Instrumentation & Measurement Magazine 23-2 - 17

Fig. 5. Measurement setup of the intermediate frequency method.

meter in μV. Specifically: Venv is the amplitude of the IF pulse
envelope (see the example in Fig. 6) in V; Vosc,pp is the peak-topeak amplitude of the receiver response (IF output) to a CW
sine signal measured by the oscilloscope in V; IBW is the receiver impulse bandwidth in Hz; kpeak takes into account the
uncertainty of the peak ratio of the response to pulse/CW signal (dimensionless); kosc takes into account the oscilloscope
frequency response (dimensionless); and kIBW takes into account the uncertainty of the determination of the impulse
bandwidth (dimensionless).
The receiver impulse bandwidth is calculated as [13]:
	

IBW =

Venv
10 N
X ⋅  venv , k
N k =1

Hz,	(4)

where: Venv is the amplitude of the IF pulse envelope (see the
example in Fig. 6) in V; X is the oscilloscope horizontal resolution in s/div; N is the number of samples of the envelope [-];
and venv,k represents the k-th sample of the IF pulse envelope in
V. The 10 takes into account the number of oscilloscope horizontal screen divisions.
The determination of the IF pulse envelope can be done
using different methods which results in slightly different
calculated receiver impulse bandwidth and, consequently,
spectrum amplitude. Either the envelope can be calculated
as a moving average of the voltage IF trace (with e.g., 50 - 200
samples window), or it can be calculated as a magnitude of the
Hilbert transform of the IF voltage trace (time-domain). It is
convenient to filter the envelope trace using a low-pass filter to
remove the noise (which is obvious in Fig. 6b). The area under
the envelope is then calculated as a sum of the voltage samples
divided by the number of envelope samples. The spectrum
amplitude was calculated using (6) from oscilloscope samples
of the voltage at the IF output of an EMI receiver, and their values together with the measurement uncertainty are given in
Table 4.

Measurement of Pulse Amplitude and Duration
This method uses an oscilloscope, whereas the pulse is sampled with high time-resolution. The method is most suitable
for pulse-modulated RF generators. The spectrum amplitude
is calculated from the area of the pulse in V·s. The ideal measurement equation can be written as follows:
	

S ( f ) = U rms ⋅ T ⋅ kcor	(5)

where: Urms is the un-modulated CW signal level; T is the modulation pulse duration; and kcor is a correction factor taking into
account the signal level change after switching ON the pulse.

Fig. 6. Response of the receiver to a pulse signal. (a) + Envelope of the signal; (b) Unfiltered envelope.
April 2020	

IEEE Instrumentation & Measurement Magazine	17



Instrumentation & Measurement Magazine 23-2

Table of Contents for the Digital Edition of Instrumentation & Measurement Magazine 23-2

No label
Instrumentation & Measurement Magazine 23-2 - No label
Instrumentation & Measurement Magazine 23-2 - Cover2
Instrumentation & Measurement Magazine 23-2 - 1
Instrumentation & Measurement Magazine 23-2 - 2
Instrumentation & Measurement Magazine 23-2 - 3
Instrumentation & Measurement Magazine 23-2 - 4
Instrumentation & Measurement Magazine 23-2 - 5
Instrumentation & Measurement Magazine 23-2 - 6
Instrumentation & Measurement Magazine 23-2 - 7
Instrumentation & Measurement Magazine 23-2 - 8
Instrumentation & Measurement Magazine 23-2 - 9
Instrumentation & Measurement Magazine 23-2 - 10
Instrumentation & Measurement Magazine 23-2 - 11
Instrumentation & Measurement Magazine 23-2 - 12
Instrumentation & Measurement Magazine 23-2 - 13
Instrumentation & Measurement Magazine 23-2 - 14
Instrumentation & Measurement Magazine 23-2 - 15
Instrumentation & Measurement Magazine 23-2 - 16
Instrumentation & Measurement Magazine 23-2 - 17
Instrumentation & Measurement Magazine 23-2 - 18
Instrumentation & Measurement Magazine 23-2 - 19
Instrumentation & Measurement Magazine 23-2 - 20
Instrumentation & Measurement Magazine 23-2 - 21
Instrumentation & Measurement Magazine 23-2 - 22
Instrumentation & Measurement Magazine 23-2 - 23
Instrumentation & Measurement Magazine 23-2 - 24
Instrumentation & Measurement Magazine 23-2 - 25
Instrumentation & Measurement Magazine 23-2 - 26
Instrumentation & Measurement Magazine 23-2 - 27
Instrumentation & Measurement Magazine 23-2 - 28
Instrumentation & Measurement Magazine 23-2 - 29
Instrumentation & Measurement Magazine 23-2 - 30
Instrumentation & Measurement Magazine 23-2 - 31
Instrumentation & Measurement Magazine 23-2 - 32
Instrumentation & Measurement Magazine 23-2 - 33
Instrumentation & Measurement Magazine 23-2 - 34
Instrumentation & Measurement Magazine 23-2 - 35
Instrumentation & Measurement Magazine 23-2 - 36
Instrumentation & Measurement Magazine 23-2 - 37
Instrumentation & Measurement Magazine 23-2 - 38
Instrumentation & Measurement Magazine 23-2 - 39
Instrumentation & Measurement Magazine 23-2 - 40
Instrumentation & Measurement Magazine 23-2 - 41
Instrumentation & Measurement Magazine 23-2 - 42
Instrumentation & Measurement Magazine 23-2 - 43
Instrumentation & Measurement Magazine 23-2 - 44
Instrumentation & Measurement Magazine 23-2 - 45
Instrumentation & Measurement Magazine 23-2 - 46
Instrumentation & Measurement Magazine 23-2 - 47
Instrumentation & Measurement Magazine 23-2 - 48
Instrumentation & Measurement Magazine 23-2 - 49
Instrumentation & Measurement Magazine 23-2 - 50
Instrumentation & Measurement Magazine 23-2 - 51
Instrumentation & Measurement Magazine 23-2 - 52
Instrumentation & Measurement Magazine 23-2 - 53
Instrumentation & Measurement Magazine 23-2 - 54
Instrumentation & Measurement Magazine 23-2 - 55
Instrumentation & Measurement Magazine 23-2 - 56
Instrumentation & Measurement Magazine 23-2 - 57
Instrumentation & Measurement Magazine 23-2 - 58
Instrumentation & Measurement Magazine 23-2 - 59
Instrumentation & Measurement Magazine 23-2 - 60
Instrumentation & Measurement Magazine 23-2 - 61
Instrumentation & Measurement Magazine 23-2 - 62
Instrumentation & Measurement Magazine 23-2 - 63
Instrumentation & Measurement Magazine 23-2 - 64
Instrumentation & Measurement Magazine 23-2 - 65
Instrumentation & Measurement Magazine 23-2 - 66
Instrumentation & Measurement Magazine 23-2 - 67
Instrumentation & Measurement Magazine 23-2 - 68
Instrumentation & Measurement Magazine 23-2 - 69
Instrumentation & Measurement Magazine 23-2 - 70
Instrumentation & Measurement Magazine 23-2 - 71
Instrumentation & Measurement Magazine 23-2 - 72
Instrumentation & Measurement Magazine 23-2 - 73
Instrumentation & Measurement Magazine 23-2 - 74
Instrumentation & Measurement Magazine 23-2 - 75
Instrumentation & Measurement Magazine 23-2 - 76
Instrumentation & Measurement Magazine 23-2 - 77
Instrumentation & Measurement Magazine 23-2 - 78
Instrumentation & Measurement Magazine 23-2 - 79
Instrumentation & Measurement Magazine 23-2 - 80
Instrumentation & Measurement Magazine 23-2 - 81
Instrumentation & Measurement Magazine 23-2 - 82
Instrumentation & Measurement Magazine 23-2 - 83
Instrumentation & Measurement Magazine 23-2 - 84
Instrumentation & Measurement Magazine 23-2 - 85
Instrumentation & Measurement Magazine 23-2 - 86
Instrumentation & Measurement Magazine 23-2 - 87
Instrumentation & Measurement Magazine 23-2 - 88
Instrumentation & Measurement Magazine 23-2 - 89
Instrumentation & Measurement Magazine 23-2 - 90
Instrumentation & Measurement Magazine 23-2 - 91
Instrumentation & Measurement Magazine 23-2 - 92
Instrumentation & Measurement Magazine 23-2 - 93
Instrumentation & Measurement Magazine 23-2 - 94
Instrumentation & Measurement Magazine 23-2 - 95
Instrumentation & Measurement Magazine 23-2 - 96
Instrumentation & Measurement Magazine 23-2 - 97
Instrumentation & Measurement Magazine 23-2 - 98
Instrumentation & Measurement Magazine 23-2 - 99
Instrumentation & Measurement Magazine 23-2 - 100
Instrumentation & Measurement Magazine 23-2 - 101
Instrumentation & Measurement Magazine 23-2 - 102
Instrumentation & Measurement Magazine 23-2 - 103
Instrumentation & Measurement Magazine 23-2 - 104
Instrumentation & Measurement Magazine 23-2 - 105
Instrumentation & Measurement Magazine 23-2 - 106
Instrumentation & Measurement Magazine 23-2 - 107
Instrumentation & Measurement Magazine 23-2 - 108
Instrumentation & Measurement Magazine 23-2 - 109
Instrumentation & Measurement Magazine 23-2 - 110
Instrumentation & Measurement Magazine 23-2 - 111
Instrumentation & Measurement Magazine 23-2 - 112
Instrumentation & Measurement Magazine 23-2 - 113
Instrumentation & Measurement Magazine 23-2 - 114
Instrumentation & Measurement Magazine 23-2 - 115
Instrumentation & Measurement Magazine 23-2 - 116
Instrumentation & Measurement Magazine 23-2 - 117
Instrumentation & Measurement Magazine 23-2 - 118
Instrumentation & Measurement Magazine 23-2 - 119
Instrumentation & Measurement Magazine 23-2 - 120
Instrumentation & Measurement Magazine 23-2 - Cover3
Instrumentation & Measurement Magazine 23-2 - Cover4
https://www.nxtbook.com/allen/iamm/24-6
https://www.nxtbook.com/allen/iamm/24-5
https://www.nxtbook.com/allen/iamm/24-4
https://www.nxtbook.com/allen/iamm/24-3
https://www.nxtbook.com/allen/iamm/24-2
https://www.nxtbook.com/allen/iamm/24-1
https://www.nxtbook.com/allen/iamm/23-9
https://www.nxtbook.com/allen/iamm/23-8
https://www.nxtbook.com/allen/iamm/23-6
https://www.nxtbook.com/allen/iamm/23-5
https://www.nxtbook.com/allen/iamm/23-2
https://www.nxtbook.com/allen/iamm/23-3
https://www.nxtbook.com/allen/iamm/23-4
https://www.nxtbookmedia.com