RF System QuickStart Guide
This QuickStart Guide is intended to help you get started using the RF System Design Guide effectively. For detailed reference information, refer to RF System DesignGuide Reference.
The RF System DesignGuide has many simulation set-ups and data displays that are very useful for designing a communication system. The simulation setups are categorized by the System configuration, simulation technique, and type of topology. This DesignGuide is not a complete solution for all types of measurements and topologies, but covers the most common approaches. Subsequent releases of this DesignGuide will include an expanded range of features.
This documentation is written describing and showing access through the cascading menu preference. If you are running the program through the selection dialog box method, the appearance and interface will be slightly different.
All DesignGuides can be accessed in the Schematic window through either cascading menus or dialog boxes. You can configure your preferred method in the Advanced Design System Main window. Select the DesignGuide menu.
The commands in this menu are as follows:
DesignGuide Studio Documentation > Developer Studio Documentation is only available on this menu if you have installed the DesignGuide Developer Studio. It brings up the DesignGuide Developer Studio documentation. Another way to access the Developer Studio documentation is by selecting Help > Topics and Index > DesignGuides > DesignGuide Developer Studio (from any ADS program window).
DesignGuide Developer Studio > Start DesignGuide Studio is only available on this menu if you have installed the DesignGuide Developer Studio. It launches the initial Developer Studio dialog box.
Add DesignGuide brings up a directory browser in which you can add a DesignGuide to your installation. This is primarily intended for use with DesignGuides that are custom-built through the Developer Studio.
List/Remove DesignGuide brings up a list of your installed DesignGuides. Select any that you would like to uninstall and choose the Remove button.
Preferences brings up a dialog box that allows you to:
- Disable the DesignGuide menu commands (all except Preferences) in the Main window by unchecking this box. In the Schematic and Layout windows, the complete DesignGuide menu and all of its commands will be removed if this box is unchecked.
- Select your preferred interface method (cascading menus vs. dialog boxes).
Close and restart the program for your preference changes to take effect.
On PC systems, Windows resource issues might limit the use of cascading menus. When multiple windows are open, your system could become destabilized. Thus the dialog box menu style might be best for these situations.
Accessing the Documentation
To access the documentation for the DesignGuide, select either of the following:
- DesignGuide > RF System > RF System DesignGuide Documentation (from ADS Schematic window)
- Help > Topics and Index > DesignGuides > RF System (from any ADS program window)
The features and content of the RF System DesignGuide are accessible from the DesignGuide menu found in the ADS Schematic window.
Using a dialog box labeled Transmitter/Receiver Design on the menu, you select your desired communication configuration, as shown here.The first step is to select one of the two available system configurations from the RF System tab of the dialogue box.
Having identified the type of communication system, you then select one of the nine simulations available from the Simulation tab, as shown in the illustration that follows. The simulations include
- Source Modulation (you choose the type of modulation on the next tab)
- Noise Figure (Tabular Format)
- Carrier to Noise Ratio (Tabular Format)
- Carrier to Intermodulation Distortion (Tabular Format)
- Spurious Response (Table and Graph)
- Spurious Response as a function of the LO frequency (Table and Graph)
- S Parameters (Graphical Format)
- Gain Compression (Graphical Format)
- Carrier to Intermodulation Distortion with swept RF input power (Graphical Format)
Having selected Source Modulation on the previous tab, you then have a choice of modulations. If you have developed your own source modulation, you can replace the source on the schematic. The Not Applicable box will be highlighted if you have not chosen source modulation on the previous tab.
The selection box for source modulations is shown here.
Shown here is the selection box for system topology. The grayed-out selections are not available with the previous tab selections. Click one of the available selections. For a detailed description of the topology selections, refer to RF System DesignGuide. If the communication system is a transmitter, you have a choice of 6 topologies. If the communication system is a receiver, then you have a choice of 2 topologies. The topologies are functions of whether the upper sideband or lower sideband is used for each mixer.
The first step in most system designs is to select a topology. Typically a receiver uses either one or two stages of frequency conversion. Most receiver systems use the lower sideband of the mixer output at each frequency translation and therefore there are only two topologies. Whereas, for transmitters, the configurations are more varied, this DesignGuide has topologies for each of the four double stage up converters, as well as the two possible single stage up converters. There is a Transmitter example included to demonstrate how the pre-defined topology can be modified to your configuration
From the Schematic window, select DesignGuide > RF System Design Guide > Transmitter/Receiver Topologies.
To use the system topology within a Ptolemy simulation, there are co-simulation topology modules to facilitate the process. The topology that has been designed and tested with the Type of Measurement schematics can then be entered into these modules for further testing in the Ptolemy environment.
From the Schematic window, select DesignGuide > RF System Design Guide > Co-Simulation Topologies .
Some example files show how the co-simulation modules are inserted into the Ptolemy schematics. From the Schematic window, select DesignGuide > RF System DesignGuide > Communication Examples.
Display Simulation Results
The Display Simulation results menu selection is only present as a means of opening secondary data displays that correspond to a particular schematic. Most of the simulations with modulated signals have a second data display that shows the spectrum, power, and ACPR calculations. This secondary data display can only be opened via this menu selection. However, if you rename the schematic, the menu selection will not work anymore. For this reason, we recommend that you open the corresponding data display before renaming a schematic. After renaming schematics, you must open data displays using one of the standard ADS methods.