Feed Line Research Articles

Design and analysis of planar four-port UWB-MIMO antenna with band-rejection capability

Abstract This manuscript presents a 50 Ω microstrip-fed quad-element high isolated ultra-wideband (UWB) multiple-input multiple-output (MIMO) antenna with band-notched characteristics. The overall area of the proposed structure is 0.33λo × 0.33λo mm2 (where λo depicts the free space wavelength corresponding to the lower cutoff frequency, i.e. 2.54 GHz), etched on an FR-4 substrate of thickness 0.8 mm. The top layer has four semicircular disc-shaped radiating elements that are identical and orthogonal to obtain better inter-element isolation and compactness. A reverse two-shaped slot is etched onto the radiating patches to attain a band-rejection capability. Moreover, a decoupling structure is also placed at the top layer to suppress the unwanted surface waves. The bottom layer consists of a ground plane, which is further modified with quasi-self complementary and meandered line slots. A rectangular slot is also etched below the feed line to better match the impedance near the lower cutoff frequencies. The simulated reflection coefficients (S11) of the proposed antenna are less than −10 dB over 2.54 to 10.74 GHz frequencies except at 3.37 to 4.15 GHz (WiMAX/C band), and the simulated inter-port isolation (S21) is greater than −15 dB over the entire UWB range of frequencies (3.1 to 10.6 GHz). Also, the measured S-parameter results well agreed with the simulated ones. Furthermore, the simulation study of the 20-element UWB-MIMO antenna is also investigated using the proposed quad-element structure.

Development of productive pseudocapsulated compound feeds for rainbow trout grown in the Central Federal District of the Russian Federation

The decrease in catch of valuable fish species from natural water bodies is compensated by their intensive cultivation in artificial conditions. In order to realize the main task of trout farms associated with obtaining marketable products in the shortest possible period of time, artificial feed is used as a source of food. A economically feasible alternative source of raw materials is the products of plant origin. In the process of production of oil and fat products at various stages, numerous fat wastes and by-products are formed, wich have fodder value and are not used as feeding facilities in industrial scale. This is especially frue for fat processing (soapstock of Light oil, fatty bleaching clays, dezodoration chases, phosphatides, calcium salts of fatty acids), as well as waste oils in combination with fat processing waste. On the base of studying the classical technology of producing mixed fodders for valuable fish species and eliminating its drawbacks the technology of pseudocapsulated mixed fodders for salmon fish grown in the CFD of Russia Federation with given fodder value and a line for its realization is suggested. The best way to bring fats and vitamins contained in them to valuable fish species is to feed them as a part of mixed fodders. At present, however, it is difficult to increase the level of fat in feed on the existing Russian fats supply lines, since most plants can include up to 10% of fat in the bulk feed line. Therefore, the development of mixing formulations and techniques for valuable fish breeds using sturgeon fish with more than 10% fat in it as an addition of fat oily wastes such as epaulettes and phosphates is not only of scientific interest. In the course of studies optimization encapsulated optimal feeds for program "Feed Optima Expert" pseudorainbow trout were also developed. As a result, close results were obtained in terms of the rate of growth of trout, the development, conversion of feed and viability in comparison with the best feed counterparts on the Russian market.

Notch-band eliminator wideband CSRR loaded monopole fractal antenna for ISM and PCS communications

PurposeThis paper aims to present a low-cost, edge-fed, windmill-shaped, notch-band eliminator, circular monopole antenna which is practically loaded with a complementary split ring resonator (CSRR) in the middle of the radiating conductor and also uses a partial ground to obtain wide-band performance.Design/methodology/approachTo compensate for the reduced value of gain and reflection coefficient because of the full (complete) ground plane at the bottom of the substrate, the antenna is further loaded with a partial ground and a CSRR. The reduction in the length of ground near the feed line improves the impedance bandwidth, and introduced CSRR results in improved gain with an additional resonance spike. This results in a peak gain 3.895dBi at the designed frequency 2.45 GHz. The extending of three arms in the circular patch not only led to an increase of peak gain by 4.044dBi but also eliminated the notch band and improved the fractional bandwidth 1.65–2.92 GHz.FindingsThe work reports a –10dB bandwidth from 1.63 GHz to 2.91 GHz, which covers traditional coverage applications and new specific uses applications such as narrow LTE bands for future internet of things (NB-IoT) machine-to-machine communications 1.8/1.9/2.1/2.3/2.5/2.6 GHz, industry, automation and business-critical cases (2.1/2.3/2.6 GHz), industrial, society and medical applications such as Wi-MAX (3.5 GHz), Wi-Fi3 (2.45 GHz), GSM (1.9 GHz), public safety band, Bluetooth (2.40–2.485 GHz), Zigbee (2.40–2.48Ghz), industrial scientific medical (ISM) band (2.4–2.5 GHz), WCDMA (1.9, 2.1 GHz), 3 G (2.1 GHz), 4 G LTE (2.1–2.5 GHz) and other personal communication services applications. The estimated RLC electrical equivalent circuit is also presented at the end.Practical implicationsBecause of full coverage of Bluetooth, Zigbee, WiFi3 and ISM band, the proposed fabricated antenna is suitable for low power, low data rate and wireless/wired short-range IoT-enabled medical applications.Originality/valueThe antenna is fabricated on a piece (66.4 mm × 66.4 mm × 1.6 mm) of low-cost low profile FR-4 epoxy substrate (0.54 λg × 0.54 λg) with a dielectric constant of 4.4, a loss tangent of 0.02 and a thickness of 1.6 mm. The antenna reflection coefficient, impedance and VSWR are tested on the Keysight technology (N9917A) vector network analyzer, and the radiation pattern is measured in an anechoic chamber.

Dual-Band Dielectric Resonator Antenna with Filtering Features for Microwave and Mm-Wave Applications.

This paper presents a new design for a dual-band double-cylinder dielectric resonator antenna (CDRA) capable of efficient operation in microwave and mm-wave frequencies for 5G applications. The novelty of this design lies in the antenna's capability to suppress harmonics and higher-order modes, resulting in a significant improvement in antenna performance. Additionally, both resonators are made of dielectric materials with different relative permittivities. The design procedure involves the utilization of a larger cylinder-shaped dielectric resonator (D1), which is fed by a vertically mounted copper microstrip securely attached to its outer surface. An air gap is created at the bottom of (D1), and a smaller CDRA (D2) is inserted inside this gap, with its exit facilitated by a coupling aperture slot etched on the ground plane. Furthermore, a low-pass filter (LPF) is added to the feeding line of D1 to eliminate undesirable harmonics in the mm-wave band. The larger CDRA (D1) with a relative permittivity of 6 resonates at 2.4 GHz, achieving a realized gain of 6.7 dBi. On the other hand, the smaller CDRA (D2) with a relative permittivity of 12 resonates at a frequency of 28 GHz, reaching a realized gain of 15.2 dBi. The dimensions of each dielectric resonator can be independently manipulated to control the two frequency bands. The antenna exhibits excellent isolation between its ports, with scattering parameters (S12) and (S21) falling below -72/-46 dBi at the microwave and mm-wave frequencies, respectively, and not exceeding -35 dBi for the entire frequency band. The experimental results of the proposed antenna's prototype closely align with the simulated results, validating the design's effectiveness. Overall, this antenna design is well-suited for 5G applications, offering the advantages of dual-band operation, harmonic suppression, frequency band versatility, and high isolation between ports.

Minaret Shape Micro-Strip Patch Antenna with Partial Ground Plane for Lower 5G and Wi-Max Applications

Antennas are a difficult component to design, yet they play critical functions in wireless transmission systems. To construct the required antenna, the antenna designer must overcome enormous challenges in getting all of the antenna's optimal qualities. Antenna designers must consider antenna factors like bandwidth, return loss, VSWR, gain, directivity, efficiency, and so on, for specific applications. So keep all parameter values as optimal as possible; sometimes you may need to adjust the design of the antenna from its standard shape. The present investigation describes the development of a partial ground-plane micro-strip patch antenna in the shape of a minaret for use in lower 5G and Wi-MAX networks. A microstrip patch antenna with a minaret-shaped radiating element and a partial ground plane is suggested. The suggested antenna is simple because it does not include any unwanted components on the patch, yet the significant gain is maintained by optimizing the ground plane's dimensions and position. The proposed antenna is constructed using a Rogers RT5880 (lossy) substrate, the line feeding method, and 0.035 mm thick (annealed) copper for the patch and ground components. CST Studio Suite 2018 is used for layout and modelling. The antenna is 28 x 16 x 0.79 mm3 and offers a maximum gain of 2.321 dB and a maximum directivity of 2.529 dBi. The recommended antenna has a frequency range of 3.3721 GHz to 4.2382 GHz, making it usable for both low-band 5G and Wi-MAX systems.

Dynamic cyclic kitting part-feeding scheduling for mixed-model assembly line by a hybrid quantum-behaved particle swarm optimization

PurposeThe purpose of this paper is to cut down energy consumption and eliminate production waste on mixed-model assembly lines. Therefore, a supermarket integrated dynamic cyclic kitting system with the application of electric vehicles (EVs) is introduced. The system resorts to just-in-time (JIT) and segmented sub-line assignment strategies, with the objectives of minimizing line-side inventory and energy consumption.Design/methodology/approachHybrid opposition-based learning and variable neighborhood search (HOVMQPSO), a multi-objective meta-heuristics algorithm based on quantum particle swarm optimization is proposed, which hybridizes opposition-based learning methodology as well as a variable neighborhood search mechanism. Such algorithm extends the search space and is capable of obtaining more high-quality solutions.FindingsComputational experiments demonstrated the outstanding performance of HOVQMPSO in solving the proposed part-feeding problem over the two benchmark algorithms non-dominated sorting genetic algorithm-II and quantum-behaved multi-objective particle swarm optimization. Additionally, using modified real-life assembly data, case studies are carried out, which imply HOVQMPSO of having good stability and great competitiveness in scheduling problems.Research limitations/implicationsThe feeding problem is based on static settings in a stable manufacturing system with determined material requirements, without considering the occurrence of uncertain incidents. Current study contributes to assembly line feeding with EV assignment and could be modified to allow cooperation between EVs.Originality/valueThe dynamic cyclic kitting problem with sub-line assignment applying EVs and supermarkets is solved by an innovative HOVMQPSO, providing both novel part-feeding strategy and effective intelligent algorithm for industrial engineering.

Chamfered edge filtering ultra-wideband antenna integrated with H-unit cell-loaded feed line for improved out-of-band rejection

Abstract This paper proposes a passive filtering antenna for ultra-wideband (UWB) applications. The edge chamfering technique is adopted to construct the UWB antenna. The designed UWB antenna has a fractional bandwidth of 135%. A low-pass filter (LPF) is embedded on the feed line of the UWB antenna to convert it into a narrowband antenna that works at 2.45 GHz with 29.5% fractional bandwidth by removing the high-frequency components. The LPF is a transmission line with a stepped impedance configuration loaded with an H-shaped unit cell. The proposed filtering antenna is fabricated and tested. The measured results indicate the gain is >4.2 dBi and the radiation efficiency is >75%.

3-D printed dual-band, dual-sense circularly polarized dielectric resonator antenna with a bandstop filtering response using planar via-free D-CRLH feeding network

A novel concept to design a dual-band, dual-sense circularly polarized (CP) antenna with a bandstop filtering response is presented by adopting an elaborate-designed irregular-shaped dielectric resonator (ISDR) and a dual-composite right/left-handed (D-CRLH)-based feeding network. First, the TEy111 and TEy113 modes of a rectangular DR (rDR) are simultaneously excited using an offset feeding slot, to realize the dual-band, linearly polarized (LP) operation in the x-direction. To eliminate the effects of the offset feeding on antenna performance, two types of edge-cuts and an impedance transformer are introduced. Secondly, another microstrip line and offset feeding slot are utilized to excite TEx111 and TEx113 modes of the DRA, obtaining dual-LP in two bands, and the corner truncation is introduced to reduce the cross-polarized field. Accordingly, a dual-band, dual-LP DRA with boresight radiation and low cross-polarization is achieved. After that, building on this design, a dual-band feeding network based on the D-CRLH resonator is employed to further implement the dual-sense CP operation. Finally, the ISDR is manufactured using 3-D printed technology for demonstration. The measured results show that the proposed antenna obtains a 3-dB axial ratio (AR) bandwidth of 9.3 % for the left-hand circular polarization (LHCP) at the lower band and 3.6 % for the right-hand circular polarization (RHCP) at the upper band. Moreover, the proposed antenna also features good suppression between two bands as the D-CRLH resonator offers a stopband filtering effect.

A Compact Dual-Polarized Endfire Antenna Array for 5G Millimeter-Wave Terminal

This paper proposes a compact dual-polarized end-fire antenna array for 5G millimeter-wave (mmWave) application. The dual-polarized antenna unit is constructed by an open-ended substrate integrated waveguide (SIW) cavity for vertically polarized (VP) radiation and a broadband electric dipole for horizontally polarized (HP) radiation. By sharing the side walls of two neighboring SIW channels of the VP elements, the substrate integrated coaxial line (SICL) feeding structure for the HP element is achieved, thus a compact size of the final antenna array can be accomplished. To extend the bandwidth of the VP element, the quasi-TE <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">11</sub> mode of the cavity and the slot mode of the end-fire aperture are adopted for the VP element. A corresponding linear array with four units is designed and fabricated. The common -10-dB impedance bandwidth covers from 24.8 GHz to 29.2 GHz. The maximum gain is 10.0 dBi for both polarizations, with an overlapped scanning coverage ranging from -41.5º to 45.5º at 27 GHz. The proposed design has a compact configuration, and a wide scanning range, which is alternative for 5G mmWave terminal application.

Design of slot loaded CPW feed ultra-wideband antenna with WLAN band notch characteristics

The fast development has been noticed during in the last few decades in the area of Ultra-wideband technologies. Throughout this manuscript, a novel ultra wideband (UWB) antenna with single band notched functions with CPW feed line is projected. The single band rejection is presented and analyzed at WLAN frequency. The proposed antenna was initially exhibits the voltage standing wave ratio (VSWR) bandwidth of 10.6 GHz with frequency range of 3.05 to 13.65 GHz. Further to achieve the WLAN band rejection at 5.5 GHz, an arc shaped slot has been presented in the geometry of radiating patch. The size of designed antenna is 27 × 27 mm2. It also shows that the VSWR ≤ 2 for the operating UWB frequency range, except stop band from 5.16 to 6.7 GHz for filtering the WLAN signal. A variety of UWB antenna applications can be found in medical and radar imaging as well as higher data rate Personal Area Networks (PANs). The designed antenna is simulated on the low cost FR4 glass epoxy substrate with dielectric constant 4.4 and thickness 1.6 mm. Performance parameters such as VSWR, radiation pattern and gain of proposed antenna are analyzed by using HFSS V13 simulator.

A Miniaturized Wearable Antenna With Five Band-Notched Characteristics for Medical Applications

In this paper, a miniaturized wearable antenna is proposed, which has five band-notched characteristics. The antenna uses Rogers 5880 as the dielectric substrate, with a thickness of 0.508mm. Due to its thickness, the antenna can be bent slightly and used in the wearable field. The antenna is fed by a microstrip line with an input impedance of 50 ohms. Through the design of notch structures inside the radiating patch, on either side of the feed line, and on the bottom of the substrate, five notch bands are made possible. More notch bands can be produced by employing a new structure which produces two notch bands as well as adding metal on the substrate's sides that allows current to be introduced into the notch structures on the bottom of the substrate. Based on this, it is possible to achieve great space utilization and little interaction amongst notch structures. The proposed antenna has overall size of 30x25x0.508mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> and covers the entire UWB spectrum from 2.56 GHz to 12.7 GHz except notch bands from 2.58 GHz to 3.21 GHz, 4.05 GHz to 4.29 GHz, 5 GHz to 5.64 GHz, 8.60 GHz to 9.05 GHz, 9.20 GHz to 10.32 GHz. By applying the antenna to the doctor's chest badge, the number of swiping cards by hands can be reduced, which is convenient and avoids bacterial pollution. Thus, the antenna has a useful purpose in the medical development.

Survival persistence of the 3 common Salmonella enterica serotypes isolated from broilers' in different matrices

Broiler meat is the predominant source of Salmonella as a foodborne pathogen. Several control strategies have focused on the reduction of Salmonella spp. levels at different production stages. However, the persistence of Salmonella between consecutive flocks is still of great concern. This study was designed to understand the cause of reinfection in broiler flocks due to survival of Salmonella in feeding lines of related matrices. Salmonella (S.) Enteritidis, S. Infantis, and S. Typhimurium isolated from broiler farms in North-West Germany were used. Four types of matrices (phosphate buffer saline (PBS), dietary plant fat, fat with feed mixture, and feed) were applied to evaluate Salmonella survival (with the initial dose about 8.0 log10 CFU/mL) during a simulation of 4 production cycles. To evaluate the growth and survival status of Salmonella ISO 6579-1:2017 were performed (quantitatively by plate count method (PCM) and most probable number method (MPN)) and qualitatively) at 5 defined time points (-7, 0, 4, 7, and 35 d). In all matrices and for the 3 serovars, the Salmonella count decreased at the end of the fourth cycle in comparison to the beginning of the experimental infection, and was still cultivated except for fat matrix. The PBS matrices showed the highest survival level of Salmonella and did not decline drastically by the end of the fourth cycle (5.93 ± 0.00, 5.87 ± 0.02, 5.73 ± 0.05 log10 CFU/mL, respectively). However, the fat matrices showed the lowest survival level for the 3 isolates at d 35 since the first cycle (0log10 CFU/mL using PCM). Regarding the fat-feed mixture, and feed matrices, there was a fluctuation in the survival rate of Salmonella (all serovars) within each cycle. For the qualitative method, the 3 serovars persisted in all matrices until the end of the fourth cycle except for fat matrices. The present study highlights the ability of Salmonella to survive for a long time in different temperatures and matrices despite efficient cleaning and disinfection processes in the feeding lines, which may influence reinfection with Salmonella in poultry houses.

A K-Band Series-Fed WR42 Waveguide Horn Array with Beam Squint Reduction through Shunt Delay Sections

Series feeds are commonly used in antenna arrays because of their compact size and low loss compared to corporate feeds but typically feature beam squint over wide bandwidths. This work proposes a series-fed waveguide horn array with reduced beam squint by introducing synthesized time delay sections between the horns and the feed line. The array, implemented in a WR42 waveguide, achieves 1.53° beam squint over a 4 GHz operating band, compared to 10.52° for a reference design without time delay compensation.

Design and analysis of a super compact UWB antenna for accurate detection of breast tumors using monostatic radar‐based microwave imaging technique

AbstractThis article proposes a low‐profile ultra‐wideband (UWB) antenna for breast tumor detection using the monostatic radar‐based microwave imaging (RBMI) technique. The proposed UWB antenna consists of a circular patch and ground plane along with a modified tapered feed line having a total size of 13 × 9 × 1.6 mm3. The designed antenna operates from 4 to 11 GHz based on a −10 dB reflection coefficient with a peak gain of 9.5 dBi at 4.8 GHz. Experimental validation is carried out after fabricating the prototype of the UWB antenna and the breast mimic. The measured backscattered signals are captured using the vector network analyzer (E‐5063A) by keeping the antenna at 10 mm from the breast phantom. After that, post‐processing of the measured data is done to detect the exact depth and location of the malignant tissue. The proposed antenna uses UWB band frequency of operation because it has some unique features, that is, it provides immunity to multipath fading, has a simple design, has a low cost of fabrication, and has biological friendliness. Moreover, due to the proposed antenna's resonance at a lower resonant frequency better depth of penetration is achieved in human body phantoms and the proposed antenna provides specific absorption rates (SAR) of 0.877 W/kg over 1 g of tissue at 4.8 GHz, which is an acceptable limit for SAR as per FCC guidelines. Therefore, the proposed antenna and monostatic RBMI technique are good candidates for breast tumor detection.

A novel wideband dielectric resonator antenna with compact size

ABSTRACT In this paper, a wideband dielectric resonator antenna with compact size is presented. The proposed antenna is formed by four dielectrics. Non-adjacent dielectrics have same permittivity constant. A 50-ohm micro strip feed line is used to exciting the antenna through the coupling slot. By optimizing the dimensions and structure of the antenna, impedance bandwidth of 3.25 to 4.4 GHz is obtained. Impedance bandwidth of the proposed antenna is a very wide bandwidth compared to the previous dielectric antennas. The antenna gain is about 9.6 dB.

A Compact Modified Two-Arm Rectangular Spiral Implantable Antenna Design for ISM Band Biosensing Applications

This paper presents a new microstrip implantable antenna (MIA) design based on the two-arm rectangular spiral (TARS) element for ISM band (Industrial, Scientific, and Medical 2.4–2.48 GHz) biotelemetric sensing applications. In the antenna design, the radiating element consists of a two-arm rectangular spiral placed on a ground-supported dielectric layer with a permittivity of ϵr = 10.2 and a metallic line surrounding this spiral. Considering the practical implementation, in the proposed TARS-MIA, a superstrate of the same material is used to prevent contact between the tissue and the metallic radiator element. The TARS-MIA has a compact size of 10 × 10 × 2.56 mm3 and is excited by a 50 Ω coaxial feed line. The impedance bandwidth of the TARS-MIA is from 2.39 to 2.51 GHz considering a 50 Ω system, and has a directional radiation pattern with directivity of 3.18 dBi. Numerical analysis of the proposed microstrip antenna design is carried out in an environment with dielectric properties of rat skin (Cole–Cole model ϵf (ω), ρ = 1050 kg/m3) via CST Microwave Studio. The proposed TARS-MIA is fabricated using Rogers 3210 laminate with dielectric permittivity of ϵr = 10.2. The in vitro input reflection coefficient measurements are realized in a rat skin-mimicking liquid reported in the literature. It is observed that the in vitro measurement and simulation results are compatible, except for some inconsistencies due to manufacturing and material tolerances. The novelty of this paper is that the proposed antenna has a unique two-armed square spiral geometry along with a compact size. Moreover, an important contribution of the paper is the consideration of the radiation performance of the proposed antenna design in a realistic homogeneous 3D rat model. Ultimately, the proposed TARS-MIA may be a good alternative for ISM-band biosensing operations with its miniature size and acceptable radiation performance compared to its counterparts.

Low-Profile Antenna System for Cognitive Radio in IoST CubeSat Applications

Since the CubeSats have become inherently used for the Internet of space things (IoST) applications, the limited spectral band at the ultra-high frequency (UHF) and very high frequency should be efficiently utilized to be sufficient for different applications of CubeSats. Therefore, cognitive radio (CR) has been used as an enabling technology for efficient, dynamic, and flexible spectrum utilization. So, this paper proposes a low-profile antenna for cognitive radio in IoST CubeSat applications at the UHF band. The proposed antenna comprises a circularly polarized wideband (WB) semi-hexagonal slot and two narrowband (NB) frequency reconfigurable loop slots integrated into a single-layer substrate. The semi-hexagonal-shaped slot antenna is excited by two orthogonal +/−45° tapered feed lines and loaded by a capacitor in order to achieve left/right-handed circular polarization in wide bandwidth from 0.57 GHz to 0.95 GHz. In addition, two NB frequency reconfigurable slot loop-based antennas are tuned over a wide frequency band from 0.6 GHz to 1.05 GH. The antenna tuning is achieved based on a varactor diode integrated into the slot loop antenna. The two NB antennas are designed as meander loops to miniaturize the physical length and point in different directions to achieve pattern diversity. The antenna design is fabricated on FR-4 substrate, and measured results have verified the simulated results.

CPW fed shovel shaped super wideband MIMO antenna for 5G applications

A shovel shaped antenna operating from 4.1 to >60 GHz to cover C/X/Ku/K/Ka/Q/U bands along with 5G bands n257/n258/n259/n260/n261/n79/60 GHz is presented in this paper. It consists of a modified square patch, tapered feed line and modified defected coplanar waveguide ground planes. A half-wavelength split ring resonator (SRR) is used to achieve X-band satellite downlink (6.8–7.8) GHz band notch. It has dimensions of 20 × 14 mm2, quasi-stable radiation patterns, a maximum peak realized gain of 9 dBi, fidelity factor > 50%, |S21| > 32 dB and linear S21 phase response. It’s two element spatial diversity configuration has footprint of 20 × 36 mm2, operating bandwidth of 4.3 to >60 GHz with notch band characteristics and isolation >15 dB due to hybrid decoupling structure. The pattern diversity configuration has footprint of 20 × 41.5 mm2, impedance bandwidth of 4.3 to >60 GHz for Port 1 & 3.9 to >60 for Port 2 and isolation >21 dB due to hybrid decoupling structure. Both MIMO antennas have ECC≤0.01, DG≅10, TARC < -10 dB, ηmux > -3.5 dB and CCL≤0.3 b/sec/Hz and channel capacity of ∼11.34b/sec/Hz. The proposed antenna geometries are dominating previously reported structures in terms of superwide bandwidth, compact dimensions, high BDR ∼3335, high peak gain and good diversity performance with less intra element spacing.

Increasing the efficiency of Siberian sturgeon juveniles growing on industrial feeding line by enriching of base feeds with dry garlic powder and humic preparation from peat

Of all representatives of sturgeon aquaculture, Siberian sturgeon Acipenser baerii occupies about 40% of its volume and is grown in 50 countries, including Russia. In 2018, the volume of commercial biomass production of this fish in the world was estimated at about 22–23 thousand tons [17]. In order to increase the efficiency of industrial production of this fish in aquaculture in the extreme conditions of Siberia, it is advisable to use feeds enriched with non-toxic components of natural origin, which increase the viability and productivity of objects and have no adverse affect to products quality and environment. In aquaculture, including sturgeons, the phytobiotic garlic and complex organic molecules of humic compounds are used for this purpose. In this experiment the industrial factory feeds, enriched with the humic additive Humiton from peat at a dose of 25 ml/kg of feed and/or dried garlic powder at a dose of 30 g/kg was used. The effectiveness of these feeds was evaluated for training of the rearing stock of Siberian sturgeon juveniles for maintenance in cages in winter conditions, depending on the initial weight of the objects. In sturgeons with a higher initial weight, by the end of the experiment, the use of feeds enriched with each of the components was effective in terms of safety, weight gain and improvement in the feed conversion rate FCR against the background of cold stress. In small fish, the main effect was an improvement in FCR when fed with garlic powder.

CSRR Structure Design for NV Spin Manipulation with Microwave Strength and Fluorescence Collection Synchronous Enhancement.

In this work, we designed, simulated, and tested a complementary split ring resonator (CSRR) for the purpose of applying a strong and uniform microwave field for the manipulation of nitrogen vacancy (NV) ensembles. This structure was fabricated by etching two concentric rings on a flat metal film that was deposited on a printed circuit board. A metal transmission on the back plane was used as the feed line. The fluorescence collection efficiency was improved by about 2.5 times with the CSRR structure compared to that without CSRR. Furthermore, the maximum Rabi frequency could reach 11.3 MHz, and the Rabi frequency variation was smaller than 2.8% in an area of 250 × 75 μm. This could pave the way to achieving high-efficiency control of the quantum state for spin-based sensor applications.