EXP NO:4 DATE: 12-2-2016

4. 90˚COUPLER(BRANCH LINE COUPLER)AIM:- The main aim of the task is to verify the properties of the 4-port transmission network

TOOL USED:

AWR microwave software

SPECIFICATIONS:

Er=4.4

T=0.05mm

H=0.8mm

f=3.2GHz

Tand=0.002

Zo=50 ohm

TABULATION:

CIRCUIT:

impedance Electrical length(deg) W(mm) L(mm)

Z0/√2 90 2.55932 12.5331

Z0 90 1.4786 12.9835

Z0/√2 90 2.55932 12.5331

Z0 90 1.4786 12.9835

GRAPHS FOR CHECKING RECIPROCITY:

ANGLE PLOT:

Calculations:-S11

2+S212+S31

2+S412=0.98569(values are taken from tables above)

At f=3.2GHz,

Isolation=20log|1/S41|=-48.635db

Directivity=20log|S31/S41|=-45.563db

Coupling=-20log|S31|=-3.072db

Return loss=-20log|S11|=-49.121db

Result:-1) Reciprocal:-S12=S21, S13=S31, S23=S32, S24=S42, S34=S43

2) Matched:-S11=S22=S33=S44

3) Lossless:-S112+S12

2+S132+S14

2=0.98569

4) Phase difference at f=3.2 GHz:-

˂S21˚= -89.939˚, <S31˚= -179.92˚

˂S21 - <S31˚= 900

Thus different properties are successfully verified.