Applications of an envelope simulator

There are many applications of the Circuit Envelope simulator. Primarily it is used for efficiently simulating non-steady-state, digitally-modulated RF signals and transient RF signals that are found in many communications circuits and systems. Amplifier adjacent-channel power ratio, error vector magnitude, power added efficiency, frequency or phase versus time, etc. can be simulated. Transient responses of phase locked loops and automatic gain control loops can also be simulated. IQ modulators can be simulated efficiently with baseband modulation signals or sine wave inputs. The performance of receivers with modulated input signals can be simulated as well. Designers are no longer forced to characterize their circuits with unmodulated sine waves. Now, performance can be simulated with the digitally-modulated signals that the circuits will see in operation. Here is a list of typical applications: amplifier adjacent-channel power ratio (ACPR), error vector magnitude (EVM) and power-added efficiency (PAE) with modulated signals; phase locked loop (PLL) simulations: frequency-versus-time transient responses, reference oscillator feedthrough and time-domain noise simulation; I-Q modulator simulations: ACPR, EVM, baseband-to-RF signal mapping, intermodulation distortion; receiver simulation with modulated signals and interfering tones; AGC (automatic gain control) simulation.