TIME-DOMAIN MEASUREMENT SYSTEM FOR IMPULSE NOISE CHARACTERIZATION Salvador Verdaguer Ferran Silva Electromagnetic Compatibility Group (GCEM). Technical University of Catalonia (UPC) Campus Nord, Edifici C4. c/ Jordi Girona Barcelona SPAIN

1.-Transient phenomena: measurement challenge 2.-First option: spectrum analyzers and EMI receivers 4.-Second option: wideband digital oscilloscopes 5.-Proposed solution: a hybrid architecture 6.-Signal path in frequency domain 9.-Real-transient measurements 10.-Conclusions Index

Transient phenomena Transient measurement and characterization is necessary to determine the effect of impulsive interferences on new electronic systems

High frequency Short duration Low level Transient characteristics Which is the most suitable equipment to measure them ?

● Broad frequency range ● High sensitivity ● Wide dynamic range Spectrum Analyzers and EMI Receivers Frequency sweep operation: Too slow Does not provide time information Trigger system usually asynchronous Zero-span operation: # Samples limited to # points on screen e.g.: RBW = 1 MHz  f S = 2 MHz 250 μs on a 500-point screen Real spectrum Measured spectrum

● Frequency range > 3 GHz ● Sample memory > 32 MB ● Versatile trigger ● Measurement accurate in amplitude and phase Wideband Digital Oscilloscopes Large bandwidth used in measurement process  higher noise level 8-bit ADC  narrow dynamic range A/D f High sampling frequencies  €€€ e.g.: f S = 5 GHz needed for 2,4 GHz ISM band

Spectrum analyzer or EMI receiver Proposed solution Acquisition System (digitizer board) Frequency-domain stage  High frequency  High sensitivity Time-domain stage  Large dynamic range > 10 bit  Deep sample memory > 32 MB

Proposed solution: general architecture 9 kHz – 3 GHz RBW  1 MHz ADC 14 bit 32 MB 64 MS/s Trigger stage IF OUTPUT R&S ESPI3 in Zero span mode NI PXI 5620

Signal path in frequency domain f f f f CF RBW = 1 MHz Zero span output IF output Digitizer system output 250 μs on-screen IF = 20,4 MHz >1 second captured

Real-transient measurement 2 m CF = 50 MHz RBW = 1 MHz Relay spark

Real-transient measurement 1 MHz BW centered at 100 MHz FM radio broadcast waveforms 82 dBuV/m 86 dBuV/m 4.4 kV ESD Transient in time domain

Real-transient measurement Clean RF band, no waveforms present 88 dBuV/m 4.4 kV ESD 1 MHz BW centered at 130 MHz Transient in time domain

Real-transient measurement 4.4 kV ESD Quiet GSM channel 34 dBuV/m 54 dBuV/m 1 MHz BW centered at 1803 MHz Transient in time domain

Real-transient measurement GSM Incoming call Signal seek in frequency domain: 100 MHz Span, MAX Hold 1803 MHz GSM channel

Real-transient measurement GSM Incoming call Time-domain 100 ms capture Time-domain 1,2 ms capture 48 dBuV/m 52 dBuV/m 1803 MHz GSM channel

Electronics production plant measurement Component insertion machines Rolling line: 30 m x 5 m

Electronics production plant measurement 3 frequency bands were considered: 150 MHz 433 MHz 2,4 GHz

Electronics production plant measurement 150 MHz band Frequency measurement 1 minute MAX hold step 1

Electronics production plant measurement 150 MHz band Time measurement 26 transients/minute 78 dBuV/m step 2

Electronics production plant measurement 433 MHz band Frequency measurement 1 min MAX hold step 1

Electronics production plant measurement 433 MHz band Time measurement 29 transients/minute 82 dBuV/m step 2

Electronics production plant measurement 2,4 GHz band Frequency measurement 1 min MAX hold step 1

Electronics production plant measurement 2,4 GHz band Time measurement 30 dBuV/m step 2

Measurement system based on external digitizing of spectrum analyzer or EMI receiver IF output Conclusions Allows time-domain measurement of signals Provide new uses to instruments already available in a typical EMC lab Can be used as a tool to study transient noise environments High frequency Non-periodic Low level