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A vertically stacked, three layer hybrid Hilbert fractal geometry and serpentine radiator-based patch antenna is proposed and characterized for medical implant applications at the Industrial, Scientific and Medical band (2.4-2.48 GHz). Antenna parameters are optimised to achieve miniaturized, biocompatible and stable transmission characteristics. The paper aims to discuss these issues.

Human tissue effects on the antenna electrical characteristics were simulated with a three-layer (skin, fat and muscle) human tissue model with the dimensions of 180×70×60 mm3 (width×height×thickness mm3). Different stacked substrates are utilized for the satisfactory characteristics. Two identical radiating patches are printed on Roger 3,010 (ε _r=10.2) and Alumina (ε _r=9.4) substrate materials, respectively. In addition, various superstrate materials are considered and simulated to prevent short circuit the antenna while having a direct contact with the metallization, and achieve biocompatibility. Finally, superstrate material of Zirconia (ε _r=29) is used to achieve biocompatibility and long-life. A finite element method is used to simulate the proposed hybrid model with commercially available Ansoft HFSS software.

The antenna is miniaturized, having dimensions of 10×8.4×2 mm3 (width×height×thickness mm3). The resonance frequency of the antenna is 2.4 GHz with a bandwidth of 100 MHz at return loss (S11) of better than −10 dB characteristics. Overall, the proposed antenna have 50 Ω impedance matching, −21 dB far field antenna gain, single-plane omni-directional radiation pattern properties and incident power of 5.3 mW to adhere Specific Absorption Rate regulation limit.

Vertically stacked three layer hybrid design have miniaturized characteristics, wide bandwidth, biocompatible, and stable characteristics in three layer human tissue model make this antenna suitable for implant biomedical monitor systems. The advanced simulation analysis of the proposed design constitutes the main contribution of the paper.

This paper aims to present the design, fabrication and analysis of a wideband, enhanced gain 1 × 2 patch antenna array with a simple profile structure to meet the desired antenna traits, such as wide bandwidth, high gain and directional patterns expected for the upcoming fifth-generation (5G) wireless applications in the millimeter wave band. To enhance these parameters (bandwidth and gain), a new antenna geometry by using a T-junction power divider is presented.

The theory behind this paper is connected with advancements in the 5G communications related to antennas. The methodology used in this work is to design a high gain array antenna and to identify the best possible power divider to deliver the power in an optimized way. The design methodology adopts several steps like the selection of proper substrate material as per the design specification, size of the antenna as per the frequency of operation and application-specific environment condition. The simulation has been performed on the designed antenna in the electromagnetic simulation tool (high-frequency structure simulator [HFSS]), and optimization has been done with parametric analysis, and then the final array antenna model is proposed. The proposed array contains 2-patch elements excited by one port adapted to 50 Ω through a T-junction power divider. The 1 × 2 array configuration with the suggested geometry helps to improve the overall gain of the antenna, and the implementation of the T-junction power divider provides enhanced bandwidth. The proposed array designed using a 1.6 mm thick flame retardant substrate occupies a compact area of 14 × 12.14 mm².

The prototype of the array antenna is fabricated and measured to validate the design concept. A good agreement has been reached between the measured and simulated antenna parameters. The measured results confirm its wideband and high gain characteristics, covering 24.77–28.80 GHz for S₁₁= –10 dB with a peak gain of about 15.16 dB at 27.65 GHz.

The proposed antenna covers the bandwidth requirements of the 26 GHz n258 band (24.25–27.50 GHz) to be deployed in the UK and Europe. The suggested antenna structure also covers the federal communications commission (FCC)-regulated 28 GHz n261 band (27.5–28.35 GHz) to be deployed in America and Canada. The low profile, compact size, simple structure, wide bandwidth, high gain and desired directional radiation patterns confirm the applicability of the suggested array antenna for the upcoming 5 G wireless systems.

As Asian telecommunications markets become liberalized, there will be significant impact on the design and management of telecommunications space and pathways. Details of the impact will vary according to each country’s unique approach to liberalization and according to tenants’ expectations with regard to an increasingly competitive telecommunications market. This article explores via each element of telecommunications space and pathways how liberalization of the telecommunications market in Hong Kong is being used as a catalyst to improve services and competitiveness of commercial buildings owned and operated by Hongkong Land Ltd, a major developer of grade A office space in Asia.

It was a good Farnborough Show … for those who went to see the flying displays and the weather was a great consolation. But it was an unusual Farnborough in some respects, first because of the good weather and this does bear repetition, and it does make such a difference to setting up the Show to its progress through the week and to the mood of the people there.

The proposed metamaterial absorber (MMA) has the following advantages: first, the structure of the MMA consists of one planar metallic resonator, which presents a new design approach to obtain a multiband absorption response, rather than using multiple unit-cells in the one large unit cell or stacking different layers. Second, the simultaneous realization of triple-band and dual-band absorption (or bi-functional absorption) at five different frequencies can integrate the respective advantages of the triple functions of the triple-band MMA and double-band MMA, and therefore, the bi-functional MMA will find more application prospects than multiple-functional devices of triple-band and dual-band. Third, the authors simulated the three combinations of MMA here, which is indium tin oxide (ITO)-Polyimide-ITO, ITO-Teflon-ITO and ITO-polyethylene terephthalate (PET)-ITO for the same planar structure and achieve a high absorption rate. Finally, the proposed structure is polarization and angle independent in nature.

This absorption device consists of the top circular resonator, the middle insulating SiO₂ medium layer and the bottom metallic copper ground plane placed on a substrate. The conductivity of the copper metal is s = 5.8 × 10⁷ s/m. As the transmission of the MMA structure is zero, the substrate materials can be selected randomly. Totally four combinations of terahertz MMA are designed and simulated here which are ITO- SiO₂ –ITO, ITO-Polyimide-ITO, ITO-Teflon-ITO and ITO- PET-ITO for the same planar structure.

Compared with previous MMAs, the proposed MMA has the following advantages: First, the structure of the MMA consists of one planar metallic resonator, which presents a new design approach to obtain a multiband absorption response, rather than using multiple unit-cells in the one large unit cell or stacking different layers. Second, the simultaneous realization of triple-band and dual-band absorption (or bi-functional absorption) at five different frequencies can integrate the respective advantages of the triple functions of the triple-band MMA and double-band MMA, and therefore, the bi-functional MMA will find more application prospects than multiple-functional devices of triple-band and dual-band. Third, the authors simulated the three combinations of MMA here, which is ITO-polyimide-ITO, ITO-Teflon-ITO and ITO- PET-ITO for the same planar structure and achieve a high absorption rate. Finally, the proposed structure is polarization and angle independent in nature.

First, the structure of the MMA consists of one planar metallic resonator, which presents a new design approach to obtain a multiband absorption response, rather than using multiple unit-cells in the one large unit cell or stacking different layers. Second, the simultaneous realization of triple-band and dual-band absorption (or bi-functional absorption) at five different frequencies can integrate the respective advantages of the triple functions of the triple-band MMA and double-band MMA, and therefore, the bi-functional MMA will find more application prospects than multiple-functional devices of triple-band and dual-band. Third, the authors simulated the three combinations of MMA here, which is ITO-polyimide-ITO, ITO-Teflon-ITO and ITO-PET-ITO for the same planar structure and achieve a high absorption rate. Finally, the proposed structure is polarization and angle independent in nature.

The purpose of this study is to design a radio altimeter antenna whose production process is facilitated and can work with multiple-input multiple-output (MIMO) properties to provide space gain on the aircraft.

To create an easy-to-produce MIMO, a two-storied structure consisting of a reflector and a top antenna was designed. The dimensions of the reflector were prevented to get smaller to supply easy production. The unit cell nearly with the same dimensions of a lower frequency was protected through the original cell design. The co-planar structure with the use of a via connection was modified and a structure was achieved with no need to via for easy production, too. Finally, the antennas were placed side by side and the distance between them was optimized to achieve a MIMO operation.

As a result, an easy-to-produce, compact and successful radio altimeter antenna was obtained with high antenna parameters such as 10.14 dBi gain and 10.55 dBi directivity, and the conical pattern along with proper MIMO features, through original reflector surface and top antenna system.

Since radio altimeter antennas require high radiation properties, the microstrip antenna structure is generally used in literature. This paper contributes by presenting the radio altimeter application with antenna-reflective structure participation. The technical solutions were developed during the design, focusing on an easy manufacturing process for both the reflective surface and the upper antenna. Also, the combination of International Telecommunication Union’s recommended features that require high antenna properties was achieved, which is challenging to reach. In addition, by operating the antenna as a successful MIMO, two goals of easy production and space gain on aircraft have been attained at the same time.

Airliners carrying between 800 and 1,000 passengers, weighing between 1m and 1.5m lb at take‐off may become a reality after 1980, according to Gordon Sim, director of science and engineering at Lockheed‐California Co. His prediction is based on a Lockheed study forecasting air passenger traffic growing at 11.4 per cent through the 1970's, 9.1 per cent through the 1980's and 66 per cent in the 1990's. While he believes aircraft technology is available to build this size airliner, producing an engine with the necessary thrust of about 90,0001b for a four engined aircraft may not be so easy, specially when taking into account noise levels. Mr Sim sees little significant penetration of V/TOL or S/TOL aircraft into the market before 1980 due to slow growth. Even then the relatively high operating costs would be rivalled by conventional wide‐bodied aircraft which will be designed with more advanced high‐lift systems for reduced take‐off and landing.

NOT perhaps the most vintage of Farnboroughs from the point of view of new aircraft and new technology, but undoubtedly one of the most successful in relation to the business done. Some fifteen major orders worth over £32½ million were announced, bringing the total order book for the industry this year to more than £782 million already. This exceeds by a handsome margin the new business won by the industry in any nine‐month period in the past, and it is expected that by the end of the year orders worth well over £800 million will have been received. Highlights of the new British hardware on show were the Hawker Siddeley Nimrod and production Harriers on the military side; the B.A.C. One‐Eleven 500, the Handley Page Jetstream, the Garrett‐engined Short Skyvan, and the Beagle Pups showed the resurgence of the industry's civil interests. The number of foreign aircraft that appeared, sponsored in the main by Rolls‐Royce, bore witness to the strength of Britain's aero engine and aircraft equipment industry, and further evidence of this was found in the exhibition proper with many examples of major items of equipment having been adopted for overseas markets. The overall impression at Farnborough was a new‐found confidence in the future of the industry exemplified by a more aggressive and effective export sales policy that has already proved our ability to deliver the goods. It is not possible to cover all the exhibits shown at Farnborough, but the report following describes many of the interesting items.

THE centripetal forces at work in the world seem to draw all human associations into larger groups. Work Study has been no exception to this, as the formation of a European Federation six months ago indicates. Another manifestation of the same tendency is the letter we print from a correspondent suggesting that there is only room for one professional organisation for Work Study in this country.

The purpose of this paper is to describe recent research involving the application of biomimetic design concepts to nanosensor developments.

Following a short introduction to nanobiomimetic concepts, this paper discusses a range of recent nanosensor developments whose designs mimic or use naturally‐occurring nanostructures or nanomaterials.

This shows that biomimetic design concepts are being applied to a range of nanosensors which have been shown to respond to a range of physical and chemical variables, often with very high sensitivities. Potential applications include homeland security and military uses, healthcare and robotics.

This paper provides details of recent nanobiomimetic sensor research which has potential in a range of critical applications.