Advancements in Noise Measurement by Ken Wong, Senior Member IEEE R&D Principal Engineer Component Test Division Agilent Technologies, Inc. Page 1
EuMw Objectives 007 Aerospace Agilent Workshop and Defense Symposium 007 Noise Figure Measurements Y-Factor Cold source Noise Parameters Noise Wave Correcting for Source Impedance Mismatch Correcting for Receiver Mismatch and Noise VNA Noise Figure Measurements Setup (S) Setting Input (Fwd) and Output (Rev) Powers Choosing Noise Bandwidth Setting Noise Averaging Factor Choosing the Receiver Gain Setting Page
EuMw Objectives 007 Aerospace Agilent (cont) Workshop and Defense Symposium 007 Calibration Noise Source Calibration (S) S-parameter Calibration (S) Noise Tuner Calibration (S) Verification Mismatch Line Amp Characteristics Combined S11 Combined Gain Combined Noise Figure Page 3
EuMw The Early 007 Aerospace Days Agilent Workshop and Defense Symposium 007 Page 4
EuMw 007 Aerospace Agilent Workshop and Defense Symposium 007 Agilent s Noise Figure Legacy 340A 1958 8970 1980 8560/90 with NF 1995 8510 1999 SA with NF 00 NFA 000 Page 5
EuMw Definition 007 Aerospace Agilent Workshop and Defense Symposium 007 DEVICE S in N in G a S out N out S = G * S ; N = G * N + N T= T0 ( / ) F (noise factor) = = = 1+ ( / ) * out a in out a in add S N in Nout Nadd S N G N G N out a in a in T= T 0 G a Available Gain, NF (Noise Figure) 10*log 10 (F) db D. Vondran, Noise Figure Measurement: Corrections Related to Match and Gain, Microwave J., pp -38, Mar. 1999 Collantes, J. M., R. D. Pollard, et al. (00). "Effects of DUT mismatch on the noise figure characterization: a comparative analysis of two Y-factor techniques." Instrumentation and Measurement, IEEE Transactions on 51(6): 1150-1156. Page 6
EuMw 007 Aerospace Agilent Workshop and Defense Symposium 007 Definition in Terms of Noise Temperature DEVICE T 0 T e, G a N out 0 N = k* T B; N = G * k* T * B in 0 add a e T 90 K ; B bandwidth k T e -3 Boltzmann's constant = 1.380 6505 10 joule/kelvin effective input noise temperature of device Nout Te F = = 1+ G * N T a in 0 Page 7
EuMw Effective 007 Aerospace Temperature Agilent Workshop and Versus Defense Noise Symposium Figure007 1000.00 100.00 Te (K) 10.00 1.00 0.0 0.5 1.0 1.5.0.5 3.0 3.5 4.0 4.5 5.0 NF (db) Page 8
EuMw 007 Aerospace Agilent Workshop and Defense Symposium 007 Definition In Terms Of Noise Parameters is Ys Noisy two-port is Ys e n i n Noiseless two-port R F = F + Y Y = F + 4R n n opt s min s opt min Gs Z0 1+Γopt 1 Γ Γ Γ ( ) s IRE Subcommittee 7.9 On Noise: Representation Of Noise In Linear Two-ports, Proc. IRE, Vol. 48, Pp. 69-74, Jan. 1960 Page 9
EuMw Noise 007 parameters Aerospace Agilent Definition Workshop and Defense (cont) Symposium 007 R 4 Γ Γ n Rn opt s min s opt min Gs Z0 1+Γopt 1 Γ F = F + Y Y = F + F min minimum noise factor R n noise resistance ( ) s Y opt optimum input admittance Y s = source admittance G s = real part of Y s Γ opt optimum input noise match Z 0 = reference impedance Γ s = source match Page 10
EuMw 007 Aerospace Agilent Workshop and Defense Symposium 007 Noise Source ENR Excess Noise Ratio 346C 10 MHz 6.5 GHz Noise source ENR 10 log T T h c 10 T0 T h = Hot Noise Temperature T c = Cold Noise Temperature T 0 = 90 K T c = T 0 when noise sources are calibrated by reference labs. Page 11
EuMw 007 Aerospace Agilent Workshop and Defense Symposium 007 Y factor Method DEVICE T hot T cold T e, G a Pout P out,hot =kbg a (T hot +T e ) P out,cold =kbg a (T cold +T e ) F Y P T YT = T = P N T T Y * T = = 1+ = 1+ G * N T Y 1 * T a out, hot hot cold e out, cold Y 1 out e hot cold in ( ) 0 0 Assumes ALL Reflections are the same. Fundamentals of RF and Microwave Noise Figure Measurements, Hewlett-Packard Application Note 57-1, Palo Alto, CA July 1983 Page 1
EuMw 007 Aerospace Agilent Workshop and Defense Symposium 007 Actual Y factor Measurement Calibration RECEIVER Receiver Calibration T hot T cold Γ s(hot) Γ s(cold) Γ i(rec) T e(r) G a(r) Nout(R) P out F ( R) Γ s N T T Y* T out ( R) e( R) hot cold = = 1+ = 1+ ( ) G * N T Y 1 * T a( R) in 0 0 Assumes Γ s(hot) = Γ s(cold) Page 13
EuMw 007 Aerospace Agilent Workshop and Defense Symposium 007 Actual Y factor Measurement DEVICE RECEIVER T hot T cold T e(d) G a(d) T e(r) Nout(D) Γ s(hot) Γ Γ i(device) s(cold) Γ o(device) Γ i(rec) G a(r) N out(all) P out Note that F F ( all) Γ s = 1+ ( device) Γ ( all ) F s = F o( device ) T Y* T F hot ( Y ) F ( R) Γ ( R) ( R) Γ s 1* T Γ G cold 0 o( device) a( D) 1 Page 14
EuMw Some 007 Y factor Aerospace Agilent Measurement Workshop and Defense Assumptions Symposium 007 Γ =Γ s( hot) s( cold ) F G o( device ) a( device) = = ( R) Γ ( R) N F N Γ s hot( all) cold ( all) N N hot( R) cold ( R) True only if S 11 and S are <<1 Notes: G a (available gain) is a function of S 11, S and Γ s Γ s source reflection of the incident signal Page 15
EuMw Four Examples 007 Aerospace Agilent Of Workshop Y-Factor and Defense Measurements Symposium 007 What you want for good NF accuracy! Noise source On-wafer environment Noise source 1 3 4 On-wafer multi-instrument (ATE) environment Noise source Automated multi-instrument (ATE) environment Noise source Page 16
EuMw 007 Aerospace Agilent Workshop and Defense Symposium 007 Cold Noise Source Technique G a P N = + P n FDut 1 kt 0 BG a Need to know gain very accurately Ga is a function of of S 11, S and Γ s Page 17
EuMw 007 Aerospace Agilent Workshop and Defense Symposium 007 Cold Noise Figure Cal and Measurement Calibrate kgb = k Gain Bandwidth Phot Pcold kgb = T T P N hot cold T = T cal T ~ 10,000K F r T T 1 hot 0 = T P 0 nhot P ncold 1 Measure T = T meas DUT Γ s Γ o(device) Γ i(rec) Γ i(device) 1 P N P n FDut = Fr 1 G + a kgb Page 18
EuMw Noise 007 Parameters Aerospace Agilent Workshop and Defense Symposium 007 is Ys e n i n Noiseless two-port F = F min + 4R Z o n 1+ Γ Γ opt opt Γ s ( ) 1 Γ s Noise figure varies as a function of source impedance Four noise parameters: F min, R n, Γ opt (mag), Γ opt (phase) Page 19
EuMw Noise 007 parameters Aerospace Agilent Definition Workshop and Defense Symposium 007 R F = F + Y Y = F + 4R n n opt s min s opt min Gs Z0 1+Γopt 1 Γ Γ Γ ( ) s F min minimum noise factor R n noise resistance Y opt optimum input admittance Y s = source admittance G s = real part of Y s Γ opt optimum input noise match Z 0 = reference impedance Γ s = source match Page 0
EuMw Noise 007 parameters Aerospace Agilent Workshop Definition and Defense Symposium 007 Noise Temperature ( ) RT Y Y 4TR Γ Γ T = T + = T + n n 0 s opt 0 n opt s min min Gs Z0 1+Γopt 1 Γ T min minimum noise Temperature R n noise resistance T 0 90 K ( ) s Y opt optimum input admittance Y s = source admittance G s = real part of Y s Γ opt optimum input noise match Z 0 = reference impedance Γ s = source match Page 1
EuMw 007 Aerospace Agilent Workshop and Defense Symposium 007 Noise Parameters F min at Γ opt Plots of noise figure circles versus impedance (at one frequency) F min is lowest noise figure and occurs at Γ opt F changes with Γ F changes with device bias Increasing noise figure Increasing noise figure Page
EuMw Measuring 007 Aerospace Agilent Noise parameters Workshop and Defense Symposium 007 VNA TUNER Noise source DUT NFM A. C. Davidson, B. W. Leake, et al. (1989). "Accuracy improvements in microwave noise parameter measurements." Microwave Theory and Techniques, IEEE Transactions on 37(1): 1973-1978. Page 3
EuMw Noise 007 wave Aerospace Agilent representation Workshop and Defense S-parameters Symposium 007 b n a 1 b 1 a b [S] b n1 b1 s11 s1 a1 bn1 = + b s1 s a bn C s * b n1 bn 1bn cs11 cs1 = = * 1 bnbn1 b cs cs n P. Penfield, Jr "Wave Representation of Amplifier Noise." IRE Transactions On Circuit Theory: Mach (196) pp. 84-86 K. Hartmann, Noise Characterization of Linear Circuits, IEEE Transactions on Circuits and Systems, Vol. cas-3, No. 10, Oct. 1976, pp. 581-590 R.P. Meys, A Wave Approach to the Noise Properties of Linar Microwave Devices, IEEE Transactions on Microwave Theory and Techniques, Vol. MTT-6, No. 1, Jan. 1978, pp 34-37 S. W. Wedg,and D. B. Rutledge (199). "Wave techniques for noise modeling and measurement." Microwave Theory and Techniques, IEEE Transactions on 40(11): 004-01. Page 4
EuMw 007 Aerospace Agilent Workshop and Defense Symposium 007 Measurement using (S) noise correlation matrix Noise output power from two-port is P = kbg T + T P out av e out ( ) 0 ( 1 ) kbs Γ +Γ 1 + 1 s Ts s X = * 1 ΓsS11 1 Γ 11 + Re ( 1 Γ 11) Γ ss X 1 ss sx * bn cs bb n1 n cs1 1 = n1 = 11, = =, 1 = = * * S1 S S 1 1 S1 X b cs X X J. Randa, W. Wiatr, Conte Carlo Estimation of Noise Parameter Uncertainties, IEE Proc. Sci. Meas. Technology, Vol. 149, No. 6, Nov. 00, pp. 333-337 Page 5
EuMw 007 Aerospace Agilent Workshop and Defense Symposium 007 Noise correlation matrix (C S ) in terms of noise parameters C s ( ) ( )( ) 4 1 s 11 opt 4Rn opt 1 s R Γ Γ 11Γ n opt Fmin 1 s11 1 s 1 ( Fmin 1) s + 11 Z0 1 opt Z0 1 +Γ +Γopt = 4Rn opt ( 1 s11 opt ) 4R Γ Γ n Γopt s 1 ( Fmin 1) s 11 s 1 Fmin 1 Z0 1+Γ opt Z0 1+Γ opt Page 6
EuMw 007 Aerospace Agilent Workshop and Defense Symposium 007 New Noise Measurement System Noise Receiver Inside Noise Tuner DUT Noise Source ADAPTER Page 7
EuMw 007 Aerospace Agilent Workshop and Defense Symposium 007 ECal as Noise Tuner PNA-X varies source match around 50 ohms using an ECal module ECal can provide 7 impedance states (Z 1, F 1 ), (Z, F ), Page 8
EuMw 007 Aerospace Agilent Workshop and Defense Symposium 007 Noise Figure in PNA contributions Speed and accuracy Single Connection S-parameters and Noise Figure Fast Step Frequency Sweep Complete Mismatch Correction Use of ECal or Compatible Impedance Tuner Embedding and De-embedding of Probes in On- Wafer Noise Measurements Can Accommodate Coax Noise Source for On-Wafer Noise Measurements Page 9
EuMw 007 Aerospace Agilent Workshop and Defense Symposium 007 Calibration of the receiver P out ( 1 ) kbs Γ +Γ 1 + 1 s Ts s X = ( ) * 1 i ΓsS11 1 Γ 11 + Re 1 Γ ss X 11 Γ 1 ss sx 5 unknowns, linear equation Note: The PNA-X uses a different form of the above equation. Page 30
EuMw Calibration 007 Aerospace Agilent of receiver Workshop and Defense Symposium 007 - solution of equations Require Minimum Of 5 Equations To Solve Can Be Over-determined At Least One Measurement Must Be Made With Different Source Temperature Use Noise Source (Known ENR, Measure Γ Cold, Γ Hot ) ECal Module Provides 7 Terminations Page 31
EuMw 007 Aerospace Agilent Workshop and Defense Symposium 007 Noise Figure Mode Instrument Default Settings S-parameter Mode Source Power -30 dbm Noise RF BW 4 MHz Noise IF BW MHz Noise Averaging Point to Point (1 = 10K) Noise Receiver Gain 30 db Factory Receiver Cal ON Page 3
EuMw 007 Aerospace Agilent Workshop and Defense Symposium 007 Noise Figure Measurement Instrument Setup Page 33
EuMw Noise 007 Measurement Aerospace Agilent Workshop and Softkeys Defense Symposium 007 Page 34
EuMw Noise 007 Set Aerospace Agilent Up Workshop and Defense Symposium 007 Page 35
EuMw Noise 007 Set Aerospace Up Agilent Workshop and Defense Symposium 007 Page 36
EuMw Noise 007 Figure Aerospace Agilent Measurement Workshop and Defense Calibration Symposium 007 Page 37
EuMw Noise 007 Cal Aerospace Agilent Workshop and Defense Symposium 007 Page 38
EuMw 007 Aerospace Agilent Workshop and Defense Symposium 007 S-parameters and Noise Calibrations This step provides of the five measurements required. Noise Tuner Noise Source ADAPTER P h, P c, Γ h, Γ c Page 39
EuMw 007 Aerospace Agilent Workshop and Defense Symposium 007 S-parameters and Noise Calibrations This step provides the rest of measurements required to calibrate the noise receiver. Noise Tuner ADAPTER Γ nr P nt(i), Γ nt(i) Page 40
EuMw 007 Aerospace Agilent Workshop and Defense Symposium 007 S-parameters and Noise Calibrations S-parameter calibration completes the calibration sequence. Noise Tuner Page 41
EuMw 007 Aerospace Agilent Workshop and Defense Symposium 007 Measurement of DUT Known from Measured S-parameters P out ( 1 ) kbs Γ +Γ 1 + 1 s Ts s X = ( ) * 1 ΓsS11 1 Γ 11 + Re 1 Γ ss X 11 Γ 1 ss sx 4 unknowns, linear equation Page 4
EuMw 007 Aerospace Agilent Workshop and Defense Symposium 007 DUT S-parameters and Noise Measurement Noise Tuner Meas S-parameters DUT P out(i) @ each Γ nt(i) Page 43
EuMw 007 Aerospace Agilent Workshop and Defense Symposium 007 Noise Measurement System With On-Wafer Probes Noise Tuner FULL -port Cal 1-port Cal 4 Noise Source Page 44
EuMw 60 µm 007 FET Aerospace Agilent Workshop and Defense Symposium 007 Data sets offset by 1dB N8975 F (1 db per division) Y-factor cold corrected 0 5 10 15 0 5 Frequency (GHz) Page 45
EuMw 007 Aerospace Agilent Workshop and Defense Symposium 007 Measurements Compared 10 0 18 8 16 NF (db) 6 4 14 1 10 8 Gain (db) 0 NFA PNA/NF 1 3 4 5 6 Frequency (GHz) 6 4 0 Page 46
EuMw 007 Aerospace Agilent Workshop and Defense Symposium 007 Noise Figure Uncertainty Example (ATE Setup) 4.500 4.000 Amplifier: Gain = 15 db Input/output match = 10 db NF = 3 db Gamma opt = 0.68 0 o Fmin = 1.87 db Rn = 1 33 Y-factor with noise source connected to DUT via switch matrix NF (db) 3.500 3.000 0.75 db 0.5 db Y-factor with noise source directly at DUT input PNA-X 0. db.500.000 0.5.5 4.5 6.5 8.5 10.5 1.5 14.5 16.5 18.5 0.5.5 4.5 6.5 GHz Page 47
EuMw Noise 007 Figure Aerospace Agilent Uncertainty Workshop and Defense Example Symposium 007 (Wafer Setup) 4.500 4.000 1.1 db Amplifier: Gain = 15 db Input/output match = 10 db NF = 3 db Gamma opt = 0.68 0 o Fmin = 1.87 db Rn = 1 33 Y-factor with noise source connected Y-factor to DUT with via noise switch source matrix connected to probe via switch matrix 3.500 Y-factor with noise source connected to DUT input Y-factor with noise source 0.75 db connected to probe input PNA-X NF (db) PNA-X 0.3 db 3.000.500 Amplifier: Gain = 15 db Input/output match = 10 db NF = 3 db Gamma opt = 0.68 0 o Fmin = 1.87 db Rn = 1 33 Wave model correlation = 50%.000 0.5.5 4.5 6.5 8.5 10.5 1.5 14.5 16.5 18.5 0.5.5 4.5 6.5 GHz Page 48
EuMw 007 Aerospace Agilent Workshop and Defense Symposium 007 Verification approach Need To Avoid Using An Active Device Cannot Guarantee Behavior Over Time Dependence On Temperature Noise May Be Injected Through Bias Supply Use Mismatched Transmission Line, Passive Device Noise Parameters, Noise Figure Are Calculated From S- parameters Can Cascade With Any Amplifier And De-embed Page 49
EuMw Mismatch 007 Aerospace Transmission Agilent Workshop and Defense Line Characteristics Symposium 007 Page 50
EuMw Noise 007 wave Aerospace Agilent representations Workshop and Defense Symposium 007 50 Ω 5 Ω 50 Ω AMP [T L ], [C L ] [T A ], [C A ] a nl a na a 1L b 1L [T L ] a L b L a 1A b 1A [T A ] b A a A b nl b na C tl * a * nl anlbnl a ; C na anabna ta * * b nlanl bnl bnaana bna = = Page 51
EuMw Measured 007 Aerospace S-parameters Agilent Workshop and Defense of Amplifier Symposium 007 Page 5
EuMw Calculated 007 Aerospace Agilent vs. Measured Workshop and Defense Combined Symposium S 007 11 Page 53
EuMw Calculated 007 Aerospace Agilent vs. Measured Workshop and Defense Combined Symposium Gain 007 Page 54
EuMw 007 Aerospace Agilent Workshop and Defense Symposium 007 Calculated vs. Measured Combined Noise Figure Uncertainty Bar k= Page 55
EuMw 007 Aerospace Agilent Workshop and Defense Symposium 007 Additional References: [1] D. Vondran, Noise Figure Measurement: Corrections Related to Match and Gain, Microwave J., pp -38, Mar. 1999 [] Collantes, J. M., R. D. Pollard, et al. (00). "Effects of DUT mismatch on the noise figure characterization: a comparative analysis of two Y-factor techniques." Instrumentation and Measurement, IEEE Transactions on 51(6): 1150-1156. [3] Fundamentals of RF and Microwave Noise Figure Measurements, Hewlett-Packard Application Note 57-1, Palo Alto, CA July 1983 [4] IRE Subcommittee 7.9 On Noise: Representation Of Noise In Linear Two-ports, Proc. IRE, Vol. 48, Pp. 69-74, Jan. 1960 [4] A. C. Davidson, B. W. Leake, et al. (1989). "Accuracy improvements in microwave noise parameter measurements." Microwave Theory and Techniques, IEEE Transactions on 37(1): 1973-1978. [5] R.Q. Lane, The Determination of Device Noise Parameters, Proceedings of the IEEE, Aug. 1969, pp. 1461-146 [6] P. Penfield, Jr "Wave Representation of Amplifier Noise." IRE Transactions On Circuit Theory: Mach (196) pp. 84-86 [7] K. Hartmann, Noise Characterization of Linear Circuits, IEEE Transactions on Circuits and Systems, Vol. cas-3, No. 10, Oct. 1976, pp. 581-590 [8] R.P. Meys, A Wave Approach to the Noise Properties of Linar Microwave Devices, IEEE Transactions on Microwave Theory and Techniques, Vol. MTT-6, No. 1, Jan. 1978, pp 34-37 [9] S. W. Wedg,and D. B. Rutledge (199). "Wave techniques for noise modeling and measurement." Microwave Theory and Techniques, IEEE Transactions on 40(11): 004-01. [10] J. Randa, W. Wiatr, Conte Carlo Estimation of Noise Parameter Uncertainties, IEE Proc. Sci. Meas. Technology, Vol. 149, No. 6, Nov. 00, pp. 333-337 [11] E.C. Valk, D. Routledge, J.F. Vaneldik, T.L. Landecker, De-Embedding Two-Port Noise Parameters Using a Noise Wave Model, IEEE Transactions on Instrumentation and Measurement, vol. 37, no., June 1988, pp 195-00 Page 56
EuMw Noise 007 Option Aerospace Agilent Block Workshop and Diagram Defense Symposium 007 OUT 1 Source 1 OUT Source OUT 1 OUT 4V DC Noise receivers Rear panel R1 10 MHz - 3 GHz 3-6.5 GHz A R 35 db B 65 db 65 db 35 db Test port 1 Source Output 1 DU T Source Output Test port Noise Source Page 57