Microwave Hilbert Transformer and Its Applications in Real-Time Analog Processing

Abstract

A microwave Hilbert transformer is introduced as a new component for Real-time Analog Processing (RAP). In contrast to its optical counterpart, that resort to optical fiber gratings, this Hilbert transformer is based on the combination of a branch-line coupler and a loop resonator. The transfer function of the transformer is derived using signal flow graphs, and two figures of merits are introduced to effectively characterize the device: the rotated phase and the transition bandwidth. Moreover, a detailed physical explanation of its physical operation is given, using both a steady-state regime perspective and a transient regime perspective. The microwave RAP Hilbert transformer is demonstrated experimentally, and demonstrated in three applications: edge detection, peak suppression and single sideband modulation.

Vibration Signal Processing-Based Detection of Short-Circuited Turns in Transformers: A Nonlinear Mode Decomposition Approach

“…The Hilbert Transform (HT) is a lineal operation employed to compute instantaneous amplitude, phase, and frequency of a time series signal. In general, HT converts an input signal x(t) into a signal y(t) applying a convolution between x(t) and the impulse response h(t) = 1/πt, which is defined as [38]:…”

Design of dispersion‐reconfigurable phaser using stepped‐impedance line

“…As the major component in an R‐ASP system, phaser exhibits a frequency‐dependent group delay response, enabling the system to manipulate the instantaneous frequency components of input signal in time domain. Various phasers have been demonstrated in several application scenarios, including the real‐time Fourier transformation, 2 pulse‐position modulation coding system, 3 real‐time spectrum sniffing, 4 Hilbert transformation, 5 and signal‐to‐noise ratio‐enhanced transceiver, 6 corresponding to different group delay dispersion profiles. Therefore, dispersion‐reconfigurable phasers are highly demanded for multifunctional applications.…”

Design of Dispersion-Reconfigurable Phaser using PIN-Diode Loaded Stepped-Impedance Line

“…As the major component in a R-ASP system, phaser exhibits a frequency-dependent group delay response, enabling the system to manipulate the instantaneous frequency components of input signal in time domain. Various phasers have been demonstrated in several application scenarios, including the real-time Fourier transformation [2], pulse-position modulation coding system [3], real-time spectrum sniffing [4], Hilbert transformation [5], and signal-to-noise ratio (SNR)enhanced transceiver [6], corresponding to different group delay dispersion profiles. Therefore, dispersion-reconfigurable phasers are highly demanded for multifunctional applications.…”