A compact 5GHz WLAN notched bluetooth/UWB antenna

A Compact dual slot ultra-wide band (UWB) Antenna for WLAN and X-Band applications is proposed. The projected antenna is designed for the planar ultra-wide band (UWB) antenna and ultra-wide band (UWB) with two band dismissals. The proposed antenna overall size is 30x40x1.6. The antenna comprises of Rectangular patch imprinted on the Flame Resistant (FR4) substrate with 50Ω input impedance. FR-4 is a composite material made out of fiberglass fabric woven with an epoxy pitch cover that is fire safe (self-dousing). "FR" implies fire resistant, and means that the material meets the standard. This patch consists of dual slot one for WLAN and one for X-band Satellite Communication System. The antenna intended with return loss (RL) >= 10db and frequency ranges between 3.1 to 10.6 GHz with VSWR<2. The antenna works for the applications of wireless local area network (WLAN) system (5.15 – 5.825 GHz), X-band downlink (7.25 - 7.75). The ultra-wide band frequency range for these wireless systems causes interference. To reduce the interference, band notching is done. The WLAN and X-Band satellite communication system bands are forbidden by inserting slots in the patch. The proposed antenna is having high gain at the pass bands while a sharp drop at the forbidden bands.

In this paper a systematic model is used to find a closed-form formula for the channel capacity of ad hoc networks with line topology based on Ultra-Wideband (UWB) and Wireless Local Area Network (WLAN) technologies. As a result, it has been found that the interference level in this network topology is upper bounded and a formula to compute this limit is provided. Based on our computations, it is shown that UWB ad hoc networks have much larger channel capacity than WLAN ad hoc networks. With UWB technology the maximum throughput per node is limited by the transmission bit rate while it is limited by the low channel capacity when WLAN technology is used. As a minor advantage of our findings, a clue about routing algorithm optimization is also given.

In this paper, a closed form expression for the bit error rate performance of the multi-band orthogonal frequency division multiplexing (MB-OFDM) ultra wideband (UWB) communication system in the presence of interference is analytically analysed. The considered channel is the Saleh-Valenzuela multipath fading channel model. The interference is modelled as the OFDM-based IEEE802.11n wireless local area networks (WLANs). The dependence of the bit error rate performance of the MB-OFDM UWB communication system on the transmission range along with the impact of interference is also analytically investigated. Numerical results are validated with the aid of simulations. It is shown that the range performance of the MB-OFDM UWB communication system is severely deteriorated due to the presence of such interference.

Ultra Wideband (UWB) technology is a potential technology for short range communication with high data rate and relatively small amount of transmitted power. The coexistence of UWB systems with other narrowband systems make UWB systems prone to interference because of low transmission power limits. In this paper, we propose a technique to mitigate the effect of interference from IEEE 802.11a wireless local area network (WLAN) using method of template waveform processing. We use Fourier transform to approximate the template at the receiver. We approximate the template by two methods as a sum of subcarriers at different frequencies except the interfering frequencies and original template with removal of interfering frequencies. We compare the proposed interference mitigation technique with Gabor approximation method proposed by K. Ohno and T. Ikegami to show better interference rejection using proposed technique.

A compact coplanar waveguide fed UWB (ultra-wideband) antenna with triple band-notched characteristics is presented. The rectangle radiation patch is used in the new design, and the bandwidth of the UWB antenna is extended by using circle corner for the rectangle cut from the ground. A parasitic element is added, whereas an inverted U-shaped slot is cut on the top of the CPW ground plane and a U-shaped slot is cut on the rectangle radiation patch. As a result, a triple band-notched characteristic is obtained, by which the potential interference between UWB and WLAN (Wireless Local Area Networks), C-band and X-band systems can be effectively reduced.

Millimeter-wave (mmw) frequency bands, especially 60GHz unlicensed band, are considered as a promising solution for gigabit short range wireless communication systems. IEEE standard 802.11ad, also known as WiGig, is standardized for the usage of the 60GHz unlicensed band for wireless local area networks (WLANs). By using this mmw WLAN, multi-Gbps rate can be achieved to support bandwidth-intensive multimedia applications. Exhaustive search along with beamforming (BF) is usually used to overcome 60GHz channel propagation loss and accomplish data transmissions in such mmw WLANs. Because of its short range transmission with a high susceptibility to path blocking, multiple number of mmw access points (APs) should be used to fully cover a typical target environment for future high capacity multi-Gbps WLANs. Therefore, coordination among mmw APs is highly needed to overcome packet collisions resulting from un-coordinated exhaustive search BF and to increase total capacity of mmw WLANs. In this paper, we firstly give the current status of mmw WLANs with our developed WiGig AP prototype. Then, we highlight the great need for coordinated transmissions among mmw APs as a key enabler for future high capacity mmw WLANs. Two different types of coordinated mmw WLAN architecture are introduced. One is distributed antenna type architecture to realize centralized coordination, while the other is autonomous coordination with the assistance of legacy Wi-Fi signaling. Moreover, two heterogeneous network (HetNet) architectures are also introduced to efficiently extend the coordinated mmw WLANs to be used for future 5th Generation (5G) cellular networks.

An ultra-wideband (UWB) short range communication system is investigated in this paper. The system is based on an on-off-keying (OOK) modulation where the transmitted data pulse is obtained by using a set of orthogonal frequency (OF) signals. This optimizes the transmitted signal power and maximizes the equivalent signal-to-noise ratio (SNR) at the receiver. The receiver uses a non-coherent energy detector. The system was tested in real communication environment. The radio frequency (RF) band from 3.7 to 4.3 GHz was used. In line-of-sight (LOS) mode and at a distance of 5 m a data rate of 20 Mbit/s was achieved without forward error correction code. The motivation of this work is to provide a non-expensive, medium data rates, and low-power short-range radio communication system suitable for personal area network (PAN) applications.

We propose a slot antenna consisting of a rectangular slot on the ground plane, fed by a microstrip line with a rectangular-ring-shaped tuning stub that can be deployed in ultra-wideband (UWB) communication systems to avoid interference with wireless local area network (WLAN) communication. Our antenna can achieve a single band-notched property from the 5 GHz frequency to the 6 GHz frequency owing to a controllable band notch that uses L- and J-shaped parasitic elements. The antenna characteristics can be modified to tune the band-notched property (4 GHz to 5 GHz or 6 GHz to 7 GHz) and the bandwidth of the band notch (1 GHz to 2 GHz). Furthermore, the shifted notch with enhanced width of the band notch from 1 GHz to 1.5 GHz is described in this paper. The UWB slot antenna and L- and J-shaped parasitic elements also provide the band-rejection function for reference in the WiMAX (3.5 GHz) and WLAN (5 GHz to 6 GHz) regions of the spectrum. Experiment results evidence the return loss performance, radiation patterns, and antenna gains at different operational frequencies.

A novel and compact planar ultra wide band (UWB) filter is presented. Stepped impedance resonator (SIR) is used as multi mode resonator (MMR). MMR is fed by inter digital coupled lines. Coupled lines are designed such that to ensure low insertion loss over a wide frequency range. SIR (i.e., MMR) produces three resonant modes in the UWB frequency range ensures wide pass band. To avoid the potential interference caused by the co-existing wireless services is mitigated by incorporating band notch characteristics. In addition to UWB pass band, GSM 1800 band for GSM mobile communication with center frequency at 1850MHz is also achieved. Filter exhibits narrow pass band from 1800MHz to 1950MHz and UWB pass band from 3.5 GHz to 10 GHz with reference to 3 dB. At band notch frequency filter exhibits high attenuation level up to 40 dB and ensures less interference caused by co-existing wireless local area network (WLAN) band from 5.6 GHz to 5.9 GHz. GSM 1800 Band is obtained by loading shorted stub to the MMR without disturbing the UWB pass band response. S-parameters of the filter depict good UWB characteristics along with GSM 1800 pass band. Proposed filter is designed based on RT/Duroid 5880 substrate with dielectric constant 2.2 and thickness 0.785 mm. Proposed filter design is aimed to be a compact over reported UWB filter (i.e., surface area of 0.24λ 0 × 0.14λ 0 (Where λ 0 is the free space wavelength at the 6.85 GHz)).

This paper presents frequency band-notched antenna to overcome electromagnetic interference (EMI) between UWB systems and Wireless Local Area Networks (WLANs) based on IEEE 802.11a standard for Ultra Wide-Band (UWB) communication. The proposed antenna is designed on FR4 substrate having a size of 12×18 mm2 with thickness of 1.6 mm and relative permittivity (er) of 4.4 which provides frequency notching from 4.9 to 6.2 GHz. This antenna consists of two conducting strips inside a rectangular slot printed on circular shaped patch. This antenna provides a wide band width from 4.4 to 11.2 GHz with single band frequency notch from 4.9 to 6.2 GHz to avoid interference of UWB band with the existing systems. The design parameters and the performance of the proposed antenna are analyzed by using HFSS. The antenna displays a good omnidirectional radiation pattern and gain.

Ultra wideband (UWB) is a promising technology in delivering high data rate for short range wireless communication systems. Because of their large bandwidth, UWB signals may encounter some problems especially with high sampling rate requirements. Moreover, coherence existence with other narrowband systems is a major concern which needs to be addressed through proper mechanisms. The problem becomes so complex if multiple users exist. Since narrowband interference (NBI) signals have sparse representation in the discrete cosine transform (DCT) domain, they can be estimated and suppressed using Compressive Sensing (CS). CS also has the ability to reduce the high sampling rate requirements. For training based NBI mitigation with CS, three groups of pilot symbols are used to estimate the NBI signal subspace, the UWB signal subspace, and to provide information about the channel. In this paper, the distribution of pilot symbols among the three groups is investigated in the presence of strong NBI. The investigation is based on the bit error rate performance and throughput. The influence of each pilot symbols group is studied. The performance is also evaluated in the presence of multiuser interference in addition to the NBI. Simulation results show that the size of the third group of pilot symbols which is used to estimate the channel is the most dominant one.

This paper presents results of coexistence measurement studies between multiple ultra wideband (UWB) transmitters and a global positioning system (GPS). In addition, mathematical models for UWB aggregate noise rise in the GPS, universal mobile telecommunications system (UMTS) and wireless local area network (WLAN) 802.11a/g bands are illustrated. In GPS coexistence measurements, a realistic satellite constellation and outward circumstances were created using a commercial GPS simulator and receiver. Each measurement was carried out using Federal Communications Commission (FCC) compatible prototype singleband UWB transmitters. The measurements took place in an anechoic chamber to minimize any radio interference. The results clearly show that GPS can survive even under a large number of interfering UWB devices which are operating using realistic transmission parameters. Still, if a large number of interfering UWB devices or high UWB activity factor and pulse repetition frequency is used UWB can be regarded as a threat to GPS usage.

This article presents a new design of ultrawideband (UWB) microstrip slot antenna with band-notched function around 5–6 GHz to avoid any interference from the wireless local area network (WLAN) systems. The proposed antenna consists of a square radiating stub with a rotated C-ring slot, a feed-line and a slotted ground plane with an S-shaped parasitic structure inside an extra rectangular slot. By cutting a rectangular slot on top of the ground plane and also by embedding an S-shaped parasitic structure inside the slot, a new resonance at the higher frequencies is excited and hence much wider impedance bandwidth can be produced, which provides a wide usable fractional bandwidth of more than 135%. In the proposed design, to generate the WLAN band-stop property, the rotated C-ring slot was inserted at the radiating stub. Simulated and measured results are presented to validate the usefulness of the proposed antenna structure for UWB applications. The proposed monopole antenna configuration is simple, easy to fabricate and has a small size of 20 × 20 × 0.8 m3. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:1744–1747, 2014

Mobile Ad hoc Networks (MANETs) have witnessed an increasing amount of interest during the last decade. Hosts (or nodes) within the network are mobile, and each node is equipped with a short range transmitter and receiver, antenna, and local power supply. Nodes then operate as a router to relay messages from the sender to the receiver, and they can be organised into different topologies; for example: they can be flat or hierarchical, they can move in any direction and speed, and they can communicate with each other through wireless routing protocols. More recently, systems based on Ultra-WideBand (UWB) technology have become a promising candidate in application to MANETs. This is mainly due to their powerful capabilities, such as their high data rates and low power consumption, and although many routing protocols have been designed for ad-hoc networks, few have considered their application to UWB based MANETs. This paper presents a review of different types of wireless routing protocols for MANETs with a concluding emphasis on their application to UWB based systems.

There is a speedy development withinside the place of broadband wi-fi communications as the global call for in elevating for large bandwidth and extra mobility. The speedy increase withinside the previous few a long time withinside the WAN's and LAN's is particularly because of growing improvement in excessive potential and occasional loss optical fiber. But, the main downside in optical fiber cable communique is that optical fiber receives broken in a long-haul installation. Thus, underwater communication has paved the way for overcoming this disadvantagefor programs of underwater statement and sea monitoring, the importance of underwater wi-fi optical communication has expanded. Attenuation and fading of light propagation, as well as impairment in the performance of underwater wireless optical communications, are caused by elements such as underwater absorption, scattering, and turbulence (UWOC). UWOC is a short-range wireless communication system that allows for greater data throughput than classic acoustic communication systems while using less power and posing fewer computing problems. The main challenge for underwater wireless communication, on the other hand, is from the fundamental properties of ocean or sea water. Understanding the feasibility and minimising the BER, as well as boosting the reliability of high data rate underwater communication lines, is the main topic of this paper. This study's purpose is to conduct underwater optical communication research while also producing new ideas to aid in the development of future underwater communication systems.