1,,,,, UHF ( 300MHz, 1m ),?, 1MHz 300m FR-4 137m cm, 1MHz,, 1GHz? 1MHz 1/1000 30cm, FR-4 137cm cm,,,, W, dbm(0dbm=1mw)
2 S Parameter(Scattering Parameter), Y Parameter, Smith Chart S Parameter S21 S11 S22 a1 :, b1 : a2 :, b2 : < S Parameter > 1) S11 : (ZL=Zo, a2=0) S11 = b1/a1 2) S12 : (Zs=Zo, a1=0) S12 = b1/a2 3) S21 : (ZL=Zo, a2=0) S21 = b2/a1 4) S22 : (Zs=Zo, a1=0) S22 = b2/a2 b1 = S11 a1 + S12 a2 b2 = S21 a1 + S22 a2 S12 - b1( ) a1( a2( ) 4, b2( ) a1( ) 4, a2 ( ) - S Parameter * (Pi)= I a1 I 2 * (Pir) = I b1 I 2 * (Po)= I a2 I 2 * (Por) = I b2 I 2
4 1-1' (P1) P1= Pi - Pir = I a1 I 2 - I b1 I 2 = I a1 I 2 - I S11a1 + S12a2 I 2 = I a1 I 2 - I a1 I 2 * I S11 I 2 ; a2=0 : 2-2' (P2) P2= Po-Por = I a1 I 2 * I S21 I 2 (Gp : Power Gain) Gp= 10 log (P2/P1) = 10 log I S21 I 2 1- I S11 I 2 (Gu : Unilaterial Gain) Gu = 10 log I S21 I 2 = 20 log I S21 I [db] Smith Chart? 1939 Philip F Smith transmission line,,, Smith Chart ZL, R,
Y Parameter <Parameter > - h Parameter y Parameter, S Parameter Y Parameter or S Parameter * ( ), ( ) * * FET Y Parameter 1) Y Parameter i1 = yi v1 + yr v2 i2 = yf v1 + yo v2 ( y Parameter FET I, r, f, o e, b, s ) [S], * yi ( )=i1 / v1 (v2=0, 2-2 ) * yr ( )=i1 / v2 (v1=0, 1-1 ) * yf ( )=i2 / v1 (v2=0) * yo ( )=i2 / v2 1 v1 1 i1 y11 y21 y12 y22 i2 2 v1 2 (v1=0) 4 Parameter, y=g +jb ( + ) y=g +iwc ( + ) Or y= y e j ( + ) ( y = (g 2 + b 2 )
* gi : 1/gi ri ri, FET K * Ci :, * yr :, * yf :, FET gm( ) * go :, 1/go= ro,, FET 1K - K * Co :, Co Cob <Y Parameter > MAG=10Log ( yf 2 /4gigo)dB Gps( ) Gps = S * MAG (S :, 1 ) = 2/(1+cos( r + f)) * gigo / yr yf * yf 2 /4gigo
3, 25 10nH ( 4), ( 5), ( 6), 7,,, 8 10,,, 11 13 15 50 [ 7] [ 8] (25, 50, 75 )
[ 9] (20nH) [ 10] (3PF) [ 12] (500?) [ 13] (10mH
[ 14] (6pF) [ 15] (50, 45, 90 )
4? 1) 25 10nH,,,,,, 1GHz 2 2-1, +, resistance 1, ( ) 2-1 +, 1,
+, 1, (50 )+, 1, (50 )+, 1,
2) 2 10 10nH 1GHz 1GHz Zin=10+j628 50 Z=02+j126, Y=012-j078 +, 2-7 Z, Y Z, Y Y, Y, ( ) 045, C=045/50/2 f=142pf,, Z=10+j0, Y=10+j0, Z, Y Z, ( ) 266, C=1/(2 f 266 50)=120pF
+,, Z, Y, C=1/(2 f 166 50)=192pF L=1/(2 f 200/50)=398nH +,,, Z, Y, C=111/50/2 f=352pf L=266 50/2 f=212nh
(50 )+ 02+j126 (A), 76, A ( ),, 31, 45 1/2, =(76-31)/2=225, C=1/(2 f 333 50)=096pF (50 )+ 2-11
5 Transistor uv Bipolar Transistor, [NF] 6dB/oct : -3dB/oct : FL Log f fn =f (1- ), NF f Tr STC918K NF [STC918K NF vs f ] [STC918K NF vs Ic ] NF vs f NF NF vs Ic NF, Gain NF, Gain Bias Point
FET (Field Effect Transistor) - FET NF, FET,, FET NF NF = 10 Log { 1+gi/gs + Rn/gs(gs+gi) 2 } * gi : ; Unit : [db] * gs: ( ) * Rn :, NF (gs) OPT NF/ gs = 0, (gs) OPT = {gi(gi + 1/Rn)} ; (gi) OPT > gi MAG(Maximum Available Gain), gs=gi NF (gi) OPT > gi, NF gs MAG gs * gs=gi NF = 10 Log (2 + 4 Rngi), Rn=0, NF NF = 10 Log2 = 3dB 3dB NF 3dB gs > gi
6 IMD (Intermodulation Distortion) Bipolar Transistor IMD FET, io ei io=io + Aei + Be 2 i + Ce 3 i ; 3 2 * : ei = cosw1t + cosw2t io io=io + B/2 ( 2 + 2) + [A + 2C 3 /4 + 3C 2 ]cosw1t + [A + 3C 2 /2 + 3C 3 ]cosw2t + B 2 cosw2w1t + B 2 /2cos2w2t + B cos(w1 w2)t 2 3 + C 3 /4osw3w1t + C 3 /4cos3w2t + C 2 /4cos(2w1 w2)t + C 2 /4cos(2w1 w2)t 2 2, 3 3 Amplitude 2f -f f f 2f -f 1 2 1 2 2 1 Frequency 2,, 2, 3, 3 1:2, 1:3 2w1 w2, 2w2 w1(3 ) w1, w2 Spurious Filter 3 Distrotion
2, 3 (, ) 2, 3?? FET IMD FET Drain Id Vg Id = Idss [ 1 + Vg/Vp ] 2 * Idss :, Vp : Vg 3 FET 3 Bipolar Transistor FET,