Abstract: A circuit for signal classification in a digital pre-distortion (DPD) system is provided. The circuit includes a first frequency path with a positive frequency translation to generate a first power level corresponding to a signal output of the first frequency path, a second frequency path with a negative frequency translation to generate a second power level corresponding to a signal output of the second frequency path, and a third frequency path configured to filter the input signal via a high pass filter (HPF) and to generate a third power level corresponding to a signal output of the third frequency path. The circuit further includes a processing unit configured to compute frequency content metrics corresponding to the input signal based on the first power level, the second power level and the third power level for selecting a set of DPD coefficients for the DPD circuit.

Abstract: Method, systems, and devices for designing a test molecule are disclosed. An example method includes using a molecular simulator to generate sets of simulation data. Each set of simulation data may include simulation data indicative of simulated locations in a solvent of (i) molecules of a reference molecule and (ii) molecules of one of M test molecules. The method may also include determining a probability of contact between an a species and a ? species for each set of simulated data. A contact may occur when a particle of the ? species is within a range of radials distances from a particle of the ? species. Each of the a species and the ? species may be one of the reference molecule, the solvent, or one of the M test molecules. The method may further include determining a simulation result based on at least one probability of contact.