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Longer titles found: Spike directivity (view), Relative directivity factor (view), Retrodirectivity (view)

searching for Directivity 115 found (208 total)

Horn loudspeaker (4,561 words) [view diff] exact match in snippet view article find links to article

Significant improvements have been made, beginning with the "constant directivity" horn invented in 1975 by Don Keele. The main advantage of horn loudspeakers

Illumination efficiency (793 words) [view diff] exact match in snippet view article find links to article

maximum directivity of an antenna [aperture] to its standard directivity." It is synonymous with normalized directivity. Standard [reference] directivity is

Power dividers and directional couplers (7,280 words) [view diff] exact match in snippet view article find links to article

desired for all directional couplers are wide operational bandwidth, high directivity, and a good impedance match at all ports when the other ports are terminated

Skew (antenna) (165 words) [view diff] exact match in snippet view article

broadcast to four directions each separated 90° from each other. So the directivity of the antenna system resembles a four leaf clover. While settlements

Effective radiated power (3,327 words) [view diff] exact match in snippet view article find links to article

as antenna gain (in a given direction) as compared with the maximum directivity of a half-wave dipole antenna, it creates a mathematically virtual effective

Directional sound (653 words) [view diff] exact match in snippet view article find links to article

called "directional sound" systems. In all wave-producing sources, the directivity of any source, at maximum, corresponds to the size of the source compared

Loudspeaker (12,450 words) [view diff] exact match in snippet view article find links to article

the directivity of a complex shape, based on modeling combinations of point sources, is usually not possible, but in the far field, the directivity of

Genelec (1,308 words) [view diff] no match in snippet view article find links to article

Genelec Oy is a manufacturer of active loudspeaker systems based in Iisalmi, Finland. It designs and produces products for professional studio recording

Vivaldi antenna (619 words) [view diff] exact match in snippet view article find links to article

An example is the Palm Tree Vivaldi Antenna, with greater gain and directivity, used in Near-Field Microwave Biomedical Imaging Applications. Peter

CALM M5 (98 words) [view diff] exact match in snippet view article find links to article

Global (European) 5 GHz spectrum Regulatory domain (border) management Directivity and EMC control Regional DSRC cooperation Multiple radios/interfaces/antenna

Whip antenna (1,928 words) [view diff] exact match in snippet view article find links to article

antennas ⁠1/ 10 ⁠ wavelength long, up to ⁠ 5 /8⁠ wavelength to improve directivity. The most common type is the quarter-wave whip, which is approximately

Rotor–stator interaction (741 words) [view diff] exact match in snippet view article find links to article

predominant role in the noise levels ( P m {\displaystyle P_{m}} ) and directivity, as it will be discussed later. Example For an airplane air-conditioning

D. B. Keele Jr. (412 words) [view diff] exact match in snippet view article find links to article

since the early seventies. He is one of the developers of the constant directivity horn design with several patents of Bi-radial horns from companies like

John M. Eargle (1,337 words) [view diff] exact match in snippet view article find links to article

2001: ... for the concept, design and engineering of the modern constant-directivity, direct radiator style motion picture loudspeaker systems. The work of

Tweeter (3,254 words) [view diff] exact match in snippet view article find links to article

in the horn flare. The horn flare controls the coverage pattern, or directivity, and as an acoustic transformer, adds gain. A professional horn and compression

Wavelet for multidimensional signals analysis (1,785 words) [view diff] exact match in snippet view article find links to article

analysis for multidimensional signals. There also occur challenges such as directivity in multidimensional case. The discrete wavelet transform is extended

Clifford A. Henricksen (3,233 words) [view diff] exact match in snippet view article find links to article

constant-directivity horn) US Patent 4,130,023 (Method and apparatus for testing and evaluating loudspeaker performance Auto-Q directivity measurement

Particle velocity probe (393 words) [view diff] exact match in snippet view article find links to article

band (20 Hz up to at least 10 kHz) linear signal with a figure-of-eight directivity that is proportional to the acoustic particle velocity. Multiple application

Phantom center (245 words) [view diff] exact match in snippet view article find links to article

advantage.[citation needed] Frequency variations can also affect perceived directivity of sound. Therefore the tightness of the stereo field (and hence phantom

Veritone Minimum Phase Speakers (1,138 words) [view diff] exact match in snippet view article find links to article

made them unreliable. Brian Cheney invented and patented a Constant Directivity Wave Guide (CDWG) to increase the horizontal dispersion of the planar

Charlie Hughes (audio engineer) (2,209 words) [view diff] exact match in snippet view article

suit the same end. The QT waveguide, when compared to popular constant directivity (CD) horns, produced about 3–4 dB lower levels of second harmonic distortion

Electro-Voice (1,359 words) [view diff] exact match in snippet view article find links to article

from two channel sources. In 1978, Electro-Voice patented its Constant Directivity Horn, which produced an even balance of frequencies across the listening

Distributed mode loudspeaker (736 words) [view diff] exact match in snippet view article find links to article

low-frequency performance of a traditional loudspeaker, but with a wider directivity and shallower profile, as well as the mid-range and high-frequency performance

Loudspeaker time alignment (1,494 words) [view diff] exact match in snippet view article find links to article

response, improve accuracy and, in non-coaxial drivers, improve the directivity or lobe tilting at the crossover frequencies. It employs adjusting the

Epicenter (1,421 words) [view diff] exact match in snippet view article find links to article

Archived from the original on 2009-02-02. Retrieved 2008-09-14. "What is Directivity?". United States Geological Survey. Retrieved 2018-07-01. Musson, R.

Microstrip antenna (1,509 words) [view diff] exact match in snippet view article find links to article

of equivalent slots. These slots act as an array and have the highest directivity when the antenna has an air dielectric and decreases when it is replaced

Nullcline (308 words) [view diff] exact match in snippet view article find links to article

though with the name ’directivity curve’, was used in a 1967 article by Endre Simonyi. This article also defined 'directivity vector' as w = s i g n

Noise map (682 words) [view diff] exact match in snippet view article find links to article

is the description of noise sources: sound power levels (emission), directivity, working periods. Although some databases can be found, in some cases

Hydrophone (1,276 words) [view diff] exact match in snippet view article find links to article

direct is to use a spherical body around the hydrophone. The advantage of directivity spheres is that the hydrophone can be moved within the water, ridding

Extremely high frequency (2,551 words) [view diff] exact match in snippet view article find links to article

achieve the same high directivity and high gain as larger ones in lower bands. The immediate consequence of this high directivity, coupled with the high

Cabasse (company) (964 words) [view diff] exact match in snippet view article

nineties, Cabasse started to work on coaxial units in order to reduce directivity through spherical wavefront. This is their Spatially Coherent System

1997 Bojnurd earthquake (1,998 words) [view diff] exact match in snippet view article find links to article

from Sheikh, yet the village was destroyed. This was attributed to the directivity of an enhanced shear wave pulse towards the southeast (the rupture direction)

Microwave engineering (1,061 words) [view diff] exact match in snippet view article find links to article

offers distinct advantages in many applications. For instance, sufficient directivity can be obtained using relatively small antennas and low-power transmitters

Thomas J. Russell (398 words) [view diff] exact match in snippet view article find links to article

In 1979 he received a patent based upon the idea of increasing the directivity of a coupler by building the central couplers in a unique configuration

2022 Düzce earthquake (846 words) [view diff] exact match in snippet view article find links to article

Cotton, Fabrice (2023). "Significance of Pulse-Like Ground Motions and Directivity Effects in Moderate Earthquakes: The Example of the Mw 6.1 Gölyaka-Düzce

Weiskirchen transmitter (503 words) [view diff] exact match in snippet view article find links to article

and southeast. By regulation of the feeding power for each mast, the directivity pattern can be changed, in cooperation with Hoher Meissner transmitter

Aromatic compound (2,110 words) [view diff] exact match in snippet view article find links to article

will be added at the ortho, para or meta positions, depending on the directivity of the current substituents to make more complex benzene derivatives

Sound masking (1,280 words) [view diff] exact match in snippet view article find links to article

promotes a spatially uniform delivery of sound, reducing the perception of directivity. As with any commercial-grade sound masking system, an in-plenum sound

Monopole antenna (12,959 words) [view diff] no match in snippet view article find links to article

A monopole antenna is a class of radio antenna consisting of a straight rod-shaped conductor, often mounted perpendicularly over some type of conductive

Critical distance (428 words) [view diff] exact match in snippet view article find links to article

{\gamma V}{RT_{60}}}},} where γ {\displaystyle \gamma } is the degree of directivity of the source ( γ = 1 {\displaystyle \gamma =1} for an omnidirectional

Rhombic antenna (1,102 words) [view diff] exact match in snippet view article find links to article

rhombic can also be used as an HF receiving antenna with good gain and directivity. For example, BBC Monitoring's Crowsley Park receiving station has three

Baffles (submarine) (1,013 words) [view diff] exact match in snippet view article

elements, known as the "end-fire" direction. As a result, have poor directivity in the "end-fire" regions of the array. Sherry Sontag and Christopher

Laser medicine (1,402 words) [view diff] exact match in snippet view article find links to article

subsequently explored. Lasers benefit from three interesting characteristics: directivity (multiple directional functions), impulse (possibility of operating in

2008 Illinois earthquake (1,334 words) [view diff] exact match in snippet view article find links to article

1785/0120100222 He, X.; Zhan, Z.; Zhang, P.; Zhang, D. (2018), "Rupture Directivity of the 18 April 2008 Mt. Carmel, Illinois, Earthquake from Modeling of

Slow-wave coupler (68 words) [view diff] exact match in snippet view article find links to article

velocity of the odd mode of the coupled lines to match that of the even mode, and thereby to improve the isolation and directivity of the coupler. v t e

Sound from ultrasound (3,853 words) [view diff] exact match in snippet view article find links to article

for underwater sonar pulses. The goal of these systems was not high directivity per se, but rather higher usable bandwidth of a typically band-limited

David Gunness (4,409 words) [view diff] exact match in snippet view article find links to article

developed the EV HP series of horn loudspeakers based on the constant directivity (CD) characteristics described by EV engineer Don Keele in the mid-1970s

Free field (acoustics) (484 words) [view diff] exact match in snippet view article

doubling. However if the sound field is not truly free of reflections, a directivity factor Q will help "characterise the directional sound radiation properties

Advanced Multimedia Supplements (394 words) [view diff] exact match in snippet view article find links to article

audio features such as Doppler, size of the source (macroscopicity), directivity and obstruction controlling additional audio effects such as chorus and

Fisheries acoustics (1,771 words) [view diff] exact match in snippet view article find links to article

levels. If the beam pattern and angle to the target are known, this directivity can be compensated for. The need to determine the angle to a target led

L-Acoustics (795 words) [view diff] exact match in snippet view article find links to article

(1995), dV-DOSC modular line source (1999), Kudo with K-Louver variable directivity (2005), P Series self-powered coaxials (2006), SB28 subwoofer with laminar

Tsunami earthquake (1,895 words) [view diff] exact match in snippet view article find links to article

other megathrust earthquakes. These slow rupture speeds lead to greater directivity, with the potential to cause higher run-ups on short coastal sections

Ethylene-vinyl acetate (1,861 words) [view diff] exact match in snippet view article find links to article

in the area around the high frequency speaker driver to give better directivity and sonic imaging. EVA may be used in custom-made dental devices with

Harold Beverage (1,214 words) [view diff] exact match in snippet view article find links to article

1,487,308 Mar 18, 1924 Radio Receiving System - improvements to the directivity of the Beverage Antenna U.S. patent 1,697,945 Jan 8, 1929 Artificial

Rayleigh wave (2,175 words) [view diff] exact match in snippet view article find links to article

structure of the crust. The focal mechanism of the earthquake. The rupture directivity of the earthquake. Local geologic structure can serve to focus or defocus

Halo antenna (2,165 words) [view diff] exact match in snippet view article find links to article

loops. The smaller size is motivated by the desire to sustain the high directivity of the loop's reception null, rather than larger sizes preferred for

John Campbell Brown (741 words) [view diff] exact match in snippet view article find links to article

Archived from the original on 10 March 2010. Retrieved 16 June 2010. "The Directivity and Polarisation of Thick Target X-Ray Bremsstrahlung from Solar Flares"

Network analyzer (electrical) (3,282 words) [view diff] exact match in snippet view article

systematic errors which appear in 1-port reflectivity measurements: Directivity—error resulting from the portion of the source signal that never reaches

1585 Aleutian Islands earthquake (2,291 words) [view diff] exact match in snippet view article find links to article

the megathrust with respect to the Hawaiian Islands allowed for much directivity of the tsunami energy. The results of the model did not rule out the

Helicopter noise reduction (955 words) [view diff] exact match in snippet view article find links to article

on either the advancing or retreating side of the rotor disk and its directivity is characterized by the precise orientation of the interaction. In general

Ari Ben-Menahem (420 words) [view diff] exact match in snippet view article find links to article

earthquake of May 22, 1960, where he introduced the fundamental concepts of 'Directivity' and 'Potency' from which the moment tensor is derived. Since then, rupturing

Harry F. Olson (1,417 words) [view diff] exact match in snippet view article find links to article

838,607 1958 Directional Microphone (Using Two Microphones To Increase Directivity) 2,854,511 1958 Noise Discriminator, Threshold Type 2,645,684 1958 Music

Proximity effect (audio) (907 words) [view diff] exact match in snippet view article

path length difference. This is what gives a directional microphone its directivity.[citation needed] In addition to the angular dependence described above

Vibraphone (5,485 words) [view diff] exact match in snippet view article find links to article

Burroughs, C. B. (1998). The Effects of a Resonator Tube on the Timbre and Directivity of Sound Radiated from a Vibraphone Bar. Pennsylvania State University

Personal RF safety monitor (1,605 words) [view diff] exact match in snippet view article find links to article

any RF personal monitor and can be expressed in two basic parameters: Directivity: Some of them have an isotropic response, which means that they are able

Platonic crystal (815 words) [view diff] exact match in snippet view article find links to article

1063/1.3327813[dead link] M. Farhat; S. Guenneau; S. Enoch (2010), "High directivity and confinement of flexural waves through ultra-refraction in thin perforated

Acoustic lobing (769 words) [view diff] exact match in snippet view article find links to article

height changes. Note: For an individual driver this effect is known as directivity, and is observable in both vertical and horizontal planes, and d is now

Electrostatic loudspeaker (2,864 words) [view diff] exact match in snippet view article find links to article

crossover frequency, such as 500 Hz, has a number of advantages. It reduces directivity to a degree that offers a reasonably wide sweet spot. It allows more

2011 Lorca earthquake (1,527 words) [view diff] exact match in snippet view article find links to article

moderate magnitude earthquake may be explained by the southwestward directivity of a shallow rupture that induced high acceleration values in Lorca village

2018 Hokkaido Eastern Iburi earthquake (2,324 words) [view diff] exact match in snippet view article find links to article

via Twitter. Zang, Chong; Ni, Sidao; Shen, Zhichao (2019), "Rupture Directivity Analysis of the 2018 Hokkaido Eastern Iburi Earthquake and Its Seismotectonic

Curtain array (2,417 words) [view diff] exact match in snippet view article find links to article

shortwave relay stations. This may help one better understand HRS antenna directivity. Targeting Australasia Targeting Indonesia Targeting Latin America This

2-meter band (2,472 words) [view diff] exact match in snippet view article find links to article

receiving station. "Beam antennas" provide substantial increase in signal directivity over ordinary dipole or vertical antennas. Antennas used for distance

Loudspeaker measurement (1,735 words) [view diff] exact match in snippet view article find links to article

in-box measurements, and predicts half-space measurements, but without directivity information. Frequency response measurements are only meaningful if shown

1999 İzmit earthquake (3,988 words) [view diff] exact match in snippet view article find links to article

earthquake. Fault characterization is likewise very relevant to determine the directivity of earthquake waves approaching Istanbul. Modelling of potential impacts

Oceanic dolphin (6,101 words) [view diff] exact match in snippet view article find links to article

for the Bottlenose Dolphin (Tursiops truncatus): Modelling the Receive Directivity from Tooth and Lower Jaw Geometry NATO ASI Series A: Sensory Abilities

Russian opera (4,941 words) [view diff] exact match in snippet view article find links to article

translation of Ivan Dmitrievsky had some elements of the antifeudal directivity. He died in Saint Petersburg in January 1806. Ivan Kerzelli (also known

Russian opera (4,941 words) [view diff] exact match in snippet view article find links to article

translation of Ivan Dmitrievsky had some elements of the antifeudal directivity. He died in Saint Petersburg in January 1806. Ivan Kerzelli (also known

Immersion (virtual reality) (6,358 words) [view diff] exact match in snippet view article

immersion technology can include audio with head-tracking and precise directivity of sound, such as the Nokia OZO technology. The next generation is VIRTSIM

DxOMark (2,517 words) [view diff] exact match in snippet view article find links to article

clipping, user artifacts, other artifacts) For recording only: Background (directivity, noise profile, artifacts) In October 2020, DXOMARK introduced a rating

Yuen Tze Lo (953 words) [view diff] exact match in snippet view article find links to article

1144854. Lo, Y.T.; Lee, S.W.; Lee, Q.H. (August 1966). "Optimization of directivity and signal-to-noise ratio of an arbitrary antenna array". Proceedings

Quill (satellite) (2,836 words) [view diff] exact match in snippet view article

signal-capture area (antenna area) and subsequent narrow-beam receiving directivity were desired. Available facilities with large-dish antennas capable of

Dolphin (15,148 words) [view diff] exact match in snippet view article find links to article

for the Bottlenose Dolphin (Tursiops truncatus): Modelling the Receive Directivity from Tooth and Lower Jaw Geometry NATO ASI Series A: Sensory Abilities

Monitor Audio (1,609 words) [view diff] exact match in snippet view article find links to article

Finite Element Analysis in order to give benefits such as a controlled directivity pattern and increased radiation efficiency. Uniform Dispersion (UD) Waveguide

Animal echolocation (9,683 words) [view diff] exact match in snippet view article find links to article

for the bottlenose dolphin (Tursiops truncatus): modeling the receive directivity from tooth and lower jaw geometry". In Thomas, J. A.; Kastelein, R. A

1985 Algarrobo earthquake (3,569 words) [view diff] exact match in snippet view article find links to article

the ten previous studies shared similar information regarding rupture directivity. They revealed that it primarily ruptured to the south of the epicenter

Studio monitor (3,983 words) [view diff] exact match in snippet view article find links to article

The British Broadcasting Corporation "The Influence of Loudspeaker Directivity and Orientation on the Effective Audience Area in Two-Channel Stereophonic

Melvin M. Weiner (1,223 words) [view diff] exact match in snippet view article find links to article

Letters, Vol. 28, No. 25, p. 2329 (1992). "Radiation Efficiency and Directivity of Monopole Elements with Disk Ground Planes on Flat Earth," Electronics

Laser ultrasonics (2,644 words) [view diff] exact match in snippet view article find links to article

, 38, 677-679, 1981. D.A. Hutchins, R.J. Dewhurst and S.B. Palmer, "Directivity patterns of laser-generated ultrasound in aluminium",J. Acoustic Soc

Prism Ark (2,287 words) [view diff] exact match in snippet view article find links to article

(リッテ·ラートゥス, Ritte Rātusu) Voiced by: Kimiko Koyama Weapon: Bud and Fys (Directivity Automagically Floating Prism) A teacher in the academy. She also teaches

Sonar (12,476 words) [view diff] exact match in snippet view article find links to article

the array gain of the receiving array (sometimes approximated by its directivity index) and DT is the detection threshold. In reverberation-limited conditions

Sound reinforcement system (8,369 words) [view diff] exact match in snippet view article find links to article

pp. 426–54 (196). Meyer, D., "Digital Control of Loudspeaker Array Directivity", J. Audio Engineering Society, volume 32, number 10 (1984). Peutz, V

Graphene plasmonics (1,515 words) [view diff] exact match in snippet view article find links to article

"Ultracompact Graphene-Assisted Tunable Waveguide Couplers with High Directivity and Mode Selectivity". Scientific Reports. 8 (1): 13362. Bibcode:2018NatSR

Line array (2,451 words) [view diff] exact match in snippet view article find links to article

about 10°. A well-designed spiral array could have an almost constant directivity pattern with frequency, with some small lobes exhibited at low frequencies

Earthquake casualty estimation (4,812 words) [view diff] exact match in snippet view article find links to article

introduced by variations of magnitude for M<8, soil conditions, and directivity of energy radiated. Other inaccuracies in data sets or input contribute

Long-range acoustic device (7,798 words) [view diff] exact match in snippet view article find links to article

multiplied by the speaker radius, is often used to characterize sound source directivity. For this source, ka=19 at 2.5 kHz, and according to the LRAD data sheet

Academy Award for Technical Achievement (280 words) [view diff] exact match in snippet view article find links to article

Holman has been involved in the research and integration of the constant-directivity, direct radiator bass type of cinema loudspeaker systems. Sound To Geoff

Metamaterial (10,792 words) [view diff] exact match in snippet view article find links to article

negative permeability allow for properties such as small antenna size, high directivity and tunable frequency. A metamaterial absorber manipulates the loss components

Action potential (16,455 words) [view diff] exact match in snippet view article find links to article

599–601 Aur D, Connolly CI, Jog MS (November 2005). "Computing spike directivity with tetrodes". Journal of Neuroscience Methods. 149 (1): 57–63. doi:10

Last mile (telecommunications) (3,752 words) [view diff] exact match in snippet view article

sharing users and each user must have large antenna, with attendant directivity and pointing requirements, in order to obtain even modest information-rate

Actualizing tendency (2,033 words) [view diff] exact match in snippet view article find links to article

Humanistic psychology Organismic theory Levitt, B. E. (2005) Embracing non-directivity: reassessing person-centered theory and practice in the 21st century

2020 Aegean Sea earthquake (6,660 words) [view diff] exact match in snippet view article find links to article

"The 2020 Samos (Aegean Sea) M7 earthquake: a normal fault with rupture directivity and near surface slip explaining the tsunami generation and coastal uplift"

High Resolution Wide Swath SAR imaging (2,713 words) [view diff] exact match in snippet view article find links to article

(1 m), combines the capabilities of digital beamforming with the high directivity of a large reflector antenna. The reflector based architecture offers

Subwoofer (13,931 words) [view diff] exact match in snippet view article find links to article

2011. Retrieved April 28, 2010. "Forward Steered Arrays in Precision Directivity Speaker Systems". Technical Notes. Northridge, California: JBL Professional

List of Panasonic camcorders (6,364 words) [view diff] exact match in snippet view article find links to article

revised, and the new model features better (though nowhere near perfect) directivity of the recorded sound. Each camcorder also features an accessory shoe

Ulmas Mirsaidov (2,142 words) [view diff] exact match in snippet view article find links to article

reveal and justify mechanism, behavior regularity and many reactions directivity. He is a great propagandist of science history. In his works Prezidenti

Sensor array (2,823 words) [view diff] exact match in snippet view article find links to article

\lambda /2} . However, the width of the main beam, i.e., the resolution or directivity of the array, is determined by the length of the array compared to the

Tom Danley (2,820 words) [view diff] exact match in snippet view article find links to article

bandpasses are combined into one horn to make a phase-accurate, constant-directivity single-point-source loudspeaker. Danley's Tapped Horn concept directs

Ring laser (5,335 words) [view diff] exact match in snippet view article find links to article

regular (linear) lasers features like extreme monochromaticity and high directivity, it differs in its inclusion of an area. With the ring laser, one could

Virtual reality applications (10,615 words) [view diff] exact match in snippet view article find links to article

an immersive listening experience. through head-tracking and precise directivity of sound. In 2015, roller coasters and theme parks began to incorporate

LED tube (2,479 words) [view diff] exact match in snippet view article find links to article

directed in a narrower beam to wherever the light is required. Owing to the directivity and good luminous efficacy, LED tubes provide illuminance equal to that

List of longwave radio broadcasters (245 words) [view diff] exact match in snippet view article find links to article

Rás 1 RÚV Rás 2 Iceland Gufuskalar near Hellissandur Slight oval bi-directivity aerial, top loaded parallel connected triangular loops, mast as a common

Project Artemis (5,283 words) [view diff] exact match in snippet view article find links to article

investigation was whether an active system could be developed with the power and directivity to exploit ocean zones the passive system being installed might not.

ASV Mark III radar (8,635 words) [view diff] exact match in snippet view article find links to article

removed to dive. Fliege offered not only reception but also reasonable directivity, allowing it to provide initial aiming for the anti-aircraft guns. A

Jean-Louis Steinberg (1,631 words) [view diff] exact match in snippet view article find links to article

launched in 1971. The experiment successfully showed for the first time the directivity of solar radio bursts of Types I and III. A similar experiment for detection

Physics of whistles (12,651 words) [view diff] exact match in snippet view article find links to article

presence of the supersonic jet structure, which can strongly modify the directivity. The original equation of Hartmann is shown below: λ d = 5.8 + 2.5 (