Hamsakutty Vettikalladi

High-Efficient and High-Gain Superstrate Antenna for 60-GHz Indoor Communication

A high-efficient and high-gain aperture coupled patch antenna with superstrate at 60 GHz is studied and presented. It is noted that adding superstrate will result in a significant effect on the antenna performances, and the size of the superstrate is critical for the optimum performance. The maximum measured gain of a single antenna with superstrate is 14.6 dBi, which is higher than that of a classical 2 x 2 array. It is found that the gain measured of a single antenna with superstrate increases nearly 9 dB at 60 GHz over its basic patch antenna. This superstrate antenna gives a very high estimated efficiency of 76%. The 2:1 measured VSWR bandwidth with superstrate is 6.8%. The radiation patterns are found to be broadside all over the frequency band. Also, this letter explains a comparison to another source of parasitic patch superstrate antenna with normal microstrip coupling. It is found that aperture coupling is better for high-gain antenna applications.

Wideband and high efficient aperture antenna with superstrate for 60 GHz indoor communication systems

The 60 GHz millimeter wave (MMW) radio technology is a promising candidate for fulfilling the future needs for very high bandwidth wireless connections. It enables up to gigabit-scale connection speeds to be used in indoor WLAN networks or fixed wireless connections in metropolitan areas. Generally speaking, the more speed we need the more bandwidth we need. Transmission of several hundred megabits (or even several gigabit) per second requires very large bandwidth, which is available in the millimeter wave area. Large frequency range is allocated for unlicensed wireless telecommunications around 60 GHz (typically 59 – 66 GHz) all over the world, which makes the deployment of 60 GHz systems a lot smoother operation. In Europe the frequency ranges 62 – 63 GHz and 65 −66 GHz are reserved for wideband mobile networks (MBS, Mobile Broadband System), whereas 59 – 62 GHz range is reserved for unlicensed wideband wireless local area networks (WLAN); In the United States the frequency range 57 – 64 GHz is a generally unlicensed range; In Japan 59 – 66 GHz is reserved for wireless communications [1]. These new systems will need compact and high efficiency millimeter front-ends and antennas. For antennas, printed solutions are always demanding for the researchers because of its small size, weight and ease of integration with active components [2]. Conventional antenna arrays are used for high gain applications, but in these cases, arrays of large number of elements are required which induced an increase of the size of the antenna combined with a decrease of the efficiency [3],[4]. It has been reported that for high gain, a superstrate layer can be added at a particular height of 0.5 λ0 above the ground plane [5]-[7]. This solution enables an improvement in gain of nearly 4 dB over a single parasitic patch at 12 GHz [5] and 5 dB at 10 GHz [6], but 9 dB at 60 GHz with an optimised superstrate size [7]. In this paper, the authors are proposing a wideband, high efficient and high-gain aperture antenna with superstrate for 60 GHz communication. It is known that adding a superstrate with a specific size will induce a significant effect on antenna gain and radiation patterns. The maximum measured gain of a single aperture antenna with superstrate is 13.1 dBi, which is higher than that of a classical 2 × 2 array. The measured gain of a single antenna with superstrate compared to the basic aperture antenna shows an increase of 8 dB at 60 GHz. This superstrate antenna gives an estimated efficiency of 79%. The measured 2:1 VSWR bandwidth is 15%, that covers the 60 GHz application band, which is one advantage of this antenna configuration compared to reference [7]. The radiation patterns are found to be broadside all over the frequency band with very low back radiation. Hence aperture antenna with superstrate is a good candidate for wideband, high efficient high gain application at 60 GHz.

High gain and wide-band aperture-coupled microstrip patch antenna with mounted horn integrated on FR4 for 60 Ghz communication systems

A multi-layer antenna with high gain and wide bandwidth for 60 GHz Millimeter wave (MMW) applications is presented. The proposed antenna is a combination of aperture coupled microstrip patch antenna with an integrated Horn mounted on FR-4 substrate. The maximum size of the proposed antenna is 7.14mm × 7.14mm × 4mm. The design is optimized by means of parametric-variation. Investigations are made on the physical parameters of the proposed design by optimization, in order to achieve wide band and high gain millimeter wave antenna structure. The S11 bandwidth of the optimized antenna is 8.3% (57.4-62.4 GHz). The maximum gain and directivity of the proposed antenna is 11.65 dBi and 12.51 dBi respectively. The estimated efficiency is 82%. The proposed antenna finds application in V-band communication systems.

Millimeter Wave Antenna with Mounted Horn Integrated on FR4 for 60 GHz Gbps Communication Systems

A compact high gain and wideband millimeter wave (MMW) antenna for 60 GHz communication systems is presented. The proposed antenna consists of a multilayer structure with an aperture coupled microstrip patch and a surface mounted horn integrated on FR4 substrate. The proposed antenna contributes impedance bandwidth of 8.3% (57.4–62.4 GHz). The overall antenna gain and directivity are about 11.65 dBi and 12.51 dBi, which make it suitable for MMW applications and short-range communications. The proposed antenna occupies an area of 7.14 mm × 7.14 mm × 4 mm. The estimated efficiency is 82%. The proposed antenna finds application in V-band communication systems.

High Gain and High Efficient Stacked Antenna Array with Integrated Horn for 60 GHz Communication Systems

In order to achieve wide bandwidth and high gain, we propose a stacked antenna structure having a microstrip aperture coupled feeding technique with a mounted Horn integrated on it. With optimized parameters, the single antenna element at a center frequency of 60 GHz, exhibits a wide impedance bandwidth of about 10.58% (58.9–65.25 GHz) with a gain and efficiency of 11.78 dB and 88%, respectively. For improving the gain, we designed a 2 × 2 and 4 × 4 arrays with a corporate feed network. The side lobe levels were minimized and the back radiations were reduced by making use of a reflector at distance from the corporate feed network. The array structure resulted in improved gain of 15.3 dB with efficiency of 83%, while the array structure provided further gain improvement of 18.07 dB with 68.3% efficiency. The proposed design is modelled in CST Microwave Studio. The results are verified using HFSS, which are found to be in good agreement.

Substrate integrated waveguide antennas/array for 60 GHz wireless communication systems

A single layer substrate integrated waveguide (SIW) antennas/array for high speed 60 GHz communications, are presented. SIW based single antenna element and then two 1× 4 array are designed. Two types of feeding networks are designed for the array; a classical approach of microstrip lines and complete SIW based design. A comparison between the resulted radiation characteristics is performed. The back radiation phenomena is found to be high in the case of microstrip lines feeding network. This effect is minimized by introducing a complete SIW based feeding network. The gain of SIW single antenna element is 6 dBi having radiation efficiency 80 %. A gain of 11.2 dBi is achieved for each array design and an efficiency of 76 % and 73 % is achieved for 1×4 array with microstrip feeding network and a complete SIW feeding network, respectively. A low loss/cost substrate, RT duroid 5880 is used in the proposed designs.

BCB-Si Based Wide Band Millimeter Wave Antenna Fed by Substrate Integrated Waveguide

A benzocyclobutene (BCB) silicon (Si) based wideband antenna for millimeter wave applications is presented. The antenna consists of multilayer with one layer of BCB and the remaining three layers of Si. A patch is etched on the Si substrate above the air gap, which is excited through a slot. This architecture of slot, air gap, and patch will produce wide bandwidth by merging each one of resonances. The simulated results show that the antenna provides an  dB bandwidth of 9.7 GHz (17%) starting from 51.5 GHz to 61.2 GHz around 57 GHz central frequency. The antenna provides a maximum gain of 8.9 dBi with an efficiency of 70%.

A DR Loaded Substrate Integrated Waveguide Antenna for 60 GHz High Speed Wireless Communication Systems

The concept of substrate integrated waveguide (SIW) technology along with dielectric resonators (DR) is used to design antenna/array for 60 GHz communication systems. SIW is created in the substrate of RT/duroid 5880 having relative permittivity and loss tangent . H-shaped longitudinal slot is engraved at the top metal layer of the substrate. Two pieces of the DR are placed on the slot without any air gap. The antenna structures are modeled using CST Microwave Studio and then the results are verified using another simulation software HFSS. Simulation results of the two designs are presented; first a single antenna element and then to enhance the gain of the system a broadside array of is presented in the second design. For the single antenna element, the impedance bandwidth is 10.33% having a gain up to 5.5 dBi. Whereas in an array of elements, the impedance bandwidth is found to be 10.70% with a gain up to 11.20 dBi. For the single antenna element and antenna array, the simulated radiation efficiency is found to be 81% and 78%, respectively.

Nantenna for Standard 1550 nm Optical Communication Systems

Nanoscale transmission and reception technologies will play a vital role and be part of the next generation communication networks. This applies for all application fields including imaging, health, biosensing, civilian, and military communications. The detection of light frequency using nanooptical antennas may possibly become a good competitor to the semiconductor based photodetector because of the simplicity of integration, cost, and inherent capability to detect the phase and amplitude instead of power only. In this paper, authors propose simulated design of a hexagonal dielectric loaded nantenna (HDLN) and explore its potential benefits at the standard optical C-band (1550 nm). The proposed nantenna consists of “Ag-SiO2-Ag” structure, consisting of “Si” hexagonal dielectric with equal lengths fed by “Ag” nanostrip transmission line. The simulated nantenna achieves an impedance bandwidth of 3.7% (190.9 THz–198.1 THz) and a directivity of 8.6 dBi, at a center frequency of 193.5 THz, covering most of the ITU-T standard optical transmission window (C-band). The hexagonal dielectric nantenna produces modes and the wave propagation is found to be end-fire. The efficiency of the nantenna is proven via numerical expressions, thus making the proposed design viable for nanonetwork communications.

A dielectric loaded millimeter wave antenna array for 60 GHz communication systems

A Dielectric loaded millimeter wave antenna array of 1 × 4 elements fed by slotted substrate integrated waveguide for 60 GHz communication systems is presented. Only slotted SIW design cannot provide a wide bandwidth and hence to achieve wide bandwidth the concept of dielectric loading is adopted. The cumulative effect results in wide bandwidth. This design uses a complete SIW feed network to minimize the effect of back radiations. The results show an impedance bandwidth of 10.50 % around 60 GHz, having a gain up to 10.60 dBi, and an estimated efficiency of 75 %. The designs are simulated in CST Microwave Studio and verified in HFSS simulator.