A measurement system for analyzing an RF signal, comprising - a sensing medium, including at least one constituent - being pumpable to an initial energy state, and - being excitable from the initial energy state to a higher energy state by exposure to an electric and/or magnetic field; - an optical pump configured to pump the at least one constituent of the sensing medium to the initial energy state; - an antenna configured to expose the sensing medium to an electromagnetic field of the RF signal in order to excite it; wherein light emanating from the pumped sensing medium has a spatial distribution, which depends on the frequency of the RF signal; the measurement system further comprising: - an optical processor comprising a trained diffractive deep neural network being an artificial neural network, ANN, that comprises a number of diffractive layers being arranged in series for traversal by the light emanating from the pumped medium, and that is configured to manipulate the spatial distribution of the light such as to apply a linear transformation to the light emanating from the pumped sensing medium, wherein the ANN is trained based on discrepancies between pairs of output light patterns and desired light patterns; and - an optical detector configured to detect an optical property of the transformed light. - a sensing medium, including at least one constituent - being pumpable to an initial energy state, and - being excitable from the initial energy state to a higher energy state by exposure to an electric and/or magnetic field; - being pumpable to an initial energy state, and - being excitable from the initial energy state to a higher energy state by exposure to an electric and/or magnetic field; - an optical pump configured to pump the at least one constituent of the sensing medium to the initial energy state; - an antenna configured to expose the sensing medium to an electromagnetic field of the RF signal in order to excite it; wherein light emanating from the pumped sensing medium has a spatial distribution, which depends on the frequency of the RF signal; the measurement system further comprising: - an optical processor comprising a trained diffractive deep neural network being an artificial neural network, ANN, that comprises a number of diffractive layers being arranged in series for traversal by the light emanating from the pumped medium, and that is configured to manipulate the spatial distribution of the light such as to apply a linear transformation to the light emanating from the pumped sensing medium, wherein the ANN is trained based on discrepancies between pairs of output light patterns and desired light patterns; and - an optical detector configured to detect an optical property of the transformed light. - an optical processor comprising a trained diffractive deep neural network being an artificial neural network, ANN, that comprises a number of diffractive layers being arranged in series for traversal by the light emanating from the pumped medium, and that is configured to manipulate the spatial distribution of the light such as to apply a linear transformation to the light emanating from the pumped sensing medium, wherein the ANN is trained based on discrepancies between pairs of output light patterns and desired light patterns; and - an optical detector configured to detect an optical property of the transformed light.