New Application Note: RF Budget Analysis Using Virtual System Simulator

Analyzing an RF system for gain, power, noise, and distortion goes by terms such as RF budget analysis, link budget analysis and cascade analysis. In this kind of analysis, the designer is tasked not only with computing these various RF performance criteria, but also applying the results in order to optimize the entire system for RF performance.

Cascade analysis finds application throughout the entire design process. At the beginning stages of the system design, cascade analysis helps with early topology choices as well as component selection. Throughout the design, refinements based on actual device performance require cascade analysis updates to ensure the overall system design is still on track. Final system verification tasks include using cascade analysis with statistical device parameter variations, temperature variation, extremes of input and output power levels and a list of other possible measurements that a unique to a particular design.

Cadence® AWR Design Environment® contains advanced tools tailored specifically for cascade analysis within its Virtual System Simulator®. RF Budget (RFB) is the primary tool for cascade analysis. RF Inspector (RFI) is another tool targeting the analysis of distortion products.

This application note documents the use of RF Budget for cascade analysis and RF Inspector for added distortion analysis capability. The large number of cascade measurements coupled with numerous options for each measurement can seem overwhelming at first. The intent is to dispel that overwhelming feeling by introducing some cascade measurement theory in addition to in depth discussion on how to effectively use the RFB and RFI measurements.