Rayleigh fade compensation QPRS coherent mobile radio modems operated at a practical 2 b/s/Hz efficiency

Abstract

For fast fading digital mobile systems, a s ec trally efficient technique that can achieve more ,Ran 2b/s/Hz with a built-in fade canceller is Recent studies show that fading in digital mo!%:g$ munications can be cancelled by adding redundant bits to the customer data or with Pilot-based techniques. The objective of this paper is to extend this concept to a more spectrally efficient class IV Quadrature Partial Response Signalin (QPRS) system. However, in such schemes if the ikt is corru ted by the phase noise caused by the plot-data interkrence, the fade cancellation will not effectively remove the error floor. The class IV system has an inherent advantage, in that it has a s ectral null at DC and a low ener y content at the en& of the band. Such systems also fave a higher speed tolerance. It is shown that a small bandwidth around DC can be vacated to insert the pilot. Our Ireliminary results indicate that the residual error oor can be reduced from lo-* to in fast fading channels. We show t h e imurovement in BER Derformance of the band-vacated QPRS compared i o -t h e unfiltered QPRS.

Multidimensional effects of biologically synthesized silver nanoparticles in Helicobacter pylori, Helicobacter felis, and human lung (L132) and lung carcinoma A549 cells

“…The bacterial cells were incubated with AgNPs for 12 h and then we measured the ROS production. The levels of ROS in AgNP-or H2O2-treated cells were higher, compared to the level of ROS in control cells [56]. H2O2 led to slightly higher ROS levels compared to the level of ROS in the AgNP-treated cells.…”

“…Cell viability was reduced as the concentrations of the AgNPs increased [8]. For each bacterial strain, no growth was observed at their respective MIC values.…”

“…Synthesis of AgNPs using leaf extract was performed according to a previously described method [8]. The leaf extract of A. princeps was used as both a reducing and stabilizing agent.…”

“…Figure 2 shows the XRD patterns of dried AgNPs synthesized with A. princeps leaf extract. The XRD patterns indicated that the structure of AgNPs is face-centered cubic (fcc) [8,57]. The sharp XRD peaks at 2θ of 31.9 and 45.3 are attributed to the (111) and (200) crystallographic planes.…”

“…Capping agents are playing an important role for the stabilization of nanoparticles, for example, capped AgNPs exhibit better antibacterial activity than uncapped AgNPs do [6,7]. Biological methods seem to be valuable for the preparation of AgNPs with controlled size and shape of the nanoparticles [8][9][10][11][12][13]. Given that conventional physical methods have low yields and chemical methods are toxic and consume a lot of energy, the development of environmentally friendly approaches has become the more preferred trend for the field of nanobiotechnology.…”