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A time-domain design method for networks with an arbitrary time-domain response is proposed and applied to design a short-pulse differentiator. The proposed method is termed as WAM because it is actually a waveform approach method (WAM) based on the normalized Euclid distance (NED). The NED could naturally characterize the difference between the desired and actual time-domain signals, including their waveforms and amplitudes. The WAM enables the NED to approach zero by tuning the network parameter for the given network topology and thus the actual time-domain response approaches the desired time-domain response. Also, the WAM is utilized to design a short-pulse differentiator with both magnitude and phase responses. Both the theoretical and experimental results verify the feasibility and validity of the WAM. [ABSTRACT FROM AUTHOR]

A high-fidelity short-pulse monopulse antenna based on an extended Goubau line (EGL) is proposed, along with a novel time-domain analyzing and designing method. The monopulse antenna contains a simple feeding network and an EGL radiating structure, where the width of the single conductor is enlarged and a metal wall is constructed along the central line of the conductor. The antenna is actually a two-element array to form sum and difference patterns. Performances of the feeding structure and the EGL are almost independent of operating frequency, ensuring the antenna to transmit and receive short-pulse signals with high waveform fidelity. Angular information is obtained by analyzing the received pulses with the normalized Euclid distance (NED). The NED patterns are plotted to illustrate the angular information provided by the short-pulse monopulse operation. A null depth of 30 dB is obtained by the difference NED pattern for the short pulses with a spectrum from 4.2 to 11.8 GHz. The measured performance shows that the proposed short-pulse monopulse antenna has a promising prospect in directional detecting and tracking applications. [ABSTRACT FROM AUTHOR]

A monopulse feeding network is proposed for transmitting and receiving time-domain short pulse with high fidelity. The network consists of coplanar waveguides (CPWs), slotlines, microstrip lines, and transitions. Both the sum and the differential performances of the network depend mainly on the transverse structures of these transmission lines rather than their lengths, providing the capability of short-pulse transmission with high fidelity. Moreover, the normalized Euclid distance is employed to characterize and optimize the time-domain performance of the proposed network. A prototype is designed, fabricated, and measured, and linear phase response and stable transmission coefficient are achieved in ultrawide bandwidth. Time-domain performances are evaluated using an input differential Gaussian pulse, with a frequency spectrum of 4–12 GHz. The fidelity between input and output signals is over 0.96, and the amplitude of received signals is nearly the same, showing potential in short-pulse monopulse applications of the network. [ABSTRACT FROM AUTHOR]

An ultra‐wideband pulse crossover with a reversed polarity channel is proposed, and a time‐domain analysis is utilized to design the crossover and estimate its performance. Two crossed channels are designed based on post‐wall slotline (PWS) and conventional slotline, and one of the two channels provides an output with reversed polarity. At the overlapping region, the PWS degrades to slotline on single layer to improve isolation between channels. Normalized Euclid distance of short pulses is utilized to evaluate the isolating and polarity reversing features of the crossover, and the matrices of normalized Euclid distance are then obtained and applied to the design procedure. The proposed crossover are modeled and fabricated for simulation and measurement, and the simulated and measured results agree well. Minimum of return loss and isolation is more than 12 dB within an ultra‐wide bandwidth from DC to 8.5 GHz. Moreover, in time domain, the proposed crossover shows good performance in pulse transmission, including high fidelity and amplitude ratio of input and output signals. The characteristics of the crossover indicate the practicability in short pulse application, and rectangular pulse transmission performance is evaluated to verify the ability. [ABSTRACT FROM AUTHOR]

Signal space method for time-domain characterization of short-pulse networks and antennas is presented and described. The short-duration pulses, which are usually recognized as energy signals, belong to the signal space L^2 (\Re) . By means of the signal space analysis, the Euclid distance on L^2 (\Re) is related to fidelity and amplitude ratio, and thus can be used for comprehensively characterizing short-duration pulse waveform distortion and amplitude variation, resulting in an overall description of networks and antennas. Three numerical examples, microstrip transmission line, microstrip pulse power divider, and antipodal Vivaldi antenna, are given to demonstrate the usage and significance of this method for characterization of networks and antennas. [ABSTRACT FROM PUBLISHER]

A time domain objective function based on the normalized Euclidean distance (NED) matrix of general short pulse network is proposed and is employed to optimize a short pulse power divider (PD). The NED matrix is obtained directly from the time domain port signals, which describes the performance of the short pulse networks comprehensively and compactly. Frobenius norm of the difference between the non-optimal and the optimal NED matrix is used as the objective function in the optimization. A short pulse PD is optimized using the proposed NED matrix based objective function and then fabricated. The feasibility and effectiveness of the NED matrix based objective function are validated by the opti mization procedure and the measured results of the short pulse PD. [ABSTRACT FROM PUBLISHER]