Rigol DG4062, Руководство пользователя

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RIGOL Chapter 5 Modulated Waveform Output
DG4000 User's Guide
5-22
To Select the Modulating Waveform Source
BPSK uses internal modulation source. Press Data Source to select PN15, PN21,
01 or 10and the default is PN15.
Explanation:
PN sequence (Pseudo-noise Sequence), a kind of periodic binary sequence,
has the statistical characteristics similar to a random noise but can be
produced and processed repeatedly. The most commonly used PN sequence
is m sequence generated by shift registers with linear feedback and its period
is relevant to the linear feedback logic and the initial state of each register.
The period of the m sequence generated by n-level shift register is 2
n
-1. As
In the figure below is a 4-level linear feedback shift register of which the
feedback logic is a3
⊕
a2. For PN15 and PN21, 15 and 21are levels of the
registers.
a3 a2 a1
a0
+
Output
To Set the BPSK Rate
BPSK uses internal modulation source. Press Rate to set the frequency at which
the output phase shifts between "carrier phase" and "modulating phase".

Use the numeric keyboard or direction keys and knob to input the desired
frequency value.

The frequency range is from 2mHz to 1MHz and the default is 100Hz.