figure 8-28 Double-stub matching network design for Example 8-10.

0.2

0.2

0.2

0.50.5

0.5

1.0

1.0

1.0

2.02.0

2.0

5.0

5.0

5.0

0.5

0.5

0.5

0.5

2.02.0

2.0

2.0

0.2

0.2

0.2

0.5

0.5

0.5

1.0

1.0

1.0

2.0

2.0

2.0

5.0

5.0

5.0

0.5

0.5

0.5

0.5

2.0

2.0

2.0

2.0

0.2

0.2

0.2

0.50.5

0.5

1.0

1.0

1.0

2.02.0

2.0

5.0

5.0

5.0

0.5

0.5

0.5

0.5

2.02.0

2.0

2.0

yB

yC

yL

yD

yA

Forbidden

region

3 /8

Figure 8-29 Various classes of amplifier operation.

Output waveform

(a) Class A (b) Class B

(c) Class AB (d) Class C

IC

Linear regionIdeal transfer

function

Quiescent

point

V* VBE

Cutoff region

Input waveform

IC

Quiescent

pointVBE

ΘB = 180˚

Quiescent

point

IC

VBE

IC

Quiescent

point

VBE

Figure 8-30 Load and power supply current waveforms as a function of conduction angle.

(a) Load current waveform at the output of the transistor

0 Θ6π

IL

I0

Θ0

(b) Corresponding power supply current waveform

0

Θ0

Θ4π 6π

IS

IQ + I0

IQ

Θ0/2

Figure 8-31 Maximum theoretical efficiency of an ideal amplifier as a function of conduc-tion angle.

Eff

icie

ncy

,

% = 78.5%Class B

Class AB

Class C

0 5050

55

60

65

70

75

80

85

90

95

100

100

150 200 250 300 350

Class A

Conduction angle, Θ0

Θ0 = 180˚

Figure 8-32 Passive biasing networks for an RF BJT in common-emitter configuration.

(a)

RFC

RFoutRFC

VCC

R1

CB

I1IB

IC

CB

RFin

R2

(b)

RFC

RFCIX

CB

VCC

IC

IB

RFout

RFin

R3

CBR1

VX

R2

R4

Figure 8-33 Active biasing network for a common-emitter RF BJT.

RFC

RFin

RFout

RFC

I1

Q2

Q1

IB1IC1

VC1

IB2

VCC

CB

CB

RB1

RB2

RC1

IC2

RC2

Figure 8-34 Active biasing network containing low-frequency transistor and two diodes.

RFC

RFC

RFin

RFout

R1

D1

Q1

Q2

D2

R2

VCC

CB

CB

Figure 8-35 Modification of the active biasing network shown in Figure 33 for common-base RF operation.

RFC

RFC

RFC

RFin

RFout

Q1

Q2

I1

VCC

CB

CB

RC1

RC2

RB2

IC1

IC2

IB1

IB2

VC1

RB1

Figure 8-36 DC and RF equivalent circuits for the active biasing network in Figure 35.

RFC

RFC

RFC

RFC

RFC

RFC

(a) DC equivalent circuit (b) RF equivalent circuit

RFin

RFout

Q2

Q1

Q2

Q1

VCCVCC

CB

CB

CB

CB

RC2

RC1RB1

RB2RB2

RC1 RB1

RC2

Figure 8-37 Bipolar passive biasing network for FETs.

RFC RFC

RFin

RFout

CB

VDVG

CB

Figure 8-38 Unipolar passive biasing networks for FETs.

RFC

RFCRFC

RFC

RFC

RFinRFin

RFoutRFout

RS

VD

CB

CB

VS

CB

VD

CB

Figure 8-39 E-pHEMT biasing network: (a) DC bias circuit, (b) DC model, (c) low-frequency small-signal model.

(b) (c)

(a)

R2R1

R3 R4

X1

Q2Q1

VDDVDD

VD

ID

VG

IR3

R2R1

+ +

– –

R3 R4

X1

VDD VDD

VD

VG

|VBE1| |VBE2|IB2IB1

IB1

ID

IR3

R2R1

R3

re1 re2

R4

id

vg

ib2ib1

iB1 iB2IB2

Figure 8-40 Conceptual PCB layout of the 7 GHz amplifier, showing the biasing filters and matching networks implemented with microstrips.

ATF551M4

/4

L1 L2

S1 S2

ΓMS

ΓML

VDS

RFin

CB

VGS

CB CB

RFout

CB

/4

Figure 8-41 Schematic of the designed 7 GHz amplifier including the PCB substrate de-scription and the S-parameter simulation setup.

RR1R = 5.90 kOhm

RR2R = 5.11 kOhm

CC2C = 270 pF

CC4C = 270 pF

CC3C = 270 pF

CC1 C = 270 pF

MLINTL1Subst = “MSub1”W = 43.4 milL = 254.9 mil

MLINTL3Subst = “MSub1”W = 43.4 milL = 254.9 mil

MLINTL4Subst = “MSub1”W = 43.4 milL = 191 mil

V_DCSRC 1 Vdc = 5.0 V

VIAFCV1D = 15.0 milH = 20.0 milT = 0.5 mil

VIAFCV3D = 15.0 milH = 20.0 milT = 0.5 mil

VIAFCV4D = 15.0 milH = 20.0 milT = 0.5 mil

S-PARAMETERSMSub

S_ParamSP1Start = 0.1 GHzStop = 10 GHzStep = 0.01 GHzCalcNoise = yas

MSUBMSub1H = 20.0 milEr = 3.48Mur = 1Cond = 5.8E + 7T = 1.4 milTanD = 0.0031

MLOCTL2Subst = "MSub1"W = 43.4 milL = 199 mil

MLOCTL5Subst = "MSub1"W = 43.4 milL = 169 mil

Display Templatedistemp2“S_Params_Quad_dB_Smith”“S_21_11_wZoom”

DispTemp

Display Templatedistemp3 “Circles_Ga_NF”“Circles_Stability”

DispTemp

ATF551M4X1

ATF551M4

G S2

S1 D

VIAFCV2 D = 15.0 milH = 20.0 milT = 0.5 mil

TermTerm 1Num = 1Z = 50 Ohm

+

RR3 R = 20 kOhm

RR4R = 100 Ohm

ap_pnp_2N3906_19930601Q1

ap_pnp_2N3906_19930601Q2

+

TermTerm 2Num = 2Z = 50 Ohm

+

OPTIONS

OptionsOptions 1Temp = 16.85 Tnom = 25 Topology check = yesV_RelTol = 1e-6l_RelTol = 1e-6GiveAllWarnings = yesMaxWarnings = 10

Figure 8-42 Simulated S-parameters of 7 GHz amplifier.

Input Reflection Coefficient

Output Reflection Coefficient

Reverse Transmission, dB

Forward Transmission, dB

m2

freq = 7.000 GHz

S(1, 1) = 0.079 / –172.251

impedance = Z0 * (0.855 – j0.018)

0

6.0 6.5 7.0 7.5 8.0

0 1 2 3 4 5 6 7 8 9 10

dB

(S(1

, 1))

dB

(S(2

, 1))

dB

(S(2

, 2))

dB

(S(1

, 2))

–5

30

20

10

0

–10

–20

–30

–40

–50

–60

freq, GHz

6.0 6.5 7.0 7.5 8.0

freq, GHz

freq, GHz

0 1 2 3 4 5 6 7 8 9 10

freq, GHz

–10

–10

–20

–30

–40

–50

–60

–70

–15

–20

0

–10

–20

–30

–40

–25

m2

S(1

, 1)

S(2

, 2)

freq(100.0 MHz to 10.00 GHz)

freq(100.0 MHz to 10.00 GHz)

m5

m4

m3

m3

freq = 7.000 GHz

S(2, 2) = 0.023 / 93.824

impedance = Z0 * (0.996 + j0.045)

m5

freq = 7.000 GHz

dB(S(1, 2)) = –17.928

m4

freq = 7.000 GHz

dB(S(2, 1)) = 13.777

freq[690] S[690](1, 1) S[690](1, 2) S[690](2, 1) S[690](2, 2)

0.023 / 93.8244.885 / –129.2860.127 / –143.7300.079 / –172.2517.000 GHz