Transmission Of Acoustic Energy Research Articles

Modeling and experimental study of non-reciprocal acoustic energy transfer in vibro-acoustic Duffing oscillator

Mechanisms for the nonreciprocal transmission of acoustic energy and the construction of non-reciprocal vibro-acoustic systems have been subjects of intense research in recent years. An experimental study of acoustic nonreciprocal transmission in an experimental system with a nonlinear membrane and two acoustic cavities of different sizes is reported. The membrane can be simplified into a Duffing oscillator, and the asymmetry of the frequency response function of this oscillator is used to realize the non-reciprocal transmission of acoustic energy. The asymptotic solution of the frequency response function of the nonlinear membrane is obtained by the complexification-averaging method. The theoretical simulation results accord well with the experimental results. The results show that the experimental system has a maximum non-reciprocal quantity of 9.1 times in theory, 4.3 times in the experiment, and the normalized frequency bandwidth of the jump phenomenon region is up to 0.56. The research results reveal the mechanism of non-reciprocal transfer of acoustic energy in the experimental system and demonstrate a new way to realize the asymmetric transfer of acoustic energy in an acoustic system with an air medium.

Newly designed solid coupling medium for reducing trapped air pockets during extracorporeal shock wave lithotripsy_ a phantom study

IntroductionAir pockets between the lithotripter head and body surface are almost inevitably generated when applying a handful of gel onto the contact portion of the treatment head and that on the patient’s skin during coupling procedure. These air pockets can compromise the transmission of acoustic energy of shock wave and may significantly affect efficacy of stone disintegration. Comparing to conventional gel, this study aims to investigate efficacy of stone disintegration by using a proprietary isolation-coupling pad (“icPad”) as the coupling medium to reduce trapped air pockets during ESWL procedure.MethodIn this phantom study, Dornier lithotripter (Delta-2 RC, Dornier MedTech Europe GmbH Co., Germany) was used with a proprietary gel pads (icPad, Diameter = 150 mm, Thickness = 4 mm and 8 mm). The lithotripter was equipped with inline camera to observe the trapped air pockets between the contact surface of the lithotripter head. A testing and measuring device were used to observe experimental stone disintegration using icPad and semi-liquid gel. The conventional semi-liquid gel was used as control for result comparison.ResultsThe stone disintegration rate of icPad 4 mm and 8 mm after 200 shocks of energy at level 2 were significantly higher than that of the semi-liquid gel (disintegration rate 92.3%, 85.0% vs. 45.5%, respectively, p < 0.001). The number of shocks for complete stone disintegration by icPad of 4 mm and 8 mm at the same energy level 2 were significantly lower than that of the semi-liquid gel (the number of shocks 242.0 ± 13.8, 248.7 ± 6.3 vs. 351.0 ± 54.6, respectively, p = 0.011). Furthermore, quantitative comparison of observed air pockets under Optical Coupling Control (OCC) system showed that the area of air pockets in semi-liquid group was significantly larger than that of the group using icPad (8 mm) and that of the group using icPad (8 mm) after sliding (332.7 ± 91.2 vs. 50.3 ± 31.9, 120.3 ± 21.5, respectively, p < 0.05).ConclusionThe advantages of icPad includes: (1) reduced the numbers of shock wave and increased stone disintegration rate due to icPad’s superior efficacy; (2) significantly reduce trapped air pockets in ESWL coupling. Due to the study limitation, more data are needed to confirm our observations before human trials.

Analysis of Tire Acoustic Cavity Resonance Energy Transmission Characteristics in Wheels Based on Power Flow Method

As a kind of low-frequency vehicle interior noise, tire acoustic cavity resonance noise plays an important role, since the other noise (e.g., engine noise, wind noise and friction noise) has been largely suppressed. For the suspension system, wheels stand first in the propagation path of this energy. Therefore, it is of great significance to study the influence of wheel design on the transmission characteristics of this vibration energy. However, currently the related research has not received enough attention. In this paper, two sizes of aluminum alloy wheel finite element models are constructed, and their modal characteristics are analyzed and verified by experimental tests simultaneously. A mathematically fitting sound pressure load model arising from the tire acoustic cavity resonance acting on the rim is first put forward. Then, the power flow method is applied to investigate the resonance energy distribution and transmission characteristics in the wheels. The structure intensity distribution and energy transmission efficiency can be described and analyzed clearly. Furthermore, the effects of material structure damping and the wheel spoke number on the energy transmission are also discussed.

Nanofiltration Using Graphene-Epoxy Filter Media Actuated by Surface Acoustic Waves

We exploit the enhancement of liquid transport through a graphene-epoxy film actuated by surface acoustic waves to demonstrate effective and efficient nanoparticle filtration. Unlike previously reported findings using graphene films, the addition of silver epoxy to create a composite film allows higher excitation powers to be sustained over extended operation durations without disintegration of the film such that an increase in the liquid flow rate through the film by up to fourfold can be achieved. Counter to intuition that suggests that the epoxy would fill the interstitial voids between the layers that make up the graphene film so as to reduce the efficiency of liquid transport through the film, we show instead that the higher density and elastic stiffness of the composite film enhances the transmission of acoustic energy into the film that, in turn, leads to more efficient liquid transport through it. Filtration efficiencies above $99$% are obtained for 26-nm particles, decreasing to 99% for 10-nm and 5-nm particulates, which is a significant improvement compared to that obtained with a pure graphene film. While a decrease in filtration rate over time is observed (up to 50% over 3 h of continuous operation) typical to that of graphene and other filter media, the introduction of a simple backwash process allowed for up to 87% recovery of the initial filtration rate. The significant performance enhancement, namely the fourfold increase in throughput, filtration efficiencies of up to 99% for nanoparticles down to 5 nm, and the ability to sustain extended operation at higher powers without disintegration through such a facile and cost-effective modification to the film highlights its potential applicability in practical nanofiltration systems.

A Facile Chemical-Free Cathode Powder Separation Method for Lithium Ion Battery Resource Recovery

• Cathode powder was separated from Al foil using heating and ultrasonic treatment • Ultrasonication greatly improved the removal efficiency • The process was optimized and an applied workflow was suggested • The concentration of valuable metals increased 2-3 fold compared to raw batteries • No harmful chemicals were used during the process The high cost of primary materials and their limited resources, as well as the ever-increasing amount of waste, has magnified the need for recycling and resource recovery from lithium ion batteries (LIB). This need will only be exasperated in the future as personal electronic equipment and electric vehicles (EV) become more widespread. In this study, a simple process for the separation of the cathode materials from waste Apple iPhone 6 lithium batteries is proposed, consisting of thermal treatment followed by ultrasonication. The main advantages of the process are its simplicity and complete independence from all chemicals. Heating the cathode material to 550°C gradually increases the removal efficiency; however, further increase in temperature results in a sharp decline of removal due to changes in the Al foil structure. With limited aeration inside the muffle furnace the removal barely exceeded 60%, whereas under suitable aeration, removal efficiencies exceeding 90% were obtained. Ultrasonication aids the release of cathode powder by creating convective flow as well as intense cavitation. As ultrasonication time and power increase, so does the removal efficiency. However, by increasing the power from 50 W to 100 W, the cathode powder separation efficiency decreases. This is because the numerous cavitation bubbles create a barrier for the transmission of acoustic energy to other parts of the tank, meaning the physical vibration of the transducer is greater than the fluid's ability to stay in contact. The final obtained cathodic powder under optimum conditions (heating for 15 min at 550°C, followed by ultrasonic treatment at 45°C and 50 Watts for 1 min) was 45.5% Co, 4.9% Al, 13.7% Cu, 3.6% Li, and 13.7% Ni.

Band Gaps and Transmission Characteristics Analysis on a Two-Dimensional Multiple-Scatter Phononic Crystal Structure.

In this paper, a novel wrap-around multi-scattering phononic crystal (PC) structure is proposed. Band gaps (BGs) and transmission characteristics of the present structure are calculated using finite element method (FEM). Through the calculations of single-scattering prototype, three complete BGs which are exhibited at low frequency and the fourth wide BG at high frequency are discovered. The transmission features and resonant spectra represented by frequency response function (FRF) shows that apparent resonance directly cause the four specific BGs. By keeping the total area of scatterers unchanged, 2 × 2, 3 × 3 and 4 × 4 scatterers are designed to obtain the change rule of BGs. Furthermore, the size ratio of 2 × 2 scatterers, the number of connection beams are investigated to obtain the regular pattern of acoustic energy transmission and attenuation. The present investigation of multiple-scatter PC structure will provide a solid support on the future design of acoustical functional materials.

Effects of endolymphatic hydrops on acoustic energy absorbance

Background: The presence of endolymphatic hydrops (EH) may cause hearing loss and affect the transmission of acoustic energy to the inner ear.Objectives: Acoustic energy absorbance on wideband acoustic immittance (WAI) was evaluated, focusing especially on EH in the vestibule.Material and methods: A total of 32 ears from 16 patients who underwent 3-T magnetic resonance imaging (MRI) to evaluate the presence of EH were examined, retrospectively. The degree of EH in the vestibule was classified into three grades (no, mild, and significant), and pure tone audiometry (PTA) and WAI were measured before and after a glycerol drip.Results: Ears with significant EH showed significantly higher hearing levels and air-bone gaps (ABG), and higher absorbance values on WAI at low frequencies (560–600 Hz) than ears with mild or no EH. Changes in absorbance values were observed in some ears without threshold change on PTA.Conclusions and Significance: This study showed significantly higher absorbance values of acoustic energy with significant vestibular EH at low frequencies. Considering ABGs observed in ears with significant EH, the presence of EH in the vestibule might cause an obstacle to the transmission of acoustic energy to the inner ear.

Simulation Research on Sparse Reconstruction for Defect Signals of Flip Chip Based on High-Frequency Ultrasound

Flip chip technology has been widely used in various fields. As the density of the solder balls in flip chip technology is increasing, the pitch among solder balls is narrowing, and the size effect is more significant. Therefore, the micro defects of the solder balls are more difficult to detect. In order to ensure the reliability of the flip chip, it is very important to detect and evaluate the micro defects of solder balls. High-frequency ultrasonic testing technology is an effective micro-defect detection method. In this paper, the interaction mechanism between high-frequency ultrasonic pulse and micro defects is analyzed by finite element simulation. A transient simulation model for the whole process of ultrasonic scanning of micro defects is established to simulate scanning in acoustic microscopy imaging. The acoustic propagation path map is obtained for analyzing acoustic energy transmission during detection, and the edge blurring effect in micro-defect imaging detection is clarified. The processing method of the time-domain signal and cross-section image signal of micro defects based on sparse reconstruction is studied, which can effectively improve the accuracy of detection and the signal-to-noise ratio.

An Approach for Diver Passive Detection Based on the Established Model of Breathing Sound Emission

Diver breathing sounds can be used as a characteristic for the passive detection of divers. This work introduces an approach for detecting the presence of a diver based on diver breathing sounds signals. An underwater channel model for passive diver detection is built to evaluate the impacts of acoustic energy transmission loss and ambient noise interference. The noise components of the observed signals are suppressed by spectral subtraction based on block-based threshold theory and smooth minimal statistic noise tracking theory. Then the envelope spectrum features of the denoised signal are extracted for diver detection. The performance of the proposed detection method is demonstrated through experimental analysis and numerical modeling.

Investigation of voice characteristics and their modification in dental prosthetics

Each person's voice is unique. Voice quality is characterized by intelligibility of speech (correlation between voice pitch, volume, timbre and speech speed). Changes in the oral cavity due to tooth loss and resorption of processus alveolaris maxillae or processus alveolaris mandibulae can cause defects in the patient's voice and speech. When using incorrect or functionally low-quality dentures, other changes can be observed, such as skipping, replacing, distorting, adding sounds, as well as nasal speaking. Restrictions or changes in the normal movement of the jaws may interfere with the transmission of acoustic energy through the oral cavity, thereby affecting both the voice characteristics and capabilities, and the balance of the oral resonance. Phonetic adaptation of prosthetic patients depends on the choice and placement of artificial teeth, on the thickness, size and placement of the prosthetic base, optimal tongue space, individual adaptive ability, and the patient's ability to recognize the sound. This report presents the possibilities for maximum restoration of voice characteristics in effective collaboration between the dental team and specialists in otolaryngology and speech therapy.

A Harmonic Dual-Frequency Transducer for Acoustic Cluster Therapy

Acoustic Cluster Therapy (ACT) is a two-component formulation of commercially available microbubbles (Sonazoid; GE Healthcare, Oslo, Norway) and microdroplets (perfluorated oil) currently under development for cancer treatment. The microbubbles and microdroplets have opposite surface charges to form microbubble/microdroplet clusters, which are administered to patients together with a drug. When the clusters and drug reach the target tumour, two ultrasound (US) exposure regimes are used: First, high-frequency (>2.0 MHz) US evaporates the oil and forms ACT bubbles that lodge at the microvascular level. Second, low-frequency (0.5 MHz) US induces stable mechanical oscillations of the ACT bubbles, causing localized micro-streaming, radiation and shear forces that increase the uptake of the drugs to the target tumour. This report describes the design and testing of a dual-frequency transducer and a laboratory setup for pre-clinical in vivo studies of ACT on murine tumour models. The dual-frequency transducer utilizes the 5th harmonic (2.7 MHz) and fundamental (0.5 MHz) of a single piezoceramic disk for the high-frequency and low-frequency regimes, respectively. Two different aperture radii are used to align the high-frequency and low-frequency beam maxima, and the high-frequency –3 dB beam width diameter is 6 mm, corresponding to the largest tumour sizes we expect to treat. The low-frequency –3 dB beam width extends 6 mm. Although unconventional, the 5th harmonic exhibit a 44% efficiency and can therefore be used for transmission of acoustic energy. Moreover, both in vitro and in vivo measurements demonstrate that the 5th harmonic can be used to evaporate the microbubble/microdroplet clusters. For the in vivo measurements, we used the kidneys of non-tumour–bearing mice as tumour surrogates. Based on this, the transducer is deemed suited for pre-clinical in vivo studies of ACT and replaces a cumbersome test setup consisting of two transducers.

The relevance of skull density ratio in selecting candidates for transcranial MR-guided focused ultrasound.

Transcranial MR-guided focused ultrasound (MRgFUS) is a minimally invasive treatment for movement disorders. Considerable interpatient variability in skull transmission efficiency exists with the current clinical devices, which is thought to be dependent on each patient's specific skull morphology. Lower skull density ratio (SDR) values are thought to impede acoustic energy transmission across the skull, attenuating or preventing the therapeutic benefits of MRgFUS. Patients with SDR values below 0.4 have traditionally been deemed poor candidates for MRgFUS. Although considerable anecdotal evidence has suggested that SDR is a reliable determinant of procedural and clinical success, relationships between SDR and clinical outcomes have yet to be formally investigated. Moreover, as transcranial MRgFUS is becoming an increasingly widespread procedure, knowledge of SDR distribution in the general population may enable improved preoperative counseling and preparedness. A total of 98 patients who underwent MRgFUS thalamotomy at the authors' institutions between 2012 and 2018 were analyzed (cohort 1). The authors retrospectively assessed the relationships between SDR and various clinical outcomes, including tremor improvement and adverse effects, as well as procedural factors such as sonication parameters. An SDR was also prospectively obtained in 163 random emergency department patients who required a head CT scan for various clinical indications (cohort 2). Patients' age and sex were used to explore relationships with SDR. In the MRgFUS treatment group, 17 patients with a thalamotomy lesion had an SDR below 0.4. Patients with lower SDRs required more sonication energy; however, their low SDR did not influence their clinical outcomes. In the emergency department patient group, about one-third of the patients had a low SDR (< 0.4). SDR did not correlate with age or sex. Although lower SDR values correlated with higher energy requirements during MRgFUS thalamotomy, within the range of this study population, the SDR did not appreciably impact or provide the ability to predict the resulting clinical outcomes. Sampling of the general population suggests that age and sex have no relationship with SDR. Other variables, such as local variances in bone density, should also be carefully reviewed to build a comprehensive appraisal of a patient's suitability for MRgFUS treatment.

Realization by impedance discontinuity of a unidirectional wave in a duct with harmonically perturbed uniform mean flow.

This paper presents a study of intentionally induced acoustic mode complexity in rigid-walled ducts of separable geometry and with uniform mean flow. An intermediately located perforated plate conceptualized as an impedance discontinuity is employed to maximize the acoustic mode complexity, in turn producing a unidirectional traveling wave from the source to the impedance discontinuity. The impedance of the perforated plate for realization of a unidirectional traveling wave is derived analytically and is found to be a function of the modal wavenumbers, the Mach number of the mean flow, the position of the perforated plate, and the termination impedance. The conditions derived analytically are verified computationally by finite element analysis. A measure of acoustic mode complexity is defined and also evaluated from the finite element analysis. It is found that the realization of a unidirectional traveling wave is robust at low Mach number mean flows, except at the occurrence of resonances. The method presented in this work provides a strategy to control the transmission of acoustic energy in rigid-walled ducts of separable geometry in the presence of uniform mean flow.

Investigation of Broadband Characteristics of Multi-Frequency Piezoelectric Micromachined Ultrasonic Transducer (MF-pMUT)

Multi-frequency ultrasonic transducers are highly promising devices in biomedical applications for providing both good imaging resolution and large detection depth. However, most conventional multi-frequency ultrasonic transducers are designed through integrating multiple single-frequency transducers, with complicated fabrication process, imperfect beam profiles, and limited bandwidths. In this paper, a single-element multi-frequency piezoelectric micromachined ultrasonic transducer (MF-pMUT) is proposed and investigated in terms of broadband property. Three rectangular-diaphragm MF-pMUTs with different length-to-width aspect ratios are fabricated with the microelectromechanical system (MEMS) technology and characterized both in air and underwater. All MF-pMUT samples exhibit at least two broad bands. After optimization of the aspect ratio, two smooth bands with comparable sound pressure level are achieved, providing -6 dB bandwidths of 112%/38% and corresponding central frequencies of 0.615 MHz/1.63 MHz. Benefited from such broadened multi-frequency property and simple structure design, the proposed MF-pMUT shows a great potential in ultrasonic detection, diagnosis, and imaging applications as well as wireless acoustic energy transmission.

Simulation and Experimental Verification of Edge Blurring Phenomenon in Microdefect Inspection Based on High-Frequency Ultrasound

Acoustic micro-imaging based on high-frequency ultrasound has been widely and effectively used for microdefect detection in microelectronic packages. With the miniaturization of microelectronic devices and the reduction of defects, edge blurring occurs in high-frequency ultrasonic scanning and directly affects the detection accuracy and signal-to-noise ratio, especially in spherical structures, such as ball grid arrays, wafer-level chip-scale packaging, and flip-chip solder bumps. This paper depicts the ultrasound interaction behaviors and the edge blurring effects during microdefect imaging, which provide a theoretical basis for improving the defect detection accuracy in subsequent research. A microdefect finite-element model was developed to simulate scanning in acoustic microscopy imaging. C-lines and C-scans of microdefects of various sizes were obtained, which can identify the location and size of the defects more easily. Furthermore, an improved method to obtain the acoustic propagation path map was developed for analyzing the acoustic energy transmission during detection. Different energy consumption paths around the microdefect lead to differences among the C-lines. The different sizes of microdefects show different blurred edges in the C-scans. The experimental data and simulation show consistent results, which prove the credibility of the developed method.

A Review of Low-Intensity Pulsed Ultrasound for Therapeutic Applications.

Ultrasound therapy has a long history of novel applications in medicine. Compared to high-intensity ultrasound used for tissue heating, low-intensity ultrasound has drawn increasing attention recently due to its ability to induce therapeutic changes without biologically significant temperature increase. Low-intensity pulsed ultrasound (LIPUS) is a specific type of ultrasound that delivers at a low intensity and outputs in the mode of pulsed waves. It has minimal thermal effects while maintaining the transmission of acoustic energy to the target tissue, which is able to provide noninvasive physical stimulation for therapeutic applications. LIPUS has been demonstrated to accelerate the healing of fresh fracture, nonunion and delayed union in both animal and clinical studies. The effectiveness of LIPUS for the applications of soft-tissue regeneration and inhibiting inflammatory responses has also been investigated experimentally. Additionally, research has shown that LIPUS is a promising modality for neuromodulation. The purpose of this review is to provide an overview of the recent developments of LIPUS for therapeutic applications, based on the papers that report positive effects, and to present the findings on the understanding of its mechanism. Current available LIPUS devices are also briefly described in this paper.

Piecewise assembled acoustic arrays based on reconfigurable tessellated structures.

Physically reconfigurable, tessellated acoustic arrays inspired by origami structures have recently been leveraged to adaptively guide acoustic energy. Yet, the prior work only examined tessellated arrays composed from uniform folding patterns, so that the limited folding-induced shape change prohibits broad acoustic field tailoring. To explore a wider range of opportunities by origami-inspired acoustic arrays, here, piecewise geometries are assembled from multiple folding patterns so that acoustic transducer elements are reconfigured in more intricate ways upon array folding. An analytical model of assembled geometries and resulting acoustic wave radiation from the oscillating facets is formulated. Using the theoretical tool, parametric investigations are undertaken to study the adaptation of acoustic energy transmission caused by folding and modularity of the array assembly. A proof-of-concept specimen is fabricated and experiments are conducted to validate the theoretical model and to investigate the efficacy of the piecewise acoustic array concept. The total findings reveal that the assembly of tessellated acoustic arrays may emulate the wave radiation emitted by ideal acoustic sources of intricate shapes. Moreover, by exploitation of origami folding actions, the shape adaptations of the proposed arrays permit straightforward wave guiding opportunities for diverse application needs.

A model and experimental approach to the middle ear transfer function related to hearing in the humpback whale (Megaptera novaeangliae).

At present, there are no direct measures of hearing for any baleen whale (Mysticeti). The most viable alternative to in vivo approaches to simulate the audiogram is through modeling outer, middle, and inner ear functions based on the anatomy and material properties of each component. This paper describes a finite element model of the middle ear for the humpback whale (Megaptera novaeangliae) to calculate the middle ear transfer function (METF) to determine acoustic energy transmission to the cochlea. The model was developed based on high resolution computed tomography imaging and direct anatomical measurements of the middle ear components for this mysticete species. Mechanical properties for the middle ear tissues were determined from experimental measurements and published values. The METF for the humpback whale predicted a better frequency range between approximately 15 Hz and 3 kHz or between 200 Hz and 9 kHz based on two potential stimulation locations. Experimental measures of the ossicular chain, tympanic membrane, and tympanic bone velocities showed frequency response characteristics consistent with the model. The predicted best sensitivity hearing ranges match well with known vocalizations of this species.

Measurements of the Relationship Between CT Hounsfield Units and Acoustic Velocity and How It Changes With Photon Energy and Reconstruction Method.

Transcranial magnetic resonance-guided focused ultrasound continues to gain traction as a noninvasive treatment option for a variety of pathologies. Focusing ultrasound through the skull can be accomplished by adding a phase correction to each element of a hemispherical transducer array. The phase corrections are determined with acoustic simulations that rely on speed of sound estimates derived from CT scans. While several studies have investigated the relationship between acoustic velocity and CT Hounsfield units (HUs), these studies have largely ignored the impact of X-ray energy, reconstruction method, and reconstruction kernel on the measured HU, and therefore the estimated velocity, and none have measured the relationship directly. In this paper, 91 ex vivo human skull fragments from two skulls are imaged by 80 CT scans with a variety of energies and reconstruction methods. The average HU from each fragment is found for each scan and correlated with the speed of sound measured using a through transmission technique in that fragment. As measured by the -squared value, the results show that CT is able to account for 23%-53% of the variation in velocity in the human skull. Both the X-ray energy and the reconstruction technique significantly alter the -squared value and the linear relationship between HU and speed of sound in bone. Accounting for these variations will lead to more accurate phase corrections and more efficient transmission of acoustic energy through the skull.

Broadband imaging via direct inversion of blended dispersed source array data

ABSTRACTAlthough seismic sources typically consist of identical broadband units alone, no physical constraint dictates the use of only one kind of device. We propose an acquisition method that involves the simultaneous exploitation of multiple types of sources during seismic surveys. It is suggested to replace (or support) traditional broadband sources with several devices individually transmitting diverse and reduced frequency bands and covering together the entire temporal and spatial bandwidth of interest. Together, these devices represent a so‐called dispersed source array.As a consequence, the use of simpler sources becomes a practical proposition for seismic acquisition. In fact, the devices dedicated to the generation of the higher frequencies may be smaller and less powerful than the conventional sources, providing the acquisition system with increased operational flexibility and decreasing its environmental impact. Offshore, we can think of more manageable boats carrying air guns of different volumes or marine vibrators generating sweeps with different frequency ranges. On land, vibrator trucks of different sizes, specifically designed for the emission of particular frequency bands, are preferred. From a manufacturing point of view, such source units guarantee a more efficient acoustic energy transmission than today's complex broadband alternatives, relaxing the low‐ versus high‐frequency compromise. Furthermore, specific attention can be addressed to choose shot densities that are optimum for different devices according to their emitted bandwidth. In fact, since the sampling requirements depend on the maximum transmitted frequencies, the appropriate number of sources dedicated to the lower frequencies is relatively small, provided the signal‐to‐noise ratio requirements are met. Additionally, the method allows to rethink the way to address the ghost problem in marine seismic acquisition, permitting to tow different sources at different depths based on the devices' individual central frequencies. As a consequence, the destructive interference of the ghost notches, including the one at 0 Hz, is largely mitigated. Furthermore, blended acquisition (also known as simultaneous source acquisition) is part of the dispersed source array concept, improving the operational flexibility, cost efficiency, and signal‐to‐noise ratio.Based on theoretical considerations and numerical data examples, the advantages of this approach and its feasibility are demonstrated.