The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
In case that a selfish terminal generates a large amount of traffic with high priority control of IEEE 802.11e, an access point (AP) and terminals in the AP cannot get transmission opportunities because of the media access control technique. In our previous work, we proposed traffic suppression method for the selfish terminal by cooperative controls between AP and terminals with considering the fairness...
In this paper a small size wideband planar inverted-F antenna (PIFA) is proposed which operates at 4G LTE (2.3–2.4 GHz) and (2.5–2.7 GHz), Bluetooth/WLAN (2.4–2485 GHz) and WiMAX (3.4–3.6 GHz) range. The proposed antenna has many advantages like small size and wide operation bandwidth. The antenna portion has dimensions as 20mm * 18mm and the overall dimensions are 44mm * 25mm * 0.8mm which can be...
There are some existing narrowband wireless systems over the designated ultra-wideband (UWB) operating band. To mitigate the potential interferences between UWB system and narrowband systems, a UWB antenna with dual band-notched characteristic is proposed. The antenna consists of a circular patch fed by a 50Ω microstrip line. An altered H-shaped slot is etched on the proposed radiator to introduce...
In this article, the ability of a single layer printed modified folded asymmetric dipole antenna, which is composed of two asymmetric radiated loops (there are slotted ground-trace in each loop) and asymmetric feeding structure, to operate at three wide frequency bands (2300∼2690MHz, 3000∼3600MHz and 4900∼6000MHz) to cover WLAN and LTE operation has been demonstrated. A prototype of the proposed antenna...
A planar ultra-wideband (UWB) antenna with quad notched bands is proposed and its performance is investigated in this paper. The designed UWB antenna consists of a rectangle-shaped radiating patch with tapers and a polygon ground plane with a rectangular slot. A rake-shaped resonator (RSR) and a pair of L-shaped slots (LSSs) are employed to achieve the desired four notched bands which are operated...
A novel compact printed antenna fed by CPW with WLAN band rejection for UWB applications is proposed in this paper. This symmetrical antenna features three parts: a semicircular stub as the UWB radiator, a pair of modified compact patches which are integrated smoothly as the ground plane with the line-to-arc transition structures, and two U-shaped slots which are embedded on the ground plane to reject...
The ultra-wideband (UWB) antennas are required to cover high impedance bandwidth such that the return loss (RL) is greater than 10 dB with improved gain and radiation efficiency which are required for the different applications. In this UWB range (3.1–10.6 GHz), there are other applications, using narrow band frequency bands, such as WiMAX (3.3–3.7) GHz, WLAN (5.15–5.825) GHz and others. In this case...
Frequency selective metamaterial-inspired antenna for dual-frequency operation incorporating two switches (SWs) has been proposed. Length of radiating element is varied which provides easy frequency re-configurability at WiMAX (3.5–3.57 GHz) and WLAN (5–5.5 GHz). The proposed antenna offers impedance bandwidths of 13.6% (at 3.39 GHz) and 17.2% (at 5.05 GHz) with average peak gains of 1.49 dB and 1...
Orthogonal Frequency Division Multiplexing (OFDM) is widely used in the wireless local area network (WLAN) standards like IEEE 802.11a/n/ac. OFDM has high spectral efficiency, enabling the high data rates required for video streaming and sharing of large files. However, the impact of analog front-end non-idealities in an OFDM system limits its performance. One such non-ideality is IQ imbalance. At...
A compact ultra-wideband multi antenna system is presented in this paper. The concept is based on the simultaneous excitation of different Characteristic Modes on each antenna element by multiple decoupled ports. This enables a 484 port antenna with low port to port coupling having only 121 physical antenna elements.
In recent years, the wireless local area networks (WLAN) access points (APs) are being deployed rapidly in the offices and the campuses to satisfy the quality of service (QoS) requirements such as network bandwidth. However, many empirical studies show that a large fraction of idle WLAN resources result in the significant energy losses. To reduce the energy consumption without violating the QoS requirement,...
Network selection is a key technology to realize fair resource allocation and load balancing for converged multi-radio heterogeneous networks. In this paper, we propose a Multiple attribute decision making and Evolutionary Game Theory (MEGT) integrated network selection scheme. In MEGT, utility functions are designed appropriately to compute user QoS satisfaction of the candidate network. User preferences...
In the paper we presents a dual-open-slot antenna, with a overall size of 50 × 13 × 3.5 mm3. The antenna consists of a long-open-slot and a short-open-slot. The tail of the long-slot is bent for compact size. The dual-slot antenna is feed by an L-shaped microstrip line. The long-slot used in the 2.4GHz mode and short slot excitation in 5.2 GHz mode. The open slots are excited through the L-shaped...
This paper presents a compact Stepped-impedance resonators (SIR) Vivaldi antenna for in-band notch adjustable characteristics. The main purpose of this design is the presentation of three parameter such as notch frequency adjustable, multi-band notch, stable gain. To avoid potential interferences, The proposed antenna has the capability to operate over the bandwidth 1.67–7GHz at return loss < −10...
A dual-band and dual-polarized fractal antenna for WLAN applications is presented in this paper. This design is based on the Sierpinski fractal antenna base station antennas. It is composed of two similar fractal antenna cross each composition. Antenna is composed of two different heights of the L-shaped feeder fed to achieve a dual polarization. The simulated and measured results show that the proposed...
The Handoff schemes should be seamless, only then can better service be provided. Hence for improved scheme we design a feasible handoff scheme for wireless heterogeneous networks. In the proposed handover method, a Vertical Handoff Manager (VHOM) is designed to control the handoff process based on the Markov Decision Process (MDP) in wide area network. In the proposed method STAs will choose the...
In modern mobile world interoperability between different wireless networks is most essential one, which enables the mobile node to move across the different heterogeneous wireless system. For seamless connectivity of mobile node mobility management and location management is essential one. In mobility management handoff estimation plays a vital role. To make the handoff estimation, attributes such...
We built up a Long Term Evolution (LTE) trial system operating in 5.8 GHz unlicensed bands and conducted a real time field trial in typical indoor environments. The user throughput of LTE with the 20MHz carrier in the unlicensed bands, which is used as a Supplemental Downlink (SDL) (always downlink), is evaluated and compared with that of Wireless Local Area Network (WLAN) with the same bandwidth...
In this paper, we present a CPW-fed crescent antenna for WLAN/Wi-Max applications. The antenna is fabricated using a flexible Rogers substrate, which can be mounted on any surface. The proposed antenna is composed of an outer circular slot with an inner circular patch, whose centers are non-coinciding. The patch has an additional horizontal slot along its diameter. The proposed antenna was simulated...
Compact ultra-wideband (UWB) antenna with dual band characteristics is presented. Simulation of the design is done using HFSS 12.1 and the return loss parameters of the design are presented. The design is an omega type in which by reducing the size and varying the centre position of the circle the dual band characteristics for the frequency of 3-3-5.1 GHz and 7.9–9.9 GHz with the bandwidth of 1.89...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.