Carl E. Baum's research while affiliated with University of New Mexico and other places

Publications (280)

Chapter
Although both HEMP and lightning are threats to aircraft in flight, differences between them occur on several distinct levels of the interaction process. Additionally, the interaction of the external electromagnetic signals with the aircraft’s internal electrical systems depends on many factors. Therefore, to make the interaction analysis tractable...
Article
Recent research has shown that it is possible to kill certain skin cancers by the application of fast, high-amplitude, electromagnetic pulses. An impulse radiating antenna (IRA) with a prolate-spheroidal reflector is one such device that can be employed for this purpose. In this chapter the design of a switch system to launch high-voltage (>100 kV)...
Conference Paper
Full-text available
This paper presents an approach to high power THz generation that uses a Switched Oscillator (SwO) as a photoconductively-switched antenna. A simplified model is used to demonstrate the SwO as an effective THz radiator. Numerical simulations are used to optimize various parameters of interest with the primary objective of maximizing the radiated en...
Article
The accuracy of simplifications to the theory in predicting the fundamental resonant frequency of a wide angle conical antenna was explored by comparing the results obtained based on analytical approximations to experimental results as well as the results of numerical simulation. Good agreement is obtained between the simulated and experimentally m...
Article
This paper provides a holistic view of adverse electromagnetic effects on large electric and electromagnetic systems caused by the High Altitude EMP (HEMP) and/or High Power Electromagnetic (HPM) weapons. For illustration we use systems theory to: assess the interaction between the Electric Power Grid and the Public Data Network; and propose a new...
Article
A configuration for a narrow-band rugged high-power antenna with a horizontally polarized fan-beam radiation pattern is proposed. This antenna is a longitudinal aperture array in the narrow wall of an air-filled rectangular waveguide, and it produces intentional electromagnetic interference for military purposes. It is to be approximately verticall...
Article
This paper briefly reviews the design of a prolate-spheroidal impulse-radiating hyperband antenna system to launch and focus fast (100 ps) high-voltage ( >; 100 kV) pulses onto biological targets. Design and experiments on a graded five-layer dielectric lens, designed to match the pulses into the target medium, are outlined. The design and numerica...
Article
A prolate spheroidal reflector antenna focuses subnanosecond pulsed radiation in the near field with a small beamwidth, allowing for applications such as target detection. Confocal imaging in free space has been demonstrated with such an antenna for both transmitting and receiving. A polarized beam allows for the detection of linear target orientat...
Conference Paper
This paper continues the discussion of the design of an antenna with collinear electric- and magnetic-dipole moments out of phase by approximately π/2 (90°). Using a high-Q approximation, a switched oscillator is matched to the antenna for radiating an oscillatory pulse.
Conference Paper
This paper describes the design and numerical simulations of a switch system to launch fast (100 ps), high-voltage (>100 kV) spherical TEM waves from the first focal point of a prolate-spheroidal impulse-radiating antenna.
Conference Paper
One can suppress the strong signal amplitude of the early-time scattering, relative to the late-time signal containing the natural resonances (for target identification) using various techniques. This paper discusses the use of polarization for the early-time suppression.
Conference Paper
This paper extends the design options for switched oscillators. The oscillator length is increased for a given frequency, up to a full wavelength for the differential version. Multiax cable topology is fundamental to these extensions.
Article
This paper briefly reviews the design of a prolate-spheroidal impulse-radiating antenna system, to launch and focus fast (100 ps) high-voltage (> 100 kV) pulses, as a non-invasive tool for melanoma (skin cancer) treatment. The experiments on a graded five-layer dielectric lens, designed to match the pulses into a biological target medium, are outli...
Article
A design approach to obtain the function defining the bend that minimizes the reflected power into the feed waveguide of a structure, called the H-plane bend radiator (HPB radiator) is presented. The HPB radiator is used as a part of a high-power antenna and therefore there is a requirement for a smooth bend containing no sharp corners. As the smoo...
Article
Design, simulations, and experiments on a radially inhomogeneous spherical dielectric lens, that is used at the second focal point of a prolate-spheroidal impulse radiating antenna, are presented. This lens is designed to match 100-ps pulses into a biological medium. The higher field amplitude and smaller spot size obtained with such a lens are use...
Conference Paper
In searching for various representations of the electromagnetic fields, some recent interest has been placed on the use of path integrals. These in some sense propagate fields from previous times to sometime of interest by all possible spatial paths appropriate to the time difference to the present. This paper reviews some standard formulations and...
Article
Results from analytical calculations, numerical simulations and experiments for a radially inhomogeneous hemispherical dielectric lens are compared in this paper. Such a lens is used at the second focal point of a prolate-spheroidal impulse radiating antenna to match 100 ps pulses in to biological targets.
Article
In this paper we present the experimental results for a five layer electromagnetic focusing lens. This lens is used to match the spherical TEM wave converging at the second focal point of a prolate-spheroidal impulse radiating antenna (PSIRA) into a biological target.
Conference Paper
HPM WBTS (High Power Microwave, Wide-Band Threat Systems) is a high power, repetitively pulsed, wide-band microwave generator. HPM WBTS microwave capability covers the range of 0.2 to 6GHz in nine frequency bands. E-Field specification at target is 30-110 V/m/MHz depending on frequency. The system is transportable, capable of being set up at remote...
Article
Summary form only given. Compact, reliable solid state pulsed power switches can be an enabling technology for many applications. Compact, highspeed switches are needed to reduce the size and weight and improve the reliability of pulse power modulators and pulse forming networks. Methods for achieving the maximum possible performance are dependent...
Article
Summary form only given. The prolate-spheroidal impulse radiating antenna (PSIRA) is used to focus a fast (100 ps), high voltage (> 100 kV) pulse launched from the first focal point onto targets located at the second focal point. These fast electromagnetic pulses with high amplitude are used in various biological applications such as skin cancer tr...
Chapter
Intense, subnanosecond electric fields can be used either to stimulate bioelectric effects, such as calcium release in cells (which can lead to various secondary physiological effects), or to generate local hyperthermia. High power wideband antennas radiating electromagnetic waves in the subnanosecond range allows us to treat deep lesions noninvasi...
Chapter
Impulse-radiating antennas (IRAs) have been used for different applications and the basic motivation for developing IRA systems is to radiate large amplitude, large band ratio, undispersed pulses. This chapter discusses applying fast, high-electric-field pulses without direct contact for killing skin cancer, i.e., to irradiate them using a prolate-...
Chapter
This chapter considers a possible technique for reducing the rise time of high-voltage switches by placing an array of smaller voltage switches in a traveling-wave geometry. This same technique can also be incorporated in a Marx generator. KeywordsSwitch-Marx generator-Traveling wave-Array-Multichannel
Article
A prolate-spheroidal reflector antenna focusing subnanosecond pulsed electromagnetic radiation in the near field is studied. This antenna reflector is fed by a pair of balanced, conical-plate transmission lines and the radiated pulse consists of a prepulse, an impulse, and a postpulse. Whereas the prepulse amplitude decreases inversely with distanc...
Article
Full-text available
Experimental studies of plasma membrane permeabilization, caused by single, intense, submicrosecond square wave pulses, indicate that the product of electric field amplitude and pulse duration (the electrical impulse) can be considered a similarity or scaling factor. A model based on the hypothesis that the intensity of membrane permeabilization ef...
Article
Analytical design procedures, numerical simulations and preliminary experimental results of a dielectric lens concentrating the field on a target are discussed. A quarter spherical electromagnetic lens with subsequent layers is used to obtain better focusing, smaller spot size and elimination of the reflection at the second focal point of a prolate...
Conference Paper
This paper explores a new possible type of high-power mesoband radiator. This consists of a pair of dipoles, one electric and one magnetic, with aligned vectors, but pi/2 (90deg) out of phase. This gives a circular polarization in the far field.
Article
Focusing Impulse Radiating Antennas allow the application of intense electric fields to biological tissue with centimeter spatial resolution. At low electric field strength, the scattered electromagnetic waves from the focal volume can be used to obtain information on the complex permittivity of the tissue at this location. Since the permittivity o...
Article
An electromagnetic lens is designed to obtain better launching for a prolate-spheroidal IRA (PSIRA). Within the lens we have a spherical TEM wave centered on the switch center. However, outside the lens we have an approximate spherical TEM wave centered at the first focal point of the PSIRA.
Article
An effort is underway to determine the electromagnetic (EM) characteristics of hot-wire detonators in order to quantify more precisely how they might respond to modern EM illumination. These analyses provide a precise tailored approach to EM safety and insights into IEEE Standard C95.7-2005. The analyses include a comprehensive investigation of phy...
Article
We have explored the use of a focusing antenna for imaging of targets based on their dielectric properties. At the focal point of the antenna, metal targets with various sizes were placed. A sensor behind the target was used to detect the forward scattered signal. With this system, the minimum dimensions of a target that can be detected are 7 cm, w...
Article
Intense, subnanosecond electric fields can be used either to stimulate bioelectric effects, such as calcium release in cells (which can lead to various secondary physiological effects), or to generate local hyperthermia. High power wideband antennas radiating electromagnetic waves in the subnanosecond range allows us to treat deep lesions non-invas...
Conference Paper
The use of differential high-power sources gives another degree of freedom to antenna design, including two-element arrays. Symmetry considerations are discussed in the context of helical antennas for circular and linear polarizations.
Conference Paper
Symmetry has important consequences for target recognition. Rotation and reflection symmetry for targets near a ground or water surface not only help to identify the targets, but also aid in data processing to increase accuracy. While clutter (other scatterers) interfere with the target signatures, symmetry in the clutter can be used to suppress th...
Conference Paper
Full-text available
Recent research has shown that it is possible to kill certain skin cancers by the application of fast, highamplitude electric-field pulses. It has been suggested that it would be desirable to be able to apply fast, high-electricfield pulses without direct contact for this biological application, i.e., to irradiate them using an antenna from a dista...
Conference Paper
This paper summarizes much information concerning identification of buried targets (mines and unexploded ordnance). This utilizes concepts from the singularity expansion method and symmetry as they appear in the electromagnetic scattering. See the reference list for locating many more references.
Conference Paper
In this paper, we discuss the design procedure of a dielectric lens for better concentrating the fields at the second focus of a prolate-spheroidal IRA to increase the fields and decrease the spot size.
Article
Impulse radiating antennas (IRAs) are designed to radiate very fast pulses in a narrow beam with low dispersion and high field amplitude. For this reason they have been used in a variety of applications. IRAs have been developed for use in the transient far-field region using parabolic reflectors. However, in this paper we focus in the near field r...
Article
This paper considers the use of a spherical array of sources producing a large fast-transient electromagnetic wave near the center of a sphere. For comparison, a lens type of implosion impulse radiating antenna (IRA) is included as an appendix. This complements the prolate-spheroidal focusing-reflector type of IRA, which has been already appearing...
Article
Summary form only given as follows. Simulating a cell's response to applied pulsed electromagnetic fields is difficult because of the great variations of the dimensions involved in the mesh generation process. The membrane thickness is in the nanometer range as compared to the cell dimension which is in microns. For successful simulation the number...
Article
A finite-difference time-domain (FDTD) based simulation to analyze photocurrent generation and wave propagation inside photoconductive semiconductor switch antenna is described. The simulation incorporates the transient field redistribution, carrier generation characteristics, and field acceleration that contribute to the nonlinear behavior of tera...
Article
A biomedical imaging system based on a high power, focusing, wideband antenna system is discussed. It will allow us to record spatial and temporal changes of electrical properties of tissues in the human body, particularly cancerous tissue, which differs greatly in both conductivity and permittivity from healthy tissue. Focusing is achieved by mean...
Article
This paper extends the forward-scattering theorem for a junction of two transmission lines to the case of four transmission lines. The transmission lines are arranged as two pairs, each pair simulating two orthogonal polarizations.
Article
In modeling, the lightning return stroke, one would like to have better knowledge of the closure position of the downward- and upward-propagating leaders. This paper discusses ways to measure this based on electromag- netic-field measurements.
Article
As one uses transient oscillatory sources at high frequencies there is a problem in directly measuring the time-domain waveform (such as in the THz regime). In combining the waveforms from multiple sources there is the problem of the spread of the switching (initiation) times of the waveforms, leading to a lack of coherence (lack of common phase) o...
Article
An effort is underway to determine the electromagnetic (EM) characteristics of hot-wire detonators to quantify the possible effects of EM radiation. The analyses include a comprehensive investigation of physical detonator characteristics, which is then used to model detonators using EM theory and numerical simulations. The theoretical analysis trea...
Article
This paper considers the forward-scattering theorem (in electromagnetics) from the point of view of the scattering from a junction network (lossless) inserted in a transmission line. It is shown that second-order scattering poles can be produced.
Article
Full-text available
Microwave Pulse Compression is a technique for converting a long-duration pulse of microwave power into a pulse with shorter duration and higher amplitude. This is normally implemented by filling a resonant cavity with microwave power, and firing a switch that upsets the cavity resonance, thereby dumping the power. In this paper, we demonstrate pul...
Article
This paper develops some analytical approximations for the transient focal waveform produced at the second focus of a prolate-spheroidal reflector due to a pulse TEM wave launched from the first focus. This is extended to consider the spot size of the peak field near the second focus.
Article
Full-text available
We introduce here a new antenna, the folded horn. This antenna was first proposed by C.E. Baum for radiating high-power mesoband (medium-bandwidth) signals from a very compact package with high efficiency and moderate gain. These antennas are intended to operate at a fre- quency of a few hundred megahertz, for the appli- cation of upsetting electro...
Conference Paper
Many practical multiconductor transmission lines can be considered as random-lay cables in which the wires assume various positions in the transmission-line cross section. This paper considers some of the properties of propagation on such structures. In particular some aspects of such propagation are deterministic in nature. Such conclusions are ba...
Conference Paper
This paper reviews the state of knowledge concerning the identification of buried mines and unexploded ordnance using techniques based on the singularity expansion method, supplemented by symmetry. It includes a list of important references which, in turn, give a very large list of references. This is supplemented by some more recent specific refer...
Conference Paper
The basic design consideration for the physical concept of three different types of increasing permittivity dielectric lens are considered and the optimum number of layers to obtain the required field at the focal point of a prolate-spheroidal IRA based on a plane wave approximation is calculated.
Article
Segmented loops form an appropriate array for a low-impedance magnetic antenna. This paper considers the symmetries of such antennas and the inclusion of pulse-power sources in the total configuration.
Conference Paper
This paper explores some of the design concepts and parameters of electric-dipole antennas driven by high-voltage pulsers, producing mesoband resonant radiating waveforms.
Conference Paper
This paper considers the product integral representing the solution of the propagation on a nonuniform multiconductor transmission line (NMTL). In two parts, we first have the low-frequency power-series solution. Second we have the high-frequency asymptotic solution.
Conference Paper
This paper is a development of the field waveform at the second focus of a prolate-spheroidal reflector and it is an extension of [1],[2]. We explore the analytic behavior of the waveform near the second focal region.
Conference Paper
Full-text available
Summary form only given. By reducing the duration of electrical pulses from microseconds into the nanosecond range, the electric field-cell interactions shift increasingly from the plasma (cell) membrane to subcellular structures. Yet another domain of pulsed electric field interactions with cell structures and functions opens when the pulse durati...
Conference Paper
Since subnanosecond pulses are short compared to the membrane charging time of biological cells, they penetrate the cells, allowing direct electric field interaction with cell substructures. The use of such ultrashort pulses (with risetimes on the order of 100 ps) also provides an opportunity of using antennas, rather than solid electrodes, to deli...
Conference Paper
This paper deals with the numerical and analytical results for the focal waveform of a prolate-spheroidal IRA. Both numerical and analytical calculations are for IRAs with different feed arms. In both cases the comparisons between the numerical and analytical results are presented and discussed.
Article
From the forward-scattering theorem we have relations between the absorption and scattering cross sections, and the forward scattering. The scattered fields are represented by a scattering dyadic times the incident plane wave. This allows one to reformulate the results in terms of the scattering dyadic, exhibiting some general characteristics of th...
Article
Summary form only given. Preliminary research is being conducted to facilitate the development of a system for remotely detonating an IED using directed microwave energy. A detailed understanding of the coupling of electromagnetic energy into the blasting cap of an IED must first be established in order to analyze the interaction of coupled energy...
Article
In the beginning of 1960s, serious attention was paid to the nuclear electromagnetic pulse. This was later extended to conventional high-power electromagnetic sources/antennas. This paper reviews the history in which I played a central part, discussing the major programs, events, and players. The IEEE Transactions On Electromagnetic Compatibility (...
Article
Summary form only given. The use of very high electric fields (~500 kV/cm or higher) with pulse durations in the sub-nanosecond range has been a very recent development in bio-electrics. There appear to be inherent advantages in using short electric pulses such as: (i) negligible thermal heating, (ii) the possibility of selecting the desired time s...
Article
The singularity expansion method (SEM) proposed by Baum1 has been applied to quantify an electromagnetic response in an expansion of complex resonances of the system2.It has been shown that the dominant complex natural resonances of a system are a minimal set of parameters that define the overall physical properties of the system.3 So, a transient...
Article
The JOLT system is a highly directive, impulse-like radiator. The antenna for JOLT is a 10-ft-diameter half-impulse radiating antenna (HIRA). JOLT was one of the first impulse radiating systems to employ a half IRA. For that reason, extensive measurements were made with a prototype, scale model HIRA in order to understand the performance of this cl...
Chapter
Among several possible approaches to the design of lens waveguide transitions is a differential-geometric method. In general one starts with Maxwell’s equations together with boundary conditions and general theorems such as conservation of energy and reciprocity and looks for various mathematical concepts for representing the solution of an EM prob...
Chapter
A general problem, concerning target identification via the late-time aspectindependent complex natural resonant frequencies, is the presence of the large early-time response. It would be advantageous to enhance the late-time response relative to the early-time response. In a general sense this implies some kind of frequency-dependent filter which...
Article
This paper considers the product integration of 2 x 2 matrices by using the quaternion decomposition of such matrices. This gives conditions for the solution in terms of sum integrals. This is applied to the solution of second-order linear differential equations, including the telegrapher equations.
Article
One approach to a transient electromagnetic radiator is an impulse radiating antenna (IRA) [1]. In this case an antenna aperture is focused at infinity. While there are several ways to realize an IRA (reflector, lens, array), the reflector type is very practical, especially for large ones, if electronic beam steering is not required. Basic physical...
Chapter
In processing of electromagnetic scattering data associated with an incident broadband pulse, there is the problem of removing the filtering of this data by the radar antenna(s), the characteristics of the incident pulse, and other electronic equipment (such as directional couplers). One approach to this problem is to construct, transfer functions...
Book
The purpose of the Ultra-Wideband Short-Pulse Electromagnetics Conference series is to focus on advanced technologies for the generation, radiation and detection of ultra-wideband short pulse signals, taking into account their propagation and scattering from and coupling to targets of interest. This Conference series reports on developments in supp...
Conference Paper
In identifying radar targets based on the poles (resonances) in the singularity expansion method (SEM), there is additional information to be gained from the residues. The polarizations of the substructure resonances can also be used as a target signature. In addition, the relative times of arrival of the various resonances at the radar can also be...
Article
This paper is a development of the field waveform at the second focal of a prolate- spheroidal reflector and it is an extension of (1). We explore the analytic behavior of the waveform at the second focal region.
Article
This paper considers the use of dielectric lenses for concentrating a fast pulse on a target (an electromagnetic implosion). There are similarities to and differences from the prolate-spheroidal-reflector case.
Article
This paper gives some insight into how to pump up a resonant cavity for microwave pulse compression. Canonical examples are considered for the resonant modes in rectangular-waveguide cavities, and the appropriate location of coupling ports through which to feed the power into the cavity.
Article
This paper considers the scattering of an inhomogeneous spherical TEM wave emitted from one of two foci of a prolate spheroid (special case of an ellipsoid of revolution). The wave scatters on the inside of a perfectly conducting prolate spheroidal surface to produce an exact inhomogeneous spherical TEM wave propagating toward the second focus. Thi...
Article
In the BLT formalism, based on the electromagnetic topology of a complex system, black boxes (junctions) and multiconductor transmission lines (tubes, especially uniform ones) have long been included. This paper discusses some features, including apertures and cavities in the formalism. This involves the definition of appropriate voltages and curre...
Article
Continuing from a previous paper, the present paper considers an array of such antennas all focused at a common target position. Each antenna, as before, uses a prolate-spheroidal reflector. Now, an array of such antennas introduces the problem of switch spread, since we need the pulses from nearly all the antennas to arrive at the target location...
Article
This paper discusses a concept for high-power microwave antennas based on an array of slots in the sidewall where the electric fields are lower. This gives a polarization which is perpendicular to a plane containing the waveguide axis. By combining two such waveguides one can also suppress grating lobes.
Article
This paper presents a new technique for estimating parameters of damped sinusoids and impulse-like responses utilizing both early and late time transient scattering responses. Transient scattering responses are composed of damped sinusoids at late times and impulse-like components at early times. Due to the impulse-like components, it is difficult...
Article
Wideband and ultrawideband (UWB) technologies have achieved notable progress in recent years, aided immeasurably by improvements in solid-state manufacturing, computers, and digitizers. As a result, wideband systems that were difficult or impossible to implement ten years ago are now being built for an increasingly wide variety of applications incl...
Article
Full-text available
Ultrawideband (UWB) systems that radiate very high-level transient waveforms and exhibit operating bandwidths of over two decades are now in demand for a number of applications. Such systems are known to radiate impulse-like waveforms with rise times around 100 ps and peak electric field values of tens of kilovolts per meter. Such waveforms, if pro...
Article
We consider the detection of subsurface unexploded ordnance via magnetometer and electromagnetic-induction (EMI) sensors. Detection performance is presented, using model-based signal processing algorithms. We first develop and validate the parametric models, using both numerical and measured data. These models are then applied in the context of fea...
Article
Previous papers have considered transient lenses for propagating TEM modes without dispersion. This paper considers the properties of E and H modes in such lenses. The presence of longitudinal field components brings in additional constraints on the allowable coordinate systems, limiting the cases of transient lenses supporting E and H modes to a s...
Article
In the design of high-frequency (or fast-impulse) capacitors required to hold off high voltages, one can use high-dielectric-constant materials (e.g., certain ceramics). This paper considers some of the high-frequency problems of such capacitors and techniques to mitigate them.
Chapter
A recent paper4 considers the physical-optics (PO) approximation for early-time scattering. For axial backscattering examples of perfectly conducting bodies of revolution (BOR), including paraboloids and circular cones, seem to have good PO results as compared to exact and asymptotic results. However, the perfectly conducting angular sector is not...
Chapter
In the singularity expansion method (SEM) one of the hardest things to pin down has been the entire function (in the s = Ω + jω plane). In the time domain, this is an earlytime contribution not representable by complex exponentials (poles). This is discussed in some detail in Ref. 1, which has extensive references. In the present paper we revisit t...
Chapter
If the signal is constrained to last only for a single baud, the optimum signal is the well-known “Prolate Spheroidal Wave Function”1. However, for signals of more than one baud time duration, it is necessary to remove intersymbol interference. There are two common constraints that are used to remove intersymbol interference. The first constraint i...
Article
We describe here the development of an Impulse Radiating Antenna (IRA) through a series of modifications and improvements intended to achieve the following objectives: 1. Improve the Effective Gain 2. Reduce the Cross Polarization Coupling to the Antenna 3. Reduce Reflections (Improve Impedance Match) 4. Improve Mechanical Sturdiness (Make Flight W...
Chapter
In this paper we consider the design of transition regions (EM transient lenses) which serve to transmit waves, ideally with no reflection or distortion, from one transmission line to another. The design is accomplished by specifying the shape and medium of the lens region. The physical properties of these lenses, given by the permeability and perm...

Citations

... The HEMP is a near-instantaneous electromagnetic energy field that is produced by the power and radiation of nuclear events such as the Chernobyl nuclear power plant accident [1]. It poses the most serious threat to various electronic devices or systems on aircraft [2,3]. Hence, it should be given greater consideration during the protection design of the craft. ...
... Electric pulses with a short duration (ns-ps) have been shown to mainly affect intracellular organelles and cause apoptosis, as well as cytoskeletal, nuclear membrane and DNA damage, whilst maintaining an intact plasma membrane (5)(6)(7). According to the time-domain theory (8), psPEF has a wealth of ultra-wideband (UWB) spectrum (almost from direct current up to GHz), therefore it has a higher time and spatial resolution, with little distortion of the signal. If psPEF may be used to target deeper target lesions, without harming the normal tissues, a non-invasive treatment for tumors may be achieved (9). ...
... There exist other coarse-to-fine approaches, which usually include richer classes of basis such as entire functions [37] or matching pursuit [6]. Compared to HRBF, it might be possible to obtain a reconstruction of the same quality with fewer units using these approaches. ...
... Another possibility would have linear (passive and/or active) analog filters. If the early-time signal is sufficiently narrow in time, then special low-pass filters (i.e., integrators [8]) can reduce the early-time amplitude relative to the late-time amplitude. ...
... For mesoband high-power radiators [21] we need appropriate antennas to radiate the energy from some source such as a switched oscillator. Various types are possible [12][13][14][15][16][17][18]20]. Here we consider yet another kind. ...
Citing conference paper
... This demonstrates the plausibility of an antenna as an electric field source for pulsed electric field experiments. Impulse radiating antennas such as the prolate spheroid antenna designed by Baum can constructively focus in the near field to produce strong electric fields [38]. However, when the wave is launched into air it experiences a substantial reflection of energy at the air-aqueous medium interface. ...
... The measurement of THz waveforms is technologically challenging. One approach for resonant waveforms (such as from switched oscillators [2]) involves correlating the waveform with the same waveform appropriately delayed [3]. This involves the measurement of energy in the pulse (approximately damped sinusoidal) ...
... Concurrently, various aspects of EMPs and excessive EM radiation were investigated in the literature, where two most important of them are: modeling of EMP and corresponding EM radiation and assessment [9,10] of its harmful effects [11,27,12,28]. The research related to modeling of EMP and its corresponding EM radiation aims mainly on the determination of the size and shape of the effected area (from the point source of radiation) and estimation of the radiation level in any point of the affected area. ...
... The other method in therapy uses electromagnetic field. This is a non-invasive method [47], where using a coil, antenna or any material can generate an electromagnetic field when current is supplied to the material or object through a generator. In a previous study, Funk et al. found that magnetic field can penetrate cells more deeply than electric field and can also influence chemical and biochemical reactions because the human body is 'semitransparent' to the magnetic field. ...
... There has been a great progress in development, and optimization of impulse radiating antennas (IRA) in recent years. Numerous IRAs with different characteristics such as input impedance, effective gain, field strength and uniformity have been produced [14,15]. The ...