8 GHz Agile Synthesizer
The PicoSynth 2 software presents a clean, efficient, touchscreen-compatible user interface for direct and convenient access to synthesis parameters. These can be typed, scrolled or stepped by a configurable increment value, in a selectable unit of measure such as dBm, mW, V RMS, V pk-pk or degrees and radians. Its flexibility matches or exceeds that of the traditional control panel of a benchtop synthesizer.
The controls are presented in three independent parameter tabs, each of which holds separate settings for convenient mode switching:
Set carrier wave frequency, level and phase using typed values or scrolled digits, or by stepping by an increment of your choice, and then enable the output. When required add frequency (FM), phase (ØM or PM) or amplitude (AM) modulation using internal sine modulation synthesis or an external DC-coupled source connected to the front-panel BNC interface. Modulations are derived from digital IQ modulation and the external trigger output (rear-panel BNC) is synchronous with the internal modulation source.
Set up sweeps and hops between two parameter values: start of sweep and end of sweep (stop). Either can be the higher value. Set the number of points in a sweep (between 2 and 10 001 points). The dwell time then defines a duration for which each point in the sweep will be output. PicoSynth calculates and displays the duration of the whole sweep and the linear step size between each point. A bidirectional sweep will sweep from the start to stop and back to start in completing a single sweep of the parameter. A hop is a limited case of sweep in which there are only two parameter values that are alternately output.
The AS108 can sweep or hop the frequency, level or phase parameter. It can also sweep or hop two parameters at the same time: frequency and level, or phase and level. This allows, for instance, a simple linear flatness or loss-compensating profile to be applied to a sweep or hop, perhaps increasing output level as frequency increases. The example shown applies a 5 dBm increase in level as the frequency sweeps from 1 GHz to 2 GHz. Sweeps and hops can be synchronized to external events and instruments using the external trigger input and output (rear panel BNCs) or software trigger. Trigger occurs at, or initiates, a sweep start or next point in sweep. This synchronization flexibility can be of particular value to high-speed system sequencing in, for example, high-speed test.
Import a parameter list file to generate an arbitrary sequence of frequency/level or phase/level points. The file is in a straightforward comma-separated values (CSV) format that you can create using any text editor or export from a spreadsheet program.
PicoSynth 2 shows a summary of the file contents to help you verify that you have selected the correct file. You can program the dwell time (time between points) and trigger mode.
Parameter step increment values and the saving and recall of user settings are found under the Settings tab.
In a future firmware update, we plan to enable the loading of modified power-up settings into the device, allowing the signal source to power up in a known state without further connection or control over USB.