Wideband Local Area Network Research Articles

Compact dual-band-printed dipole antenna with parallel-winding lines and tapered structure for WLAN applications

In this article, a compact printed dipole antenna for wideband local area network (WLAN) (2.45/5.5 GHz) applications is presented.The proposed antenna consists of two radiating patches with several slots etched on the patches, which can generate parallel-winding lines and then produce two bands. By using the unique tapered structure, good impedance matching can be achieved in a wide dual-band without external matching circuit. For the experimental study, the antenna provides 10.2% bandwidth from 2.325 to 2.575 GHz and 64.9% bandwidth from 3.225 to 6.325 GHz (RL ≤ −10 dB). In addition, the antenna has good omnidirectional radiation patterns in H-plane and low cross-polarization levels in both E- and H-planes. The measured results are in good agreement with the simulation ones, and the experiment validates the design concept. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:2492–2494, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26342

Dual-band antenna design using M-shaped open stub

In this article, we have introduced dual-band antenna with M-shaped open stub for wideband local area network (WLAN)/ultra-wideband (UWB) applications. The M-shaped open stub is inserted into the proposed antenna for WLAN operation. The proposed antenna is fabricated and measured. Parametric studies and radiation characteristics for the designed antenna was simulated and measured. The designed antenna has the characteristics of wide bandwidth, dual-band, and negligible dispersion over the UWB band. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:455–458, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25729

Small-size 11-band LTE/WWAN/WLAN internal mobile phone antenna

This work presents an internal mobile phone antenna occupying a small board space of 600 mm2 on the system circuit board and providing three wide operating bands of at least 698–960, 1710–2690, and 5150–5825 MHz for the 11-band long term evolution (LTE)/ wireless wide area network (WWAN)/wideband local area network (WLAN) operation.This includes three LTE bands of LTE700/2300/2500, five WWAN bands of GSM850/900/1800/1900/UMTS, and three WLAN 2.4/5.2/5.8 GHz bands. The antenna is a coupled-fed shorted monopole, with a wide feeding strip in the coupling feed, a long shorting strip closely coupled to the shorted monopole, and a tuning stub connected to the shorting strip. The antenna's three wide operating bands are achieved and controlled by tuning the width of the feeding strip, the gap between the shorting strip and the shorted monopole, and the dimensions of the tuning stub. Operating principle of the proposed antenna is described in detail in this article. Results of the fabricated antenna are presented and discussed. The specific absorption rate results of the antenna with the presence of the user's head and hand are also studied. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2603–2608, 2010; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25526

Design of dual‐band antenna with U‐shaped open stub for WLAN/UWB applications

AbstractIn this article, we have proposed a dual‐band antenna with U‐shaped open stub for wideband local area network (WLAN)/ultra wideband (UWB) applications. The designed dual‐band antenna consists of two semicircle radiating patches, a rectangular slot separating the two semicircles, one step for impedance matching, and coplanar waveguide (CPW) feeding. Two kinds of prototypes (CPW‐fed UWB antenna and the dual‐band antenna with U‐shaped open stub) are fabricated and measured. Parametric studies and radiation characteristics for the two antennas are presented. The designed antenna has the figure‐of‐eight radiation pattern, wide bandwidth, and negligible dispersion over the operating frequency band. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 284–289, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24033

A Broadband Single-Stage Equivalent Circuit for Modeling LTCC Bandpass Filters

A single-stage equivalent circuit is proposed to model microwave bandpass filters (BPFs) fabricated in low-temperature co-fired ceramic (LTCC) technology up to several times its passband frequency. The equivalent circuit adopts a modified T topology with the expandable multilayer resonators to achieve an extremely large bandwidth. It can be efficiently established from the measured S-parameters using direct extraction or rational approximation. As a result, the modeled S-parameters for a 2.45-GHz wideband local area network (WLAN) LTCC BPF show good agreement with the measured results over a wide frequency range up to 8.5 GHz. Such a broadband model can be used to accurately predict the suppression of harmonics and interferences in system simulation of the WLAN front-end modules

Design of low-cost multimode fiber-fed indoor wireless networks

A low-cost option for transporting global system for mobile communication, Universal Mobile Telecommunication System and wideband local area network (WLAN) signals using multimode fiber (MMF) with 850-nm vertical-cavity surface-emitting lasers (VCSELs) is investigated through range predictions from a link budget analysis. These predictions are experimentally verified for WLAN signal transmission in an office environment, using a commercial access point and a 300-m (OM1/OM2) MMF link with low-cost 850-nm VCSEL transmitters. The analysis indicates that good performance and signal coverage is possible with optimum design of indoor fiber-fed wireless systems, even when using such inexpensive components

LOCNET--A local area network using optical switching

A wide-band local area network using optical switching is presently being developed by the Heinrich-Hertz-lnsitut in Berlin (West). To ensure high reliability the system will be implemented as a star type network, divided into two subsystems. All switching within the system will be done by optical switching techniques. The wide-band subsystem will use Lithium-Niobate switching matrix elements, interconnected as a multistage space switch. Thus bit rate independent channels will be available with the ability to establish various wide-band services of the in-house area. The second subsystem makes use of a single-mode star coupler. Distributed circuit switching with fast switching capability and flexible data rates will be implemented, utilizing a TDM frame, that supports 63 narrow-band connections and a capacity of 8 Mbit/s for fast data services. To prevent typical disadvantages of distributed switching like line tapping and system disturbance, caused by malfunctioning system components, LiNbO <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf> switches will be installed in front of and behind the star coupler. The single-mode star coupler will be implemented by cascading 2 × 2 star couplers, which are available as 3-dB couplers.