The measurements for Power Spectral
Density is performed at normal environmental conditions only. The test results comply
with the limits shown in the Power Spectral Density section in CE
Regulations for SRDs Operating in License-Free 2.4 GHz/5 GHz Bands
[1] and is recorded in the test report. The test procedure for Power
Spectral Density measurement is described in the following steps:
- Connect the EUT as shown in Figure 2-1.
- Use Spectrum Analyzer as test
equipment.
- For detailed test procedure, see
clause 5.4.3.2.1 of EN 300 328 [3].
- Switch ON the EUT and other test
equipment.
- Set the Spectrum Analyzer to the
following settings:
- Center Frequency: The center
frequency of the channel under test
- Reference Level: 30 dBm
- RBW: 1 MHz
- VBW: 3 MHz
- Frequency Span: >
2*OCBW
- Sweep Time: Auto
- Detector: Peak
- Trace Mode: Max Hold
- Use the Radio Testing Tool [9] to setup and configure the EUT. For setting and up configuring
the EUT, see the Radio Testing Tool User's Guide [10].
- Open the Radio Testing Tool [9] and setup the link with the EUT by using the Setup tab.
- Open the Tx tab and set the
transmission mode to “Continuous”.
- Configure the EUT to the desired
parameters such as Channel / Frequency, Data Rate, Data Pattern, Power Level, and so
forth).
- Click on “ Start Tx Testing”.
- Observe the Tx signal on the spectrum
analyzer. When the trace is complete, find the peak power by using peak marker
function. Record the frequency of the peak marker.
- Modify the settings of the Spectrum
Analyzer to the following settings:
- Center Frequency: Equal to
the center frequency of the marker (from the above step)
- Frequency Span: 3 MHz
- Reference Level: 30dBm
- RBW: 1 MHz
- VBW: 3 MHz
- Sweep Time: 1 Minute
- Detector: RMS
- Trace Mode: Max Hold
- Observe the Tx signal on the spectrum
analyzer. When the trace is complete, find the peak power by using peak marker
function. Record the highest power value (D in dBm / MHz).
- Add the antenna gain (G in dBi) and
an additional beamforming gain (Y in dB, if applicable).
- The resultant Power Spectral Density
(PSD) in e.i.r.p. equal to (D+G+Y) from the above steps. Record this value.
- Repeat the above for other data rates
/ modulations and also other desired channels.
- The Power Spectral Density (PSD) in
e.i.r.p. complies with the limits shown in the Power Spectral Density
section in CE Regulations for SRDs Operating in License-Free 2.4 GHz/5
GHz Bands [1] for all the above test cases.