Efficient Circuit-Level Nonlinear Analysis of Interference in UWB Receivers

The paper demonstrates for the first time a circuit-level approach to the analysis of pulse-UWB receiver front ends in the presence of interfering communication signals. The procedure is based on a model-order reduction harmonic balance technique (MORHB) that has been especially devised to efficiently handle signal spectra including very large numbers of arbitrarily spaced lines. At each step of the nonlinear solution loop the GMRES iteration is used to find an approximate Newton update belonging to a suitable Krylov subspace, and a novel efficient algorithm for performing matrix-vector multiplications is exploited. The resulting simulation tool allows rigorous computation of interference effects on the nonlinear regime of UWB receivers and accurate circuit-level prediction of receiver sensitivity and channel capacitance. Simplifying assumptions typical of system-level approaches are overcome in this way, while keeping computational time at acceptable levels.