This project describes the creation of a power meter developed by MATLAB program. Once finished, the system must be able to provide information on the RMS (both Volts and dBm) of a given signal, the user must also show the signal in question and its power spectrum, which can be smoothed by a filter selectable low pass. In essence it will be its purpose though, to complement the task is added to the "power meter" an envelope detector. Thus, we can extract information from modulated signal amplitude, then any possible interference filter and measure the resulting energy to allow subsequent tasks.