نتایج جستجو برای: delay spread
تعداد نتایج: 236823 فیلتر نتایج به سال:
| A new model for the prediction of the field strength, the delay spread and the fast fading for mobile communication networks inside buildings is presented in this paper. In the first part of the paper, the equipment for the measurements is described. Some measurement results are shown to illustrate the performance of the measurement equipment. Based on the measurements a new parameter for the...
A high-speed triangular-modulated spread-spectrum clock generator using a fractional phase-locked loop is presented. The fractional division is implemented by a nested fractional topology, which is constructed from a dual-modulus divide-by-(N–1/16)/N divider to divide the VCO outputs as a first division period and a fractional control circuit to establish a second division period to cause the o...
Motivated by MIMO broad-band fading channel model, in this section we deals with the capacity behaviour of wireless MIMO and OFDM based spatial multiplexing systems in broad-band fading environments for the case where the channel is unknown at the transmitter and perfectly known at the receiver. This influence the propagation and system parameters on ergodic capacity, we furthermore demonstrate...
Spread-spectrum signals with long signature sequences are considered in this papez Particularly, a linear receiver proposed in [1] and [2] for direct-sequence spreadspectrum multiple access systems is extended to its iterative form. This extension is most applicable in situations with high processing gain, where it is necessary at times to use a large number of correlators to acquire the PN seq...
Using the wideband indoor channel measurements data at 2.4, 4.75 and 11.5 GHz of [1], a statistical Ultra Wide Band (UWB) channel model is determined. Employing different windows (i.e. Rectangular, Hanning and Blackman-Harris), the impulse response model for the UWB channel is obtained and accordingly, major channel parameters such as path loss exponent, shadowing, root mean square (rms) delay ...
We present the modeling of the frequency response of the channel for a radiating cable system by using an autoregressive model for an indoor environment. The coefficients of the autoregressive model are determined from the experimental channel frequency response. Measurements were carried out in an indoor environment, in particular on the second floor of a university building in the frequency r...
We investigated the capacity of internal border control to limit influenza spread in an emergent pandemic in the context of Australia, a country with a low-population density and geopolitical boundaries that may facilitate restrictions. Mathematical models were used to study the time delay between epidemics in 2 population centers when travel restrictions were imposed. The models demonstrated t...
We present a novel bandwidth (BW) efficient orthogonal frequency division multiplexing (OFDM) scheme with adaptive zeropadding (AZP-OFDM) for wireless transmission. Redundancy issues in OFDM based on cyclic prefix (CP), zero-padding (ZP), as well as no guard interval (NGI) systems are analyzed. A novel system design criterion based on the channel matrix condition is studied and applied to the d...
Orthogonal Frequency Division Multiplexing (OFDM) is a multi-carrier block modulation scheme suitable for wireless communications. It is primarily used in high bit rate systems to mitigate inter-symbol interference (ISI) caused due to delay spread. While the ISI caused by delay spread is an annoyance factor, it also provides multipath diversity advantage if the path gains fade independently. Fo...
In this paper an experimental characterization of a typical indoor wireless propagation channel is performed. This channel characterization is needed for short range applications (<10m), utilizing Ultra-Wideband Impulse Radio (UWB-IR) techniques. Both the line of sight (LOS) and the non line of sight (NLOS) scenarios are taken into account. The characterization is done using time domain measure...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید