Broad Beam Research Articles

A Comparative Study on the Shielding Calculation Methods for an Optimal Shielding Design of Isolation Rooms in a Nuclear Medicine Facility in the Philippines Providing 131I Thyroid Ablation Therapy.

Iodine-131 (131I) has been used widely in diagnosing and treating thyroid disorders, but its radioactive nature poses risks of gamma radiation exposure to those near the patient. To mitigate this, radiation protection measures are needed, among which is the provision of optimal structural shielding. In the Philippines, achieving this involves using minimum shielding thickness to meet safety limits from national regulations. Widely used conventional methods, like those based on the tenth-value layer (TVLs) measurements, may yield poor estimates, while computational simulations are precise but impractical to use due to their complexity. Archer's fitting method offers a simple and accurate alternative for designing optimal shielding in medical imaging and radiotherapy facilities based on multiple studies. However, little to no data is available regarding the use of Archer's fitting method in providing better accuracy in shielding calculations in isolation rooms of 131I therapy facilities. A comparison of the transmission factors calculated using different calculation methods was done, and their effect on the minimum shielding thicknesses was investigated. Transmission curves generated with broad-beam TVLs reported from previous studies yielded the closest agreement with ANS/ANSI 6.4.3 buildup factors for lead barriers. On the other hand, results showed the closest agreement among the transmission curves and shielding thicknesses acquired with the American National Standard (ANSI/ANS) 6.4.3. buildup factors, Archer's fitting method, and Monte Carlo simulation through Particle Heavy Ion Transport System (PHITS) ver. 3.28 code for ordinary concrete barriers. Poor agreement was seen with the curves generated with the Narrow-Beam and Ideal Broad Beam TVL methods and the curve generated with ANSI/ANS 6.4.3. buildup factor data. Broad-Beam TVLs from previous studies, Monte Carlo Simulation, and Archer's fit can be alternative options for shielding design. An experimental study is proposed for verification.

On the Morphological Evolution with Cycling of a Ball-Milled Si Slag-Based Electrode for Li-Ion Batteries

A Si/SiC/SiO2 (53/44/3 wt.%) composite is evaluated as an anode material for Li-ion batteries. This material, a result of the high-energy ball-milling of a by-product of the carbothermal reduction of silica (Si slag), is predominantly made up of micrometric particles of amorphous or short-range order Si in which submicrometric SiC inclusions are dispersed. Its capacity is 860 mAh g−1 (1.7 mAh cm−2) after 200 cycles in half-cell configuration and 1.6 mAh cm−2 after 70 cycles in full-cell. The SiC component is not electroactive for lithiation but plays a key role in the electrode stability by preventing the formation of the c-Li15Si4 phase, known to accelerate electrode degradation. It is shown that capacity decay with cycling mainly originates from solid electrolyte interphase (SEI) growth rather than particle disconnections. Complementary wide angle X-ray scattering (WAXS) analyses confirm the SEI grows alongside cycling and allows for the highlighting of its major components, namely, Li2CO3 and LiF. The morphological evolution of the electrode upon cycling is studied by electrochemical dilatometry, operando optical microscopy, and focused ion beam (FIB) and broad ion beam (BIB) scanning electron microscopy (SEM). No particle cracking is observed. However, reconstructed 3D imaging of the electrodes before and after 10 and 200 cycles clearly shows that the particles progressively evolve a dendritic structure. The SEI grows on and within the particles and induces a significant decrease in the electrode’s porosity and an increase in its thickness.

Fabrication of shallow EUV gratings on silicon by irradiation with helium ions

To accurately achieve structure height differences in the range of single digit nanometres is of great importance for the fabrication of diffraction gratings for the extreme ultraviolet range (EUV). Here, structuring of silicon irradiated through a mask by a broad beam of helium ions with an energy of 30 keV was investigated as an alternative to conventional etching, which offers only limited controllability for shallow structures due to the higher rate of material removal. Utilising a broad ion beam allows for quick and cost effective fabrication. Ion fluence of the irradiations was varied in the range of 1016 ... 1017 ions · cm-2. This enabled a fine tuning of structure height in the range of 1.00 ± 0.05 to 20 ± 1 nm, which is suitable for shallow gratings used in EUV applications. According to transmission electron microscopy investigations the observed structure shape is attributed to the formation of point defects and bubbles/cavities within the silicon. Diffraction capabilities of fabricated elements are experimentally shown at the SX700 beamline of BESSY II. Rigorous Maxwell solver simulation based on the finite-element method and rigorous coupled wave analysis are utilised to describe the experimental obtained diffraction pattern.

Shielding resources for four common radiopharmaceuticals utilized for imaging and therapy: Tc-99m, F-18, I-131, and Lu-177.

The use of radioactive materials in the United States has been tightly regulated by the Nuclear Regulatory Commission and other entities for many decades. In 2015, however, the Joint Commission began to require hospital-based nuclear medicine departments to conduct shielding designs and evaluations for radioactive material areas, mirroring established x-ray practices. NCRP Report No. 147 guides diagnostic medical x-ray shielding, but obviously cannot be used alone for nuclear medicine applications. The rising demand for theranostic nuclear medicine shielding evaluations particularly necessitates updated focused guidance, the aim of this report. Monte Carlo simulations were conducted using GATE software to analyze the effects of various barriers on the transmission of radioactive emissions. The simulations used point sources of Tc-99m, F-18, I-131, and Lu-177 and evaluated dose deposition to blocks of tissue using Dose Actors. Different ceiling heights (ranging from 10-16 feet) were also tested for scattering effects. The Archer equation was employed to fit transmission curves and estimate required barrier thicknesses. Broad beam transmission factors and Archer fitting parameters are reported for various materials including lead, gypsum, concrete (light weight and normal weight), glass, and steel. A sample shielding calculation is provided for a wall separating Lu-177 dotatate patients from an adjacent office to maintain public dose limits. Relevant occupancy factors are also provided. While Lu-177 has a relatively low exposure rate constant, shielding may be necessary for high-volume therapies like Lu-177 DOTATATE and Lu-177 vipivotide tetraxetan PSMA. Shielding involves accounting for broad radiation beams and requires thorough characterization of radiation buildup. When shielding to the typical height of 7 feet, scatter from ceilings and floors is negligible for transmission above 10%, but severely limits the ability to shield for transmission below 1%.

Modeling and design of compact, permanent-magnet transport systems for highly divergent, broad energy spread laser-driven proton beams

Modeling and design of compact, permanent-magnet transport systems for highly divergent, broad energy spread laser-driven proton beams

The Combination of Temporal and Spatial Dose Fractionation in Microbeam Radiation Therapy.

Background: Microbeam radiation therapy (MRT) is an advanced preclinical approach in radiotherapy that utilizes spatially fractionated dose distributions by collimating x-rays into micrometer-wide, planar beams. While the benefits of temporal fractionation are well established and widely incorporated into conventional radiotherapy protocols, the interplay between MRT and temporal dose fractionation remains largely unexplored. In this study, we investigate the effects of combining temporal and spatial dose fractionation by assessing clonogenic cell survival following temporally fractionated MRT with varying irradiation angles, compared to conventional broad-beam (BB) irradiation. Methods: A lung tumor cell line (A549) and a normal lung cell line (MRC-5) were irradiated with a total number of four fractions with a 24 h interval between each fraction. We compared a temporally fractionated BB regime to two temporally fractionated MRT schemes with either overlapping MRT fields or MRT fields with a 45° rotation per fraction. Subsequently, the clonogenic cell survival assay was used by analyzing the corresponding survival fractions (SFs). Results: The clonogenic survival of A549 tumor cells differed significantly between microbeam radiation therapy with rotation (MRT + R) and overlapping MRT. However, neither MRT + R nor overlapping MRT showed statistically significant differences compared to the broad-beam (BB) irradiation for A549. In contrast, the normal tissue cell line MRC-5 exhibited significantly higher clonogenic survival following both MRT + R and overlapping MRT compared to BB. Conclusions: This study demonstrates that combining temporal and spatial fractionation enhances normal tissue cell survival while maintaining equivalent tumor cell kill, potentially increasing the therapeutic index. Our findings support the feasibility of delivering temporally fractionated doses using different MRT modalities and provide clear evidence of the therapeutic benefits of temporally fractionated MRT.

Impact of broad ion beam center alignment and mask position on Si wafer cross-section milling rate

When processing an area over 500 µm in sample cross-section processing using an ion beam, Ar broad ion beam (Ar BIB) is used. Place a mask over the sample to be cross sectionized and irradiate Ar BIB on the specimen set higher than the mask. As the mask is cut, the cross section is processed in a form that follows the cross section. In the case of commercially available equipment based on Si wafer, the height on the specimen is set within 100 um above the mask, and the milling rate is defined as the result of processing for 1 h. It is generally known that during BIB processing, half of the beam is irradiated to the mask, and the remaining half is irradiated to the specimen for processing. However. in this study, it was found that the milling rate increased whenever the center of the beam was raised on the mask little by little (within a few ums to 100 um). From this study, the irradiation position of the BIB was raised on the mask surface at regular intervals for the experiment, and through this, the definition of the beam size of the DC plasma ion gun was used in the experiment, and the change in the milling rate of the Si wafer was studied.

Comprehensive assessment of broad beam transmission factors for nuclear medicine shielding.

Comprehensive assessment of broad beam transmission factors for nuclear medicine shielding.

Synchrotron-based infrared microspectroscopy unveils the biomolecular response of healthy and tumour cell lines to neon minibeam radiation therapy.

Radioresistant tumours remain complex to manage with current radiotherapy (RT) techniques. Heavy ion beams were proposed for their treatment given their advantageous radiobiological properties. However, previous studies with patients resulted in serious adverse effects in the surrounding healthy tissues. Heavy ion RT could therefore benefit from the tissue-sparing effects of minibeam radiation therapy (MBRT). To investigate the potential of this combination, here we assessed the biochemical response to neon MBRT (NeMBRT) through synchrotron-based Fourier transform infrared microspectroscopy (SR-FTIRM). Healthy (BJ) and tumour (B16-F10) cell lines were subjected to seamless (broad beam) neon RT (NeBB) and NeMBRT at HIMAC. SR-FTIRM measurements were conducted at the MIRAS beamline of ALBA Synchrotron. Principal component analysis (PCA) permitted to assess the biochemical effects after the irradiations and 24 hours post-irradiation for the different RT modalities and doses. For the healthy cells, NeMBRT resulted in the most dissimilar spectral signatures from non-irradiated cells early after irradiations, mainly due to protein conformational modifications. Nevertheless, most of the damage appeared to recover one day post-RT; conversely, protein- and nucleic acid-related IR bands were strongly affected by NeBB 24 hours after treatment, suggesting superior oxidative damage and nucleic acid degradation. Tumour cells appeared to be less sensitive to NeBB than to NeMBRT shortly after RT. Still, after one day, both NeBB and the high-dose NeMBRT regions yielded important spectral modifications, suggestive of cell death processes, protein oxidation or oxidative stress. Lipid-associated spectral changes, especially due to the NeBB and NeMBRT peak groups for the tumour cell line, were consistent with reactive oxygen species attacks.

Micromorphological features of brown rotted wood revealed by broad argon ion beam milling.

Brown rot fungi, the major decomposers in the boreal coniferous forests, cause a unique wood decay pattern but many aspects of brown rot decay mechanisms remain unclear. In this study, decayed wood samples were prepared by cultivation of the brown rot fungi Gloeophyllum trabeum and Coniophora puteana on Japanese coniferous wood of Cryptomeria japonica, and the cutting planes were prepared using broad ion beam (BIB) milling, which enables observation of intact wood, in addition to traditional microtome sections. Samples were observed using field-emission SEM revealing that areas inside the end walls of ray parenchyma cells were the first to be degraded. Osmium reaction precipitates were observed in the degraded regions, as well as in plasmodesmata. In the cell wall where ray parenchyma cells contacted with the tracheids, specific degradation of cross-field pits and hyphal elongation into this area was observed in degradation by both fungi. Other pit types were also degraded as noted in previous studies. Delamination between the S1 and S2 layers of tracheids, and cracks in the tracheid cell walls were observed. These findings provide new insights into the cell wall degradation mechanisms during the incipient stages of brown rot decay.

Standard requirements for clinical very high energy electron and ultra high dose rate medical devices

Very High-Energy Electrons (VHEE) present a promising innovation in radiation therapy (RT), particularly for the treatment of deep-seated tumors using Ultra High Dose Rate (UHDR) within the framework of FLASH-RT. VHEE offers significant advantages, such as improved tumor targeting, reduced treatment times, and potential utilization of the FLASH effect, which may minimize normal tissue toxicity. However, the lack of an international technical standard for VHEE systems, especially for UHDR applications, remains a critical challenge. Current standards for radiation therapy equipment, such as IEC 60601-2-1 and IEC 60601-2-64, do not encompass VHEE technology. This regulatory gap underscores the need for developing a structured international standard to ensure the basic safety and essential performance of VHEE medical devices. Addressing this challenge requires overcoming complex dose delivery issues, such as the interaction of multiple fields and beam conformality and incorporating novel techniques like broad beam or pencil beam scanning. Establishing comprehensive regulatory standards is essential to ensure patient safety, consistent treatment practices, and the successful clinical integration of VHEE systems. These standards must encompass design guidelines, radiation protection protocols, and integration with existing oncology practices. Collaborative research and development efforts are crucial to formulating evidence-based guidelines, fostering the safe and effective use of VHEE in clinical settings. By addressing these challenges, VHEE technology has the potential to revolutionize cancer therapy, particularly for deep-seated tumors, while enhancing therapeutic outcomes for patients.

In-Situ Charging-Discharging SEM Observation and Analysis for Si Anode in a Solid-State Battery~ Cross-Section Preparation and in-Situ SEM Observation By Stack Pressure Holder ~

Next-generation solid-state batteries are expected to offer improved capacity and safety. The increase in capacity depends on the negative electrode material, and high-capacity materials such as Si, which can absorb large amounts of Li, are the subject of research. The amount of Li transferred can be measured electrically. However, it has not been possible to visualize where Li is distributed within the anode particles or to analyze the chemical state of the anode particles in real-time.In-situ observation and analysis of sample cross sections using a scanning electron microscope (SEM) are effective in analyzing the behavior and chemical state of Li introduced into the Si anode and the interface state between the solid electrolyte and the anode during charge-discharge. During charging and discharging, the Si anode undergoes a threefold or greater volume expansion and contraction due to Li absorption and desorption, cutting off the ionic conduction path, so it is necessary to apply a sample stacking pressure to suppress the volume expansion. A stack pressure holder is designed for operando experiments of solid-state batteries in an SEM. This holder enables smooth cross-sectioning using a broad Ar ion beam and in-situ SEM observation while applying uniform pressure which minimizes the resistance across interfacial boundaries. It also reduces the risk of specimen breakage because it fixes the sample throughout the entire air-isolated workflow, from cross-section preparation to real-time observation in the SEM.Si anode composites were made by mixing Si particles, argyrodite sulfide solid electrolyte (SSE), and acetylene black (AB). The cathode composite was made by mortar mixing the ternary oxide cathode material LiNi1/3Mn1/3Co1/3O2 (NMC), SSE, and AB. Each component was put into a pelletizer, stacked, and pressurized at about 500 MPa to produce a full cell pellet. The pellet was cut into 4.8 mm squares using a precision punching tool for highly brittle materials (NOGAMIGIKEN, NC-CE-SS) and placed on the stack pressure holder, where a pressure of 25 MPa was applied. The cross-sections were prepared with an Ar ion beam (acceleration voltage: 5 kV, cooling temperature: -120 °C, processing time: 5 hr) using a cross-section preparation system (JEOL, Cooling Cross Section PolisherTM, IB-19520CCP) while applying stack pressure. In order to minimize sample deterioration due to exposure to the atmosphere, glove boxes and transfer vessels that can be closed to the atmosphere were used for the entire process from pretreatment to processing to observation. Samples transported to the SEM in the stack pressure holder were charged and discharged at 0.2C (SOC vs. NMC reference) by a charge/discharge device (MEIDEN HOKUTO, Hz-Pro).The observation results of the charge-discharge process on a cross-sectional sample under stack pressure using this holder are shown in Fig. 1. (a) shows the backscattered electron (BSE) composition image near the interface between the Si anode and SSE and the interface and Si anode particles are clearly observed. (b) shows the charge-discharge curve in this experiment, and (c) shows the BSE composition image after 30 minutes of charging (SOC 10% vs. NMC reference), in which the composition contrast of the Si negative electrode particles gradually changes from the solid electrolyte side due to Li absorption during charging. In the experiment, the sample was maintained at a fixed holding pressure from the time of CP cross-section processing to the SEM observation without changing the holder, and it can be assumed that the observed behavior is similar to the actual behavior. Energy dispersive X-ray spectroscopy (EDS) and soft X-ray spectroscopy (SXES) can also be performed during in-situ charge-discharge observations to obtain elemental distribution and chemical state analysis of lithium and Si. The changes in microstructure of the battery cross-section can also be captured, and the chemical state analysis and the evaluation of the optimum stack pressure at the pressures up to 50 MPa can be expected.AcknowledgmentsWe would like to thank Professor Nobuya Machida of Konan University for cooperation in some of the battery sample preparation. Figure 1

Comprehensive study of rapid capacity fade in prismatic Li-ion cells with flexible packaging

Prismatic lithium-ion batteries (LIBs) are considered promising electric energy sources in electromobility applications due to their efficient space utilization. However, their sensitivity to external and internal influences and reduced durability lead to inflation risk and potential explosions throughout their lifecycle. These critical processes are strongly influenced by the inner construction of the cell, especially concerning the coating and mechanical fixation. This study subjects a commercially available prismatic LIB cell to comprehensive, correlative analysis employing various imaging techniques. The inner structure of the entire cell is visualized non-destructively by X-ray computed tomography (CT), enabling the identification of critical design flaws prior to electrochemical cycling. Electrochemical cycling simulates the battery lifecycle, and the cell is subsequently disassembled in the fully charged state. The usage of the inert-gas transfer system allowed the preparation of Broad Ion Beam (BIB) electrodes cross-sections in a fully native state and for the first time to observe the tearing of graphite particles due to over-lithiation. Established region labeling system allowed to use CT and scanning electron microscopy (SEM) correlatively to identify critical regions. After 100 cycles, a 40% capacity loss was observed and event diagram describing deagradation mechanisms, related both to the cell design and to the processes occurring at high load, was created.

The Impact of Synchrotron Microbeam Radiation Therapy Combined With Broad Beam in a Preclinical Breast Cancer Model

The Impact of Synchrotron Microbeam Radiation Therapy Combined With Broad Beam in a Preclinical Breast Cancer Model

Retraction Note: Investigation on broad beam pattern synthesis

The article was submitted to be part of a guest-edited issue. An investigation by the publisher found a number of articles, including this one, with a number of concerns, including but not limited to compromised editorial handling and peer review process, inappropriate or irrelevant references or not being in scope of the journal or guest-edited issue. Based on the investigation's findings the publisher no longer has confidence in the results and conclusions of this article. The author did not respond to correspondence from the publisher regarding this retraction. Publisher's note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Hybrid ultra-high and conventional dose rate treatments with electrons and photons for the clinical transfer of FLASH-RT to deep-seated targets: A treatment planning study

PurposeThis study explores the dosimetric feasibility and plan quality of hybrid ultra-high dose rate (UHDR) electron and conventional dose rate (CDR) photon (HUC) radiotherapy for treating deep-seated tumours with FLASH-RT. MethodsHUC treatment planning was conducted optimizing a broad UHDR electron beam (between 20–250 MeV) combined with a CDR VMAT for a glioblastoma, a pancreatic cancer, and a prostate cancer case. HUC plans were based on clinical prescription and fractionation schemes and compared against clinically delivered plans. Considering a HUC boost treatment for the glioblastoma consisting of a 15-Gy-single-fraction UHDR electron boost supplemented with VMAT, two scenarios for FLASH sparing were assessed using FLASH-modifying-factor-weighted doses. ResultsFor all three patient cases, HUC treatment plans demonstrated comparable dosimetric quality to clinical plans, with similar PTV coverage (V95% within 0.5 %), homogeneity, and critical OAR-sparing. At the same time, HUC plans delivered a substantial portion of the dose to the PTV (Dmedian of 50–69 %) and surrounding tissues at UHDR. For the HUC boost treatment of the glioblastoma, the first FLASH sparing scenario showed a moderate FLASH sparing magnitude (10 % for D2%,PTV) for the 15-Gy UHDR electron boost, while the second scenario indicated a more substantial sparing of brain tissues inside and outside the PTV (32 % for D2%,PTV, 31 % for D2%,Brain). ConclusionsFrom a planning perspective, HUC treatments represent a feasible approach for delivering dosimetrically conformal UHDR treatments, potentially mitigating technical challenges associated with delivering conformal FLASH-RT for deep-seated tumours. While further research is needed to optimize HUC fractionation and delivery schemes for specific patient cohorts, HUC treatments offer a promising avenue for the clinical transfer of FLASH-RT.

Radiation shielding transmission data for modern digital radiography.

Radiography is one of the most widely used x-ray imaging modalities. In National Council on Radiation Protection and Measurements (NCRP) Report No. 147, transmission data for radiographic systems were evaluated on those installed before 2000. For x-ray systems (except intraoral dental) manufactured on or after June 10, 2006, the U.S. required minimum half-value layer (HVL) was increased; for example, 2.9 (2.3) mm Al at 80kV, where the value in parenthesis denotes the earlier requirement before the above date. To calculate the transmission of the broad x-ray beam of modern digital radiography (DR) through shielding materials. X-ray beam HVLs on two DR systems (Agfa DR 600, GE Revolution XR/d) were measured in 10kV increments between 60 and 120kV, with a calibrated ionization chamber (Radcal model 10×5-60) and varying thickness of aluminum 1100 plates. Monte Carlo (Geant4) simulation was performed to calculate the transmission of broad x-ray beams through lead, concrete, gypsum, and steel, with x-ray HVLs matching those of the DR 600 at two beam filtrations (default, 1mm Al plus 0.1mm Cu added filtration). The transmission data were fitted to the Archer equation. HVLs on two DR systems with default beam filtration were consistent (median difference, 2.1%; maximum difference, 5.5%). An additional beam filtration option (1mm Al plus 0.1mm Cu) on the DR 600 substantially increased HVLs by 45.2%-61.2%. Transmission fitting parameters were provided for seven tube voltages (60-120kV) at two beam filtrations. This work presents transmission data for modern DR systems, indicating increased x-ray beam filtration compared to the primary x-ray beam in NCRP Report No. 147. The updated transmission data can enhance structural shielding evaluations at individual tube voltages or with a workload distribution.

Deep-learning-based speech enhancement under rough-focus conditions with optical laser microphone

Optical laser microphones have attracted attention for acoustic systems capable of recording the target speech from a distance. An optical laser microphone measures the speech-induced vibration by focusing the laser beam on the surface of the vibrating object. A recording method called rough-focus recording using an unfocused laser beam, enables wide-range recording and robust recording against changes in focal length. However, with rough-focus recording, the broad laser beam coverage leads to insufficient intensity of the reflected laser for accurate acoustical signal measurement, resulting in speech-quality degradation, such as the inclusion of noise, and attenuation of high-frequency components in the acquired speech. To solve this problem, deep-learning-based speech-enhancement methods for optical laser microphones have been proposed. Such methods require separate models for different focus settings, exhibiting a lack of adaptability to changing focus settings. We propose a speech-enhancement method for training a single model for various focus settings. This model is trained with speech signals recorded across different focus settings to enhance speech recorded in various focus settings. Experimental results indicate that the this model trained with the proposed method performs equivalent to or better than a model trained with the conventional models.

Emergence of Amphiphilicity on Surfaces of Pure Cellulose Nanofibrils Directly Generated by Aqueous Counter Collision Process.

The present paper describes a downsizing mechanism of an aqueous counter collision (ACC) process that enables the rapid preparation of cellulose nanofibrils (CNFs) as an aqueous dispersion solely by impinging a pair of water jets containing the raw materials. Extensive studies have revealed that the resulting CNFs by ACC have amphiphilic fiber surfaces, in which two kinds of faces with different natures are present along the entire fiber axis. They therefore have superior adsorption to surfaces of various conventional polymer plastics. These characteristic adsorption behaviors, which are totally different from those for other CNFs prepared by other means, are attributable to their hydrophobic surfaces. In the present study, high-resolution microscopy, including atomic force microscopy, confocal laser scanning microscopy, and scanning electron microscopy with broad argon ion beam milling, was used to determine how the emergence of such hydrophobic characteristics in a nanofibril face occurs in relation to the ACC nanopulverization mechanism due to the collision of the pair of water jets.

A broad-beam reflective metasurface enhancing signal coverage for indoor wireless communication

ABSTRACT A broad-beam planar reflective metasurface design for indoor signal coverage is presented in this letter. The proposed metasurface unit is designed as a multi-resonant structure using an additional branch on the double ring, which achieves a reflection phase shift covering 360° and a reflection magnitude remaining above 0.8 by varying the length of the square ring. To simplify the array configuration, the unit incorporates 2-bit phase quantization. In order to broaden the reflection beam of metasurface, the phase distribution of the array is determined by the aperture field superposition method. The angles of the different electromagnetic (EM) waves within the single aperture are adjusted to be moderately distinct. The co-simulation and measurement of the horn antenna and the reflective metasurface are carried out. The results show that the metasurface can generate a broad beam at 4.8 GHz with a 3 dB beamwidth of 21°, achieving a beam gain of 18dBi. The broad beam can maintain a 3 dB beamwidth greater than 19° in the 4.2–5.6 GHz band. The reflective metasurface can be used as a passive repeater to optimize signal quality and enhance wireless communication coverage in indoor non-line-of-sight (NLOS) paths.