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Future of Vector Network Analysis Dylan Williams and Nate Orloff Integrated Circuits Drive Wireless Communications

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Future of Vector Network Analysis Dylan Williams and Nate Orloff Integrated Circuits Drive Wireless Communications Future of Vector Network Analysis Dylan Williams and Nate Orloff Integrated Circuits Drive Wireless Communications Application Frequency (GHz) 10 30 100 300 1000 100 10 Transit Frequency (GHz) Frequency Transit 1990 1995 2000 2005 2010 2015 2020 Year We Cannot Take the Integrated Circuit for Granted at mmWaves 2 Next 15 Years of Wireless Manufacturing by Country The United States still dominates mmWave manufacturing Enables $12.3T in Total Economic Growth (2020-2035) Communication Providers Want Speed of Fiber on Your Phone Millimeter-Waves are the Next Wireless Frontier Measurements and Calibrations Matter at mmWaves Before Calibration 64 QAM at 44 GHz After Calibration mmWave Measurement Challenge of our Era Not a Single RF Connector! On-Wafer IC and System-Level Test OTA System-Level Test Transistor models IC Test System-Level Test End-to-End Verification On-Wafer Connectorized Free-Space Goals for Vector Network Analysis in CTL Project Calibration Reference Planes On-Wafer and to OTA Test On-Wafer Measurements • Innovations in Calibration • Support Device Models to System-Level Test • State-Of-The-Art Instruments for US mmWave NR Manufacturers Vector Network Analysis • Platform for Traceable System-Level Tests Across CTL • Close the Connector-Less Gap mmWave Design Extremely Complex Accurate measurements are a must 80 80 GHz GHz 160 ~ GHz 240 GHz • Highly nonlinear operating states required for efficiency • Characterize, capture, control and reuse harmonics • Must maintain linearity On-Wafer Measurement the Only Way to Test ICs Yesterday Today CTL On-Wafer Accomplishments NIST On-Wafer Approaches Firmly Established as the Methods of Reference 20 With coupling correction ) No coupling correction B 18 d ( 30 n i a G M axim um stable gain 16 e l b a t S 95 % confidence intervals 14 m u m i x a 12 M 20 ) 10 B 50 100 150 200 d t ( Frequency (GHz) n a t 5.0 0 t n n s i a n t o s a c n o 4.5 c i G c r -0.2 t c c i r e t 10 l c e 4.0 i e l d IBM 45 nm SOI e Silicon 45 nm SOI i -0.4 e d v TDARPAHz BC THzB Electronics i t e 3.5 c v i e t f f c e e -0.6 f f f o e 3.0 t f r o a t p r -0.8 a 2.5 y r p a 0 l n a i e g R 0 100 200 300 400 500 600 700 2.0 -1.0 a m 0 100 200 300 400 500 600 700 I Frequency (G H z) Frequency (GHz) Microwave Design Strategy Evolved Greatly CTL Has Been Evolving Vector Network Analysis 50 Years Later OTA system-level behavior On-wafer On-wafer Impedances, reflections and waves voltages and currents system-level behavior Vector Network Analysis Today Same network analyzer • S-parameter calibration • Add Power and Electrical-Phase calibration 푏푖 푆푖푗 = S-Parameter 푎푗 푣 = 푍0 푎 + 푏 Power 1 푖 = 푎 − 푏 푍0 Phase The Future of On-Wafer Vector Network Analysis CTL Innovating in S-Parameters, Power and Electrical Phase Scattering-Parameter Calibration Kit Power Meter Electrical Phase Reference Today Tomorrow A Conduit for Traceability Inside and Outside CTL Vector Network Analysis Brings Power, Electrical Phase, Impedance and Waveforms to Remote Reference Planes Correlated Uncertainty NIST Waveform Services T Y = J X J PD Frequency Microwave Power Services 14 Time S-Parameter Services Vector Network Analyzer Impedance Microwave IC Design Modulated Signal Quality Free-Field Test OTA System-Level Measurements RF Customer Array RF RF IF RF OTA Measurements VNA Traceability For: • Channel Distortion, AoA and Polarization • Flexible RF-RF and RF-IF Measurements Characterize Fields • Multiple Traceable Modulated Signals Some Outcomes of CTL Vector Network Analysis On-Wafer Measurements VNA Measurement Methods • On-Wafer Device-Modeling Capability with Uncertainty • Improved VNA Synchronization for Accurate Modulated-Signal Measurement • GaN manufacturer asks for models with uncertainty • Using similar technique Keysight announces accurate EVM • On-Wafer Impedance-Power-Phase Calibration Kits measurements with VNA • Power Standard with 100 GHz BW • Traceable Characterization of any Signal AWG can Generate • Fabricated experimental on-wafer phase reference • Arbitrary frequency grid, dramatically improved sync/SNR • On-Wafer Instruments in a Probe • Investing in Calibration Services • Self-calibrating, connector-less, 1 THz BW • 4 New Staff Members • Waveform calibrations report both conventional and correlated uncertainties • Power and Scattering-Parameter Services migrating toward VNA transfers and correlated uncertainties Impact on Instrument Makers • Keysight adopts calibrated NIST Photodiodes for oscilloscope and electrical-phase traceability • Instrument Maker adds electrical phase reference and asks for NIST traceability • Instrument Maker announces 220 GHz VNA with no Coaxial Calibration Kit • Joint experiments to investigate direct NIST photodiode calibrations • Need 220 GHz calibration kits supporting on-wafer impedance-power-phase The Future of Vector Network Analyzers Probe Photomixer 1. Control 2. Convert 3.1 Amplify 3.2 Combine Diagnostic Signal Voltage (V) Voltage Time (ps) Everything in a Probe to Measure mmWave ICs Vector Network Analyzer in-a-Probe 60 GHz – 270 GHz VNA-in-a-probe Probe-Station 60 GHz – 270 GHz VNA-on-a-chip Mount mmWave Probe Tip IC 3 mm CTL at Cutting Edge of On-Wafer-to-OTA Test mmWaves are the Wireless Frontier Vector Network Analysis The Heart of CTL Services, IC Design and OTA System-Level Test On-Wafer System-Level Test Free-Space.
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