On the Impact of Ultra-Wideband (UWB) on Macrocell Downlink of UMTS and CDMA-450 Systems

Results of the analytical analysis to assess the effect of the ultra-wideband (UWB) emissions on the [universal mobile telecommunication system (UMTS) and code division multiple access systems (CDMA-450)] are presented. The (UMTS and CDMA- 450 systems) normalized range and normalized capacity degradation are evaluated. A free-space propagation model is used to calculate the UWB signal power that interferes with both mobile systems. It is shown that, for the case of a single UWB transmitter, the UMTS can easily tolerate UWB interference when the UWB equivalent isotropically radiated power (EIRP) is -92.5 dBm/MHz or less for a distance between the UWB transmitter and the UMTS mobile of 1 m or higher. Also, it is shown that, for the case of multi-UWB transmitters, the UMTS can easily tolerate the UWB interference when the UWB EIRP is -94.5 dBm/MHz. For the single UWB transmitter case, the CDMA-450 downlink can tolerate UWB interference when the UWB power density is in the order of -106 dBm/MHz. For the case of multi-UWB transmitters, the power density that can be tolerated by the downlink of the CDMA- 450 system is in the order of -108 dBm/MHz

On the Impact of Ultra Wide Band (UWB) On Downlink Range of GSM-900 and DCS-1800 Systems

The effect of the UWB interference on the GSM-900 and DCS-1800 downlink is studied for different UWB power densities. For relatively high UWB power density (-60 dBm/MHz), the effect of the UWB signals is very high when the distance between the UWB transmitter and the GSM-900 or DCS-1800 receiver is less than 1 m. For low UWB power density (-91 dBm/MHz), the effect of the UWB signals is very small if the distance between the UWB transmitter and the GSM-900 or DCS-1800 receiver is 1 m or higher. It is found that the spectrum mask proposed by the FCC for indoor application (-53 dBm/MHz in the DCS-1800 band and -41 dBm/MHz in the GSM-900 band) is too high to be tolerated by the two mobile system

Performance of Hybrid Direct-Sequence Time-Hopping Ultrawide Bandwidth Systems over Nakagami-m Fading Channels

This paper investigates and compares the performance of various ultrawide bandwidth (UWB) systems when communicating over Nakagami-m fading channels. Specifically, the direct-sequence (DS), time-hopping (TH) and hybrid direct-sequence time-hopping (DS-TH) UWB systems are considered. The performance of these UWB systems is studied associated with employing the conventional single-user correlation detector or minimum mean-square error (MMSE) multiuser detector. Our simulation results show that the hybrid DS-TH UWB system may outperform a corresponding pure TH-UWB or pure DS-UWB system in terms of the achievable error performance. Given the total spreading gain of the hybrid DS-TH UWB system, there is an optimal setting of the TH spreading factor and DS spreading factor, which results in the best error performance

A complete CMOS UWB timed-array transmitter with a 3D Vivaldi antenna array for electronic high-resolution beam spatial scanning

We present a new Ultra Wide Band (UWB) Timed-\ud Array Transmitter System with Beamforming capability for\ud high-resolution remote acquisition of vital signals. The system\ud consists of four identical channels, where each is formed of a\ud serial topology with three modules: programmable delay\ud circuit (PDC or τ), a novel UWB 5th Gaussian Derivative order\ud pulse generator circuit (PG), and a planar Vivaldi antenna.\ud The circuit was designed using 0.18μm CMOS standard\ud process and the planar antenna array was designed with filmconductor\ud on Rogers RO3206 substrate. Spice simulations\ud results showed the pulse generation with 104 mVpp amplitude\ud and 500 ps width. The power consumption is 543 μW, and\ud energy consumption 0.27 pJ per pulse using a 2V power\ud supply at a pulse repetition rate (PRR) of 100 MHz.\ud Electromagnetic simulations results, using CST Microwave\ud (MW) Studio 2011, showed the main lobe radiation with a\ud gain maximum of 13.2 dB, 35.5º x 36.7º angular width, and a\ud beam steering between 17º and -11º for azimuthal (θ) angles\ud and 17º and -18º for elevation (φ) angles at the center\ud frequency of 6 GH