A band-pass filter is described comprising a first first-order filter stage comprising a first resistor characterized by a first impedance and connected to a first node, referred to as a filter input node, and, through a second node to a first reactive component connected to a third node, the first impedance being such that a first current therethrough is dependent on the difference between the voltages at the first and second nodes; and a second first-order filter stage comprising a second resistor characterized by a second impedance and connected to the second node, and, through a fourth node, to a second reactive component connected to a fifth node. The second impedance is such that a second current therethrough is dependent on the negative of the sum of the voltages at the second and fourth nodes. The band-pass filter further comprises summing means for summing the voltages at the second and fourth nodes to output a voltage at a sixth node.

Method and apparatus for nonlinear signal processing include mitigation of outlier noise in the process of analog-to-digital conversion and adaptive real-time signal conditioning, processing, analysis, quantification, comparison, and control. Methods, processes and apparatus for real-time measuring and analysis of variables include statistical analysis and generic measurement systems and processes which are not specially adapted for any specific variables, or to one particular environment. Methods and corresponding apparatus for mitigation of electromagnetic interference, for improving properties of electronic devices, and for improving and/or enabling coexistence of a plurality of electronic devices include post-processing analysis of measured variables and post-processing statistical analysis.

In a nonlinear signal filtering system, a signal having a series of signal samples is filtered. The signal samples are affected by interactions with adjacent signal samples and nonlinear distortions. The system contains a series of alternating linear system elements and nonlinear system elements that are used for mitigation of distortion resulting from the nonlinear distortions with memory effects. The linear system elements can scale each signal sample in the series of signal samples by scaling parameters and sums a plurality of consecutive scaled signal samples, and the nonlinear system elements can transform the output of the linear system elements according to instantaneous nonlinear functions.

In a nonlinear signal filtering system, a signal having a series of signal samples is filtered. The signal samples are affected by interactions with adjacent signal samples and nonlinear distortions. The system contains a series of alternating linear system elements and nonlinear system elements that are used for mitigation of distortion resulting from the nonlinear distortions with memory effects. The linear system elements can scale each signal sample in the series of signal samples by scaling parameters and sums a plurality of consecutive scaled signal samples, and the nonlinear system elements can transform the output of the linear system elements according to instantaneous nonlinear functions.

A band-pass filter is described comprising a first first-order filter stage comprising a first resistor characterised by a first impedance and connected to a first node, referred to as a filter input node, and, through a second node to a first reactive component connected to a third node, the first impedance being such that a first current therethrough is dependent on the difference between the voltages at the first and second nodes; and a second first-order filter stage comprising a second resistor characterised by a second impedance and connected to the second node, and, through a fourth node, to a second reactive component connected to a fifth node. The second impedance is such that a second current therethrough is dependent on the negative of the sum of the voltages at the second and fourth nodes. The band-pass filter further comprises summing means for summing the voltages at the second and fourth nodes to output a voltage at a sixth node.

In a nonlinear signal filtering system, a signal having a series of signal samples is filtered. The signal samples are affected by interactions with adjacent signal samples and nonlinear distortions. The system contains a series of alternating linear system elements and nonlinear system elements that are used for mitigation of distortion resulting from the nonlinear distortions with memory effects. The linear system elements can scale each signal sample in the series of signal samples by scaling parameters and sums a plurality of consecutive scaled signal samples, and the nonlinear system elements can transform the output of the linear system elements according to instantaneous nonlinear functions.

The present invention relates to nonlinear signal processing, and, in particular, to adaptive nonlinear filtering of real-, complex-, and vector-valued signals utilizing analog Nonlinear Differential Limiters (NDLs), and to adaptive real-time signal conditioning, processing, analysis, quantification, comparison, and control. More generally, this invention relates to methods, processes and apparatus for real-time measuring and analysis of variables, and to generic measurement systems and processes. This invention also relates to methods and corresponding apparatus for measuring which extend to different applications and provide results other than instantaneous values of variables. The invention further relates to post-processing analysis of measured variables and to statistical analysis. The NDL-based filtering method and apparatus enable improvements in the overall properties of electronic devices including, but not limited to, improvements in performance, reduction in size, weight, cost, and power consumption, and, in particular for wireless devices, NDLs enable improvements in spectrum usage efficiency.

The present invention relates to nonlinear signal processing, and, in particular, to adaptive nonlinear filtering of real-, complex-, and vector-valued signals utilizing analog Nonlinear Differential Limiters (NDLs), and to adaptive real-time signal conditioning, processing, analysis, quantification, comparison, and control. More generally, this invention relates to methods, processes and apparatus for real-time measuring and analysis of variables, and to generic measurement systems and processes. This invention also relates to methods and corresponding apparatus for measuring which extend to different applications and provide results other than instantaneous values of variables. The invention further relates to post-processing analysis of measured variables and to statistical analysis. The NDL-based filtering method and apparatus enable improvements in the overall properties of electronic devices including, but not limited to, improvements in performance, reduction in size, weight, cost, and power consumption, and, in particular for wireless devices, NDLs enable improvements in spectrum usage efficiency.