Keysight U8903B, Руководство пользователя

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4 Audio Analyzer Measurement Functions
184 Keysight U8903B User’s Guide
Measurement Functions
Frequency measurement
Frequency is a common and basic measurement function which is expressed in hertz (Hz).
The U8903B uses software algorithm to detect the period of a repetitive waveform, and the
frequency is computed from the reciprocal of the period.
To obtain better accuracy and resolution, auto ranging should be enabled. For
low-frequency signals, set a larger sample size to obtain better and more stable readings.
Input filters can also be activated to remove unwanted high-frequency noise from the
measured signal, allowing more stable readings.
Frequency measurement function mode is applicable for the analog, digital, and Bluetooth
analyzer. The settings for frequency measurement are displayed as shown in Figure 4-9 ,
Figure 4-10 , and Figure 4-11 for the analog, digital, and Bluetooth analyzer respectively.
Figure 4-9 Analog Analyzer > Functions > Frequency menu page 1
NOTE
A limitation in the firmware supplied by the Bluetooth chipset vendor causes the Bluetooth
analyzer frequency measurement for the A2DP profile under SBC codec at 44.1 kHz
sampling rate to exhibit a ±0.05% measurement error. Do expect approximately 30 s of
settling time for the first frequency measurement in the A2DP profile after the Open Media
Connection have been initiated.