Tabor Electronics 5251, Руководство пользователя

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4
Remote Programming Reference
Modulated Waveforms Control Commands
4-63
PSK Modulation
Programming
Use the following command for programming the PSK parameters.
The PSK function can shift from start to shifted phase setting, within
the range of 0 to 360
°
, at a frequency determined by the rate value
and controlled by a sequence of bits in the PSK data table. Note
that the carrier waveform frequency (CW) setting is common to all
modulation schemes.
PSK:PHASe:<start_phase>(?)
Description
This programs the start phase of the carrier waveform. The start phase shifts when the pointer in the data
array points to “0”.
Parameters
Name Range Type Default Description
<start_phase> 0 to 360 Numeric 0 Programs the start phase for the carrier waveform in
units of degrees.
Response
The 5251 will return the present start phase value.
PSK:PHASe:SHIFted<shift_phase>(?)
Description
This programs the shifted phase. The phase shifts when the pointer in the data array points to “1”.
Parameters
Name Range Type Default Description
<shift_phase> 0 to 360 Numeric 180 Programs the shift phase for the carrier waveform in
units of degrees.
Response
The 5251 will return the present shift phase value.
PSK:DATA<psk_data>
Description
Loads the data stream that will cause the 5251 to hop from phase to phase. Data format is a string of "0"
and "1" which define when the output generates the various phases. The size of the data word depends on
the PSK function. For PSK and BPSK there are only two bits - "0" defines start phase,"1" defines shifted
phase. 16PSK has 4 bits of which 0000 defines the first phase vector 0001 defines the second, 0000 the
third and 1111 defines the 16th phase vector. Note that if you intend to program marker position, you must
do it before you load the PSK data list.