Plasma Antennas

We have demonstrated that one or two plasma tubes can be used to focus, spread, and steer antenna beams. We have also shown that we can simulate convex and concave plasma lenses by using cylindrical plasma tubes. Focusing by a plasma is useful because it can be used to increase the gain of an antenna, and to quickly reconfigure the beamwidth as needed without physically moving the antenna. With this technology, there is no need for phased arrays to steer and focus an antenna beam. Beam steering with a plasma allows tuning to different frequencies which is a difficult task for standard antennas. Our experimental results with 44 GHz showed a dramatic improvement in beam steering and focusing characteristics compared to beam focusing and steering at 24 GHz. The shorter wavelength compared to the spatial variation in plasma density over the radius of the plasma tube, the easier it is to steer and focus antenna beams. These results have been incorporated in a new smart plasma antenna design.

Fundamentals of Meteor Burst Communication

When space dust rushes into the atmosphere, oxygen and nitrogen are ionized by frictional heat. Along the dust flight path, a very long cylindrical plasma tube, 10 meters in diameter and several kilometers long is formed. The long plasma tube is called “meteor burst” and is a good reflector for radio waves in the VHF band. Non-line-of-sight communication performed using this reflector is called “meteor burst communication”. In this chapter, the basics of meteor burst communication and its applications are outlined.

The local technical validation of new plasma tube with a mechanical separator

BackgroundUnsuitable samples are common problem for laboratories. The blood collection tubes need to be validated or verified prior to their being used in the routine laboratory for reducing this situation.ObjectiveWe aim to compare the technical qualifications of routinely used BD Vacutainer® Serum Separator Tubes™ II Advance Plus with BD Vacutainer® Barricor™ LH Plasma Tubes for local technical validation.Materials and methodsApparently healthy 150 voluntary subjects were enrolled in the study. Samples were collected in two separated tubes by a single phlebotomist. Twelve quality indicators were used to compare these two different types of tubes for local technical validation. Differences (%) between them were calculated with the formula proposed by EFLM. In case of any difference of less than 1% for each indicator, the evaluated tube was considered as non-inferior.ResultsIndicators, such as tubes with physical defects, that fail to create vacuum, not properly fitting into the blood collection device, under filling (10%), cracked tubes, tubes exterior surface contaminated with blood, hemolysed specimens, including fibrin strand/mass in the sample, red blood cell adhesion, poor/incomplete barrier formation were found non-inferior in Barricor™ tubes. White particulate matter (WPM) was observed in 24.6% of Barricor™. Therefore, the last indicator (tubes including gel/foreign material/WPM in sample after centrifugation) was found inferior for Barricor™.ConclusionTechnical local validation studies should be encouraged in terms of quality management. It was thought that WPM would not cause any interference in a properly filled tube. In addition to, Barricor™ was also found to be technically acceptable when evaluated through using all other indicators.