R&S FSL spectrum analyzer

Connecting to the instrument via network

Once connected to the network, the instrument’s IP address can be found by clicking the “Setup” button and navigating to “General Settings” -> “Network Address”.

It can then be connected like this:

from pymeasure.instruments.rohdeschwarz import FSL
fsl = FSL("TCPIP::192.168.1.123::INSTR")

Getting and setting parameters

Most parameters are implemented as properties, which means they can be read and written (getting and setting) in a consistent and simple way. If numerical values are provided, base units are used (s, Hz, dB, …). Alternatively, the values can also be provided with a unit, e.g. "1.5 GHz" or "1.5GHz". Return values are always numerical.

# Getting the current center frequency
fsl.freq_center

9000000000.0

# Changing it to 10 MHz by providing the numerical value
fsl.freq_center = 10e6

# Verifying:
fsl.freq_center

10000000.0

# Changing it to 9 GHz by providing a string and verifying the result
fsl.freq_center = '9GHz'
fsl.freq_center

9000000000.0

# Setting the span to maximum
fsl.freq_span = '7 GHz'

Reading a trace

We will read the current trace

x, y = fsl.read_trace()

Markers

Markers are implemented as their own class. You can create them like this:

m1 = fsl.create_marker()

Set peak exursion:

m1.peak_excursion = 3

Set marker to a specific position:

m1.x = 10e9

Find the next peak to the left and get the level:

m1.to_next_peak('left')
m1.y

-34.9349060059

Delta markers

Delta markers can be created by setting the appropriate keyword.

d2 = fsl.create_marker(is_delta_marker=True)
d2.name

'DELT2'

Example program

Here is an example of a simple script for recording the peak of a signal.

m1 = fsl.create_marker() # create marker 1

# Set standard settings, set to full span
fsl.continuous_sweep = False
fsl.freq_span = '18 GHz'
fsl.res_bandwidth = "AUTO"
fsl.video_bandwidth = "AUTO"
fsl.sweep_time = "AUTO"

# Perform a sweep on full span, set the marker to the peak and some to that marker
fsl.single_sweep()
m1.to_peak()
m1.zoom('20 MHz')

# take data from the zoomed-in region
fsl.single_sweep()
x, y = fsl.read_trace()

class pymeasure.instruments.rohdeschwarz.fsl.FSL(adapter, name='Rohde&Schwarz FSL', **kwargs)

Bases: SCPIMixin, Instrument

Represents a Rohde&Schwarz FSL spectrum analyzer.

All physical values that can be set can either be as a string of a value and a unit (e.g. “1.2 GHz”) or as a float value in the base units (Hz, dBm, etc.).

property attenuation: Attenuation in dB.

continue_single_sweep(): Continue with single sweep with synchronization.

property continuous_sweep: Continuous (True) or single sweep (False)

create_marker(num=1, is_delta_marker=False)

Create a marker.

Parameters

num – The marker number (1-4)
is_delta_marker – True if the marker is a delta marker, default is False.

Returns

The marker object.

property freq_center: Center frequency in Hz.

property freq_span: Frequency span in Hz.

property freq_start: Start frequency in Hz.

property freq_stop: Stop frequency in Hz.

read_trace(n_trace=1)

Read trace data.

Parameters: n_trace – The trace number (1-6). Default is 1.
Returns: 2d numpy array of the trace data, [[frequency], [amplitude]].

property res_bandwidth: Resolution bandwidth in Hz. Can be set to ‘AUTO’

single_sweep(): Perform a single sweep with synchronization.

property sweep_time: Sweep time in s. Can be set to ‘AUTO’.

property trace_mode: Trace mode (‘WRIT’, ‘MAXH’, ‘MINH’, ‘AVER’ or ‘VIEW’)

property video_bandwidth: Video bandwidth in Hz. Can be set to ‘AUTO’