Ultra wide band

Sana UllahΨ , Murad Ali+, Md. Asdaque HussainΨ, and Kyung Sup KwakΨ Ψ Graduate School of IT and Telecommunications, Inha University 253 Yonghyun-Dong, Nam-Gu, Incheon 402-751, South Korea. + KDI School of Public Policy and Management 87 Hoegiro ...

The propagation of ultra wide band (UWB) signals through walls is analyzed. For this propagation studies, it is necessary to consider not only propagation at a single frequency but in the whole band. The UWB radar output signal is formed by both transmitter and antenna. The effects of antenna receiving and transmitting responses for various antenna types (such as small and aperture antennas) are studied in the frequency as well as time domain. Moreover, UWB radar output signals can be sub- stantially affected due to electromagnetic wave propaga- tion through walls and multipath effects.

Four iterations of a Coplanar Waveguide (CPW)-Fed KOCH SNOWFLAKE fractal antenna are studied. Increasing the number of iterations allow us obtaining a simple and miniaturized antenna with good performances, operating for Ultra Wide Band (UWB) applications. The proposed antennas are a good solution for the 3.7-4.2GHZ C-Band, the 5.15-5.82 Wireless Local Area Network (WLAN), and for the 5GHZ Worldwide Interoperability for Microwave Access system (WIMAX) applications. The simulation was performed in FEKO 6.3.

In this paper, the Quality of Service (QoS) for multimedia traffic of the Medium Access Control (MAC) protocol for Ultra Wide-Band (UWB) networks is investigated. A protocol is proposed to enhance the network performance and increase its capacity. This enhancement comes from using Wise Algorithm for Link Admission Control (WALAC). The QoS of multimedia transmission is determined in terms of

— A complete 3.1-10.6 GHz ultra-wideband receiver using 500 MHz-wide sub-banded binary phase shift keyed (BPSK) pulses has been specified, designed and integrated as a three chip and planar antenna solution. The system includes a custom designed 3.1-10.6 GHz planar antenna, direct-conversion RF front-end, 500 MS/s analog to digital converters, and a parallelized digital back-end for signal detection and demodulation. A 100 Mb/s wireless link has been established with this chipset. A bit-error-rate (BER) of 10-3 was recorded at-80 dBm at a rate of 100 Mb/s for properly acquired packets in the lowest frequency band. Bit-scaling of the ADC from 1 to 5 bits reveals a 4 dB improvement in the link budget.

Qatial diversity is regarded as a passible mean to relax the stringent constraints imposed by regulationr on link budget for Ultra Wide Band (UWB) communications. A#er general considerations on the pehence of diversity for UWB signals. it is shown here by sirnulatiom on a test ...

Ahtract -A computer-aided sjnthesis design procedure is given for nonuniform quadrature directional couplers in inhomogeneous media. A wiggly geometry is employed which effective11 slows the odd-mode phase veloci5 to match the even-mode phase velocity. The wiggly ...

The present wireless communications must meet very strong conditions concerning the rate of data transmission, quality of service and electromagnetic compatibility. These requirements can be satisfy only by exploitation of families of complex radio signals, possessing special correlation properties. With regard, a method for synthesis of families of a class of ultra-wide band frequency hopping signals, called Costas arrays, is proposed in the paper. It is demonstrated that the method provides optimal correlation properties for all signals, belonging to a family of Costas arrays. The synthesized signals could be successfully applied in the wireless monitoring and control systems, ad hoc communication systems and so on.

A wideband direct-conversion RF front-end for Advanced Television Systems Committee terrestrial digital TV (DTV) tuner applications is realized in a 0.18-μm CMOS technology. In order to effectively solve the critical local oscillator (LO) harmonic mixing problem in an ultra-wideband frequency environment of 48-860 MHz, the combination of a mismatch calibrated harmonic rejection mixer (HRM) and a simple preceding integrated third-order

Abstract— Wireless Personal Area Network System becomes popular in replacing a wire technologies for short area range communication system. Technologies such as Bluetooth, Wi-Fi and ZigBee are used for this purpose but due to their low transfer data rates they are unable to handle ...

When a typical narrowband antenna is excited by an ultra-wideband (UWB) impulse, the antenna rings at its resonant frequency, stretching out the waveform in time. A resonant antenna, like the bow tie, discone, or bicone have been available for years. A bow tie has a relatively high input impedance, and requires a matching balun to make it useable with a

A compact microstrip parallel coupled line filter for ultra wide band applications by means of combining a network of coupled line and defected ground is proposed. The design equations for three and five interconnected networks are derived and implemented. Simulations for three different configurations for filters are optimized. Then three prototype circuits are constructed, a bandpass filter with center frequency 2.25 GHz and two different bandpass filters (in terms of perturbations) with center frequencies 2.33GHz. For 2.25 GHz circuit wide fractional bandwidth of about 90% is obtained but undesired high return loss existed. For 2.33GHz circuit with grooves in sides fractional bandwidth of about 60% is obtained at about 3.4 GHz center frequency. However undesired return loss existed for this circuit whereas good out off band performance is achieved. For 2.33GHz circuit with grooves in whole sections the center frequency got shifted to about 3.4 GHz and about 50% fractional bandwidth is obtained with very good out off band performance observed.

Abstract—Ultra Wide Band (UWB) systems based on Multiband Orthogonal Frequency Division Multiplexing (MB-OFDM) modulation, similarly to traditional OFDM systems, are particularly sensitive to oscil-lators instability, as carrier and sampling frequency offsets between the ...