Rohde & Schwarz ESRP Series, Руководство пользователя

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Receiver Mode
R&S
®
ESRP
122 User Manual 1175.7445.02 ─ 08
The scan can be performed as a single scan or continuously. In the case of single scan
it is stopped when the stop frequency is reached. The continuous scan can be interrup-
ted or terminated any time.
The maximal number of measured frequencies is limited to 4.000.000 per detector. The
data can be stored for postprocessing. If the scan subranges are defined so that more
than the possible values would be measured, a respective message is output upon the
scan start. Afterwards the scan is performed up to the maximum value.
Figure 5-1: Scan on selected frequencies showing gaps in the trace
The R&S ESRP offers three types of scans:
●
Stepped scan in the frequency domain
In stepped scan mode, step width and frequency spacing (step mode) can be
selected.
●
Time domain scan in the frequency domain
In time domain measurement systems, up to 30 MHz of the spectrum at the
receiver input are measured in parallel by using fast fourier transform (FFT) of fre-
quency sections. Time Domain scans require option R&S
ESRP-K53.
● Stepped Scans in the Frequency Domain .............................................................122
● Time Domain Scans in the Frequency Domain .....................................................123
● The Scan Table ..................................................................................................... 123
5.1.3.1 Stepped Scans in the Frequency Domain
In stepped scan mode, the step width and the frequency spacing (step mode) can be
selected. Linear, logarithmic or automatic frequency spacing is available. In automatic
mode, the step width is selected so that it is always smaller than the bandwidth.
EMI measurements may involve much time. Time saving procedures are explained in
Chapter 5.1.4, "Peak List and Data Reduction" , on page 124. They reduced the total
measurement time by reducing the number of quasipeak measurements to a minimum.
Nevertheless, this time is still very long, often in the order of hours, especially for the
CISPR radiated emissions tests. A way out of this situation can be time-domain mea-
surements, see
Chapter 5.1.3.2, "Time Domain Scans in the Frequency Domain" ,
on page 123.
Measurements and Result Displays