High Radiation Efficiency Research Articles

Design and Fabrication of a C-Band Patch Antenna with Low Loss BaM4Si5O17 Microwave Dielectric Ceramics.

Single-phase BaM4Si5O17 (M = Yb, Er, Y, Ho) ceramics have been investigated for their crystal structures, microwave dielectric properties, flexural strength, and potential applications in dielectric antennas. Rietveld refinement and TEM analysis revealed that the BaM4Si5O17 ceramics exhibit a monoclinic structure (space groups: P21/m). The εr of the BaM4Si5O17 ceramics was dominated by ionic polarizability and ρrel. The Q × f values were considerably larger at BaM4Si5O17 (M = Yb and Y) ceramics with the high Utotal and low intrinsic dielectric loss. The τf values were controlled by the MO6 octahedron distortion and -VBa. The flexural strength was mainly dominated by pores and average grain size and reached the maximum value (156 MPa) at BaY4Si5O17 ceramic with small average gain sizes and high relative density. Additionally, a patch antenna was fabricated using high-performance BaY4Si5O17 ceramic characterized by a εr value of 9.02, a Q × f value of 60620 at 12.30 GHz, and a τf value of -37.65 ppm/°C. This design achieved a high simulated radiation efficiency of 82.70% and a gain of 5.60 dBi at 6.97 GHz. indicating potential applications of BaY4Si5O17 ceramic because of its low dielectric loss and high flexural strength.

High radiation efficiency and tunable resonance planar double-turn spiral antenna for manipulation of nitrogen-vacancy centers.

Nitrogen-vacancy (NV) centers in diamond are promising quantum sensors, where microwave antennas play a crucial role in manipulating the spin states accurately. Conventional microwave antennas often struggle to balance radiation efficiency and bandwidth. To address this challenge, we design a planar double-turn spiral antenna (PDTSA), based on the ring microstrip antenna (RMA). PDTSA demonstrates an ∼4.5-fold increase in radiation efficiency compared to RMA. In addition, the PDTSA allows linear tunability of the resonance frequency up to 500MHz by adjusting the spiral input length. This feature addresses the limitations of a narrow working frequency range, which are typically caused by the narrowband in high-radiation-efficiency antennas. The experimental results show that at an absolute input power of 1W, the PDTSA increases the Rabi frequency from 1.72 to 8.06MHz compared to the RMA. This enhancement accelerates quantum state manipulation and reduces phase accumulation errors. These characteristics make PDTSA suitable for applications in quantum sensing and precision measurements using NV centers.

Realizing Orthogonal Modes in Compact Cavity‐Backed Dual‐Polarized Antenna Through Simple Feeding Structures for Millimeter‐Wave AiP Applications

AbstractThis paper presents a dual‐polarized cavity‐backed antenna designed for mm‐wave applications, featuring simple feeding structures with a high‐isolation for 60 GHz compact AiP applications. The dual‐polarization design relies on two separate feed ports that excite two orthogonal modes within the same resonant cavity, achieving very high port isolation of up to 40 dB over the entire band. We conducted a detail analysis of the antenna, including its working principles and parametric studies. For verification, we fabricated an antenna test kit using standard printed process on substrates and measured the kit from the back‐side of a GSG probing platform. The proposed antenna demonstrates a wide impedance bandwidth, stable radiation patterns, very low cross‐polarization levels, and a high radiation efficiency. The co‐located cavity‐backed design ensures the compactness and facilitates easy integration with ICs in a very small AiP module. These features make the proposed antenna highly suitable for 60 GHz AiP applications, such as high‐data‐rate wireless communication and mmW polarimetric radar systems.

Late Jets, Early Sparks: Illuminating the Premaximum Bumps in Superluminous Supernovae

Superluminous supernovae (SLSNe) radiate ≳10–100 times more energy than ordinary stellar explosions, implicating a novel power source behind these enigmatic events. One frequently discussed source, particularly for hydrogen-poor (Type I) SLSNe, is a central engine such as a millisecond magnetar or accreting black hole. Both black hole and magnetar engines are expected to channel a fraction of their luminosity into a collimated relativistic jet. Using 3D relativistic hydrodynamical simulations, we explore the interaction of a relativistic jet, endowed with a luminosity L j ≈ 1045.5 erg s−1 and duration t eng ≈ 10 days compatible with those needed to power SLSNe, launched into the envelope of the exploding star. The jet successfully breaks through the expanding ejecta, and its shocked cocoon powers ultraviolet/optical emission lasting several days after the explosion and reaching a peak luminosity ≳1044 erg s−1, corresponding to a sizable fraction of L j . This high radiative efficiency is the result of the modest adiabatic losses the cocoon experiences owing to the low optical depths of the enlarged ejecta at these late times, e.g., compared to the more compact stars in gamma-ray bursts. The luminosity and temperature of the cocoon emission match those of the “bumps” in SLSN light curves observed weeks prior to the optical maximum in many SLSNe. Confirmation of jet breakout signatures by future observations (e.g., days-long to weeks-long internal X-ray emission from the jet for on-axis observers, spectroscopy confirming large photosphere velocities v/c ≳ 0.1, or detection of a radio afterglow) would offer strong evidence for central engines powering SLSNe.

A High Gain Circularly Polarized Slot Antenna Array for 5G Millimeter-Wave Applications

An air-filled substrate-integrated waveguide (AF-SIW) circularly polarized (CP) 1 × 8 mm wave antenna array is presented for fifth-generation (5G) applications. The presented slot antenna array consists of three layers of PCB and one layer of aluminum, which serve as the AF-SIW feeding network and the metal cavity radiation element, respectively. The CP characteristic is achieved by the use of an S-shaped aluminum radiation cavity on the top of the AF-SIW feeding network. The air-filled substrate-integrated waveguide technique is unitized to achieve high radiation efficiency. A wide input impedance bandwidth of 18.4% is obtained for the proposed antenna scheme, ranging from 34.5 GHz to 41.5 GHz, with a peak gain of 18 dBic. As for CP characteristic, the proposed antenna possesses a wide 3 dB axial ratio (AR) bandwidth, which is 16.4% (36.5 GHz to 43 GHz). The antenna scheme is fabricated and measured to verify the potential application as well as the promising performance. The measured results of the 1 × 8 antenna array shows that the wide AR as well as the input impedance are simultaneously achieved, which coincide well with the simulated results. Also, the measured results indicate that the proposed antenna scheme might be a good candidate for future mobile applications.

Simulation study of multi-layer titanium nitride nanodisk broadband solar absorber and thermal emitter

Solar energy has always been a kind of energy with large reserves and wide application. It is well utilized through solar absorbers. In our study, the finite difference time domain method (FDTD) is used to simulate the absorber composed of refractory metal materials, and its absorption performance and thermal emission performance are obtained. The ultra-wide band of 200 nm–3000 nm reaches 95.93% absorption efficiency, of which the bandwidth absorption efficiency of 2533 nm (200 nm–2733 nm) is greater than 90%. The absorption efficiency in the whole spectrum range (200 nm–2733 nm) is 97.17% on average. The multilayer nanodisk structure of the absorber allows it to undergo strong surface plasmon resonance and near-field coupling when irradiated by incident light. The thermal emission performance of the absorber enables it to also be applied to the thermal emitter. The thermal emission efficiency of 95.37% can be achieved at a high temperature of up to 1500 K. Moreover, the changes of polarization and incident angle do not cause significant changes in absorption. Under the gradual change of polarization angle (0°–90°), the absorption spectrum maintains a high degree of consistency. As the incident angle increases from 0° to 60°, there is still 85% absorption efficiency. The high absorption efficiency and excellent thermal radiation intensity of ultra-wideband enable it to be deeply used in energy absorption and conversion applications.

H-Shape Microstrip Patch Antenna: Design, Simulation, and Characterization

This paper presents the design, simulation, and characterization of an H-shape microstrip patch antenna intended for high-frequency applications. The proposed antenna is modeled using Computer Simulation Technology (CST) Microwave Studio, a powerful tool for simulating electromagnetic fields and optimizing antenna parameters. The H-shaped configuration is chosen to enhance the antenna's radiation characteristics, bandwidth, and gain, while minimizing size and surface wave effects. The design process involves parameter optimization, including substrate selection, patch dimensions, and feed point configuration, to achieve superior performance. Detailed simulation results are presented, demonstrating the antenna's return loss, VSWR, gain, and radiation pattern. The antenna operates efficiently with stable resonance, offering low return loss and high radiation efficiency. The simulation results confirm that the H-shape microstrip patch antenna is well-suited for various wireless communication systems, showing potential for integration in compact, high-performance devices. This paper serves as a step towards further optimization and practical implementation of H-shape microstrip antennas in advanced RF systems.

GRB 190114C: Fireball Energy Budget and Radiative Efficiency Revisited

The jet composition of gamma-ray bursts (GRBs), as well as how efficiently the jet converts its energy to radiation, are long-standing problems in GRB physics. Here, we reported a comprehensive temporal and spectral analysis of the TeV-emitting bright GRB 190114C. Its high fluence (∼4.4 × 10−4 erg cm−2) allows us to conduct the time-resolved spectral analysis in great detail and study their variations down to a very short timescale (∼0.1 s) while preserving a high significance. Its prompt emission consists of three well-separated pulses. The first two main pulses (P 1 and P 2) exhibit independently strong thermal components, starting from the third pulse (P 3) and extending to the entire afterglow, the spectra are all nonthermal, and the synchrotron plus Compton upscattering model well interprets the observation. By combining the thermal (P 1 and P 2) and the nonthermal (P 3) observations based on two different scenarios (global and pulse properties) and following the method described in Zhang et al., we measure the fireball parameters and GRB radiative efficiency with little uncertainties for this GRB. A relevantly high GRB radiative efficiency is obtained based on both the global and pulse properties, suggesting that if GRBs are powered by fireballs, the efficiency can sometimes be high. More interestingly, though the observed parameters are individually different (e.g., the amount of mass loading M), the radiative efficiency obtained from P 1 (η γ = 36.0% ± 6.5%) and P 2 (η γ = 41.1% ± 1.9%) is roughly the same, which implies that the central engine of the same GRB has some common properties.

Open-slit circular tube piezoelectric ultrasonic transducer with longitudinal bending mode conversion

Abstract A new type of longitudinal bending mode conversion ultrasonic transducer is designed by compounding a sandwich type piezoelectric ultrasonic transducer, amplitude transformer and Open-slit circular tube radiator. The radiator is made of a circular tube cut into a number of curved plates along the axis, and the two ends are thin disc end caps. The electromechanical equivalent circuit model of the transducer is established and its frequency equation is derived. The vibration performance of the transducer is studied by using the equivalent circuit method and the finite element method. The results show that: the new structure design and the longitudinal vibration sandwich piezoelectric ultrasonic transducer can effectively stimulate the two ends of the slit circular tube radiator to produce first-order bending vibration, and the curved plate to produce high-order bending vibration, so as to achieve high efficiency, uniform and all-round ultrasonic radiation. The research results are expected to be applied in ultrasonic treatment of large volume liquid such as ultrasonic wastewater treatment, ultrasonic algae removal and ultrasonic chemical reaction.

High efficiency and circular polarization in SATCOM phased arrays using tri-ridge apertures

A new antenna array architecture is proposed here to overcome a current bottleneck in phased arrays concerning the enhancement of radiation efficiency and avoidance of scan blindness. In contrast to the conventional approach of using patches with circular or square geometries that exploit 90∘\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$^\\circ$$\\end{document} or 180∘\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$^\\circ$$\\end{document} rotational symmetry, this work proposes to use waveguide radiating elements based on 120∘\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$^\\circ$$\\end{document} symmetry. To implement such symmetry, the tri-ridge aperture is proposed, and its capability to scan widely within a broad frequency bandwidth is demonstrated. A modal analysis is performed to explain the physical phenomena underlying such superior performance. A successful experimental validation is provided by means of a monolithic prototype built in metal additive manufacturing. The measured results show, for the first time, that it is possible to achieve high radiation efficiency and circular polarization when scanning widely in a broad bandwidth. Such an accomplishment constitutes a major achievement in the field of active electronically steered phased arrays, and impacts significantly the capabilities and potential of modern radar and communication systems.

Experimental demonstration of a silicon nanophotonic antenna for far-field broadened optical phased arrays

Optical antennas play a pivotal role in interfacing integrated photonic circuits with free-space systems. Designing antennas for optical phased arrays ideally requires achieving compact antenna apertures, wide radiation angles, and high radiation efficiency all at once, which presents a significant challenge. Here, we experimentally demonstrate a novel ultra-compact silicon grating antenna, utilizing subwavelength grating nanostructures arranged in a transversally interleaved topology to control the antenna radiation pattern. Through near-field phase engineering, we increase the antenna’s far-field beam width beyond the Fraunhofer limit for a given aperture size. The antenna incorporates a single-etch grating and a Bragg reflector implemented on a 300-nm-thick silicon-on-insulator (SOI) platform. Experimental characterizations demonstrate a beam width of 44°×52° with −3.22 dB diffraction efficiency, for an aperture size of 3.4 μm×1.78 μm. Furthermore, to the best of our knowledge, a novel topology of a 2D antenna array is demonstrated for the first time, leveraging evanescently coupled architecture to yield a very compact antenna array. We validated the functionality of our antenna design through its integration into this new 2D array topology. Specifically, we demonstrate a small proof-of-concept two-dimensional optical phased array with 2×4 elements and a wide beam steering range of 19.3º × 39.7º. A path towards scalability and larger-scale integration is also demonstrated on the antenna array of 8×20 elements with a transverse beam steering of 31.4º.

Acoustic properties and attenuation of coupled shaft-submarine hull system under various excitation transfer paths

Pump-jet propulsor excitation transfers to submarine hull along rotor-shaft and duct-stator paths simultaneously. The investigations on the effects of excitation transfer paths on structural vibration and acoustic radiation of submarine are limited. The present work aims to investigate vibro-acoustic characteristics of coupled shaft-submarine hull system utilizing a theoretical wavenumber analysis method and conduct acoustic design. The energy functional of the coupled structure-fluid system of the research object is first developed, and the displacement components of the jointed shell and the acoustic pressure are expanded by the Fourier series along circumferential direction. This allows for obtaining vibro-acoustic responses in the circumferential wavenumber-frequency domain, by which the predominant wavenumbers contributing to acoustic radiation are identified. The discussions reveal that the modes n = 0 and n = 1 respectively dominate the acoustic radiation under axial and vertical rotor loads. The acoustic radiations under duct-stator load are mainly contributed by mode n = 0, and the higher order modes n = 1 and n = 2 determine several acoustic peaks. Furthermore, two acoustic design schemes are proposed to suppress the wavenumbers with high radiation efficiency. It is proven that the design of the symmetric inner foundation and the application of new material are two efficient ways to improve acoustic performance of the submarine.

Sound transmission of truss-based X-shaped inertial amplification metamaterial double panels

To enhance the low-frequency sound insulation performance of conventional double panels, this work proposes a truss-based X-shape inertial amplification (TXIA) metamaterial double panel. A semi-analytical method is developed for computing the sound transmission loss (STL) of the TXIA metamaterial double panel, with numerical and experimental validations confirming the convergence and accuracy of this method. To further investigate the low-frequency acoustic wave attenuation of the proposed structure, four configurations are analyzed and discussed. Numerical results indicate that, compared to conventional and equivalent mass double panels, the TXIA metamaterial double panel effectively shifts the STL peaks to lower frequencies, exhibiting higher STL amplitudes and a reduced low-STL region. Configurations incorporating different springs enhance the STL performance without altering mass or other parameters. The STL dips of the metamaterial double panel coincide with odd-odd modes of the double panel, which have higher radiation efficiencies. Parametric studies reveal that changes in the IA angle shift the dips induced by in-phase modes to lower frequencies, while increased stiffness shifts these in-phase dips to higher frequencies. The depth of the cavity between the two panels only affects the first-order anti-phase dip. Additionally, increased stiffness enhances the STL performance and introduces a new peak in the stiffness-controlled region. Due to its flexibility, the TXIA metamaterial double panel holds significant potential for industrial applications.

Asymmetric Structural Engineering of Hot-Exciton Emitters Achieving a Breakthrough in Non-Doped BT.2020 Blue OLEDs with a Record 9.5% External Quantum Efficiency.

High-efficiency non-doped deep-blue organic light-emitting diodes (OLEDs) meeting the standard of BT.2020 color gamut is desired but rarely reported. Herein, an asymmetric structural engineering based on crossed long-short axis (CLSA) strategy is developed to obtain three new deep-blue emitters (BICZ, PHDPYCZ, and PHPYCZ) with a hot-exciton characteristic. Compared to 2BuCz-CNCz featuring a symmetric single hole-transport framework, these asymmetric emitters with the introduction of different electron-transport units show the enhancement of photoluminescence efficiency and improvement of bipolar charge transport capacity. Further combined with high radiative exciton utilization efficiency and light outcoupling efficiency, the non-doped OLED based on PHPYCZ exhibits the best performance with an excellent current efficiency of 3.49%, a record-high maximum external quantum efficiency of 9.5%, and a CIE y coordinate of 0.049 approaching the BT.2020 blue point. The breakthrough obtained in this work can inspire the molecular design of deep-blue emitters for high-performance non-doped BT.2020 blue OLEDs.

A Wideband Millimeter-Wave Dual-Beam Dielectric Resonator Antenna with Substrate Integration Capability.

A wideband dual-beam dielectric resonator antenna (DRA) with substrate integration capability was proposed for millimeter-wave (mm-wave) applications. The four rows of air vias along the x-direction and two extended rectangular patches could shift the undesirable radiation mode upward and move the conical-beam radiation mode downward, respectively. Thus, the TE211 mode and the TE411 mode of the patch-loaded perforated rectangular substrate integrated dielectric resonator (SIDR) supporting the dual-beam radiation can be retained in the operating band, and their radiation can be improved by the air vias along the y-direction. The T-shaped line coupled dual-slot structure could excite the above two modes, and a dual-slot mode supporting dual-beam radiation could also work. Then, a wideband DRA with a stable dual-beam radiation angle can be achieved, and its impedance matching can be improved by two air slots on two sides. Compared with the state-of-the-art dual-beam antennas, the proposed antenna shows a wider bandwidth, a higher radiation efficiency, and the substrate integration capability of DRA, making it more suitable for mm-wave applications. For demonstration, a 1 × 4 array was designed with the 10 dB impedance matching bandwidth of 41.2% and the directions of the dual beams between ±30° and ±35°.

A Scalable 32–38-GHz Transmitter and Receiver Phased Array With High Radiation Efficiency in UV-LIGA-Based Ceramic Packaging

A Scalable 32–38-GHz Transmitter and Receiver Phased Array With High Radiation Efficiency in UV-LIGA-Based Ceramic Packaging

Efficacy of Tilt-Angle and Low-Dose CT Scan Guidance in Percutaneous plasma Radiofrequency Treatment for Lumbar 5-Sacrum 1 Disc Herniation.

To investigate the application effect of tilt-angle low-dose ComputedTomography (CT) scanning guidance technology in the plasma radiofrequency treatment of lumbar 5-sacrum 1 (L5-S1) intervertebral disc herniation. A total of 43 patients with L5-S1 disc herniation were included in this study and categorized into vertical-angle-guided CT (Group A, n = 21) and tilt-angle-guided CT (Group B, n = 22) groups. Percutaneous plasma L5-S1 disc radiofrequency treatment was administered. The total number of punctures and scans, operation times, and Numerical Rating Scale (NRS) pain scores (preprocedure and 3 and 30 days postprocedure) were documented. Compared with Group A, punctures and scans were fewer in Group B, and the differences were statistically significant (P = 0.0001). Moreover, the CT scan-guided total surgery time was significantly shorter in Group B than in Group A (P = 0.0001). In addition, the NRS score exhibited a statistically significant difference among preprocedure (T0), 3 day postprocedure (T1), and 30 days (T2) in Groups A (P < 0.05). The NRS score exhibited a statistically significant difference between T0 and T1 and between T0 and T2 in Group B (P < 0.05), but not between T1 and T2 in Group B (P = 0.084). At three time points (T0, T1, T2), there was no statistically significant difference between the two groups (P > 0.05). The tilt-angle low-dose CT scanning technique for L5-S1 disc herniation offers the advantages of high efficiency, low damage, and low radiation, and its clinical application is recommended.

RESEARCH TREND ON IMPROVEMENT OF DIELECTRIC RESONATOR ANTENNA: A BIBLIOMETRIC ANALYSIS

Dielectric Resonator Antennas (DRAs) have components in modern wireless communication systems due to their compact size, high radiation efficiency, and frequency versatility. With escalating demands for higher data rates and spectrum efficiency, the enhancement of DRAs has garnered significant attention in antenna research. Despite the promising characteristics of DRAs, there exists a gap in providing a consolidated overview of the state-of-the-art advancements and emerging themes in DRA research. This study aims to bridge this gap by conducting a meticulous bibliometric analysis to delineate the research trends, highlight gaps, and guide future investigations. Our methodology involves a systematic search and analysis of scholarly publications related to the improvement of DRAs. We use bibliometric tools, citation analysis, and co-authorship networks to explore publication trends, influential authors, and collaborative networks within the DRA research community. By identifying emerging themes, key contributors, and collaborative networks, this study is poised to inform researchers, practitioners, and policymakers about the prevailing trends in the field. The insights gained are expected to guide future research directions, foster interdisciplinary collaboration, and contribute to the continued evolution of DRAs. In conclusion, this bibliometric analysis aims to provide a roadmap for navigating the intricate research landscape on the improvement of DRAs. The anticipated outcomes hold the potential to drive innovation, inspire collaborative initiatives, and contribute to the ongoing advancement of DRAs in the rapidly evolving realm of wireless communication systems.

Design of Miniaturized and Wideband Four-Port MIMO Antenna Pair for WiFi.

A miniaturized and wideband four-port multiple-input multiple-output (MIMO) antenna pair for Wi-Fi mobile terminals application is proposed. The proposed antenna pair consists of four multi-branch antenna elements arranged orthogonally, with an overall size of 40 × 40 × 3.5 mm3 and each antenna element size of 15.2 × 3.5 mm × 0.8 mm3. The performance of the proposed antenna shows the advantages of a wide frequency band, low mutual coupling, high efficiency, and a compact structure. The wideband characteristics of the antenna elements are achieved through multi-mode resonance. The suppression of coupling is accomplished by strategically positioning the four compact antenna elements to ensure their maximum radiation directions are orthogonal, thus eliminating the need for an additional decoupling structure. In this paper, the proposed antenna is optimized in terms of the parameters then simulated and measured. The simulated results illustrate that an impedance bandwidth of the antenna is about 15% (5.06~5.88 GHz) with S11 < -10 dB, excellent port isolation exceeds 20 dB between all ports, a high radiation efficiency ranges from 51.2% to 89.9%, the maximum gain is 4.5 dBi, and the ECCs are less than 0.04. The measured results show that the -10 dB impedance bandwidth of the antenna is about 13% (5.13~5.80 GHz), the isolation between the antenna elements is better than 21 dB, the radiation efficiency ranges from 51.8% to 92.3%, the maximum gain is 5.3 dBi, and the ECCs are less than 0.05. The proposed four-port MIMO antenna works on the 5G LTE band 46 and Wi-Fi 6E operating bands. As a mobile terminal antenna, the proposed design scheme demonstrates excellent performance and applicability, fulfilling the requirements for 5G mobile terminal applications.

Eco-Friendly packaging film with integrated functions of High-Efficiency radiation cooling and Sustained-Release antimicrobial activity

The storage temperature and microbial contamination typically have significant impact on the deterioration rate and postharvest lifespan of fresh food. To meet the critical requirements of fresh food packaging, a hybrid functional packaging coating is developed by combing tannic acid (TA) as a binder, chitin nanofibers (CNF) as a crosslinker, and acidified halloysite nanotubes containing Apigenin (CA@e-HNTs) as an antimicrobial/cooling agent. The functional coating was sprayed on a poly(butylene adipate-co-terephthalate) (PBAT) substrate, integrating both radiative cooling capabilities and sustained antimicrobial properties. The hybrid film achieved subambient cooling through a high solar reflectance (90.5 %) and high mid-infrared emittance (94.0 %), resulting in a temperature of 6.2 ℃ below ambient under intense sunlight. When used for fresh food packaging, the hybrid functional film outperformed other commercially available food packaging materials in maintaining the quality of Agaricus bisporus and extending the storage time of fresh strawberries to 9 days. Moreover, the film exhibited excellent antibacterial and antioxidant properties. This zero-energy cooling technology with sustained antimicrobial characteristics has enormous potential for application in the preservation of fresh food, offering a more sustainable way to extend the shelf life of fresh produce and reduce food waste.