182 Chapter 4
Downloading and Using Files
Downloading Directly into Pattern RAM (PRAM)
Downloading Directly into Pattern RAM (PRAM)
NOTE References to pattern RAM (PRAM) are for descriptive purposes only, relating to the
manner in which the memory is being used. PRAM and volatile waveform memory
(WFM1) actually utilize the same storage media.
Typically, the signal generator’s firmware generates the required data and framing structure and loads this
data into Pattern RAM (PRAM). The data is read by the baseband generator, which in turn is input to the I/Q
modulator. The signal generator can also accept data downloads directly into PRAM from a computer.
Programs such as MATLAB or MathCad can generate data which can be downloaded directly into PRAM in
either a list format or a block format.
Direct downloads to PRAM allow complete control over bursting, which is especially helpful for designing
experimental or proprietary framing schemes.
The signal generator’s baseband generator assembly builds modulation schemes by reading data stored in
PRAM and constructing framing protocols according to the data patterns present. PRAM data can be
manipulated (types of protocols changed, standard protocols modified or customized, etc.) using either the
front panel interface, or remote-commands.
Preliminary Setup
CAUTION Set up the digital communications format before downloading data. This enables the signal
generator to define the modulation format, filter, and data clock. Activating the digital
communications format after the data has been downloaded to PRAM can corrupt the
downloaded data.
To Next Page
Loading...
Need help?
General
