Concepts for possible use of high temperature superconductors in millimeter/submillimeter wave cavities, mode convertors and waveguides are described. Reduction of the ohmic loss in the cavities could remove a major constraint on the power produced by high frequency gyrotrons. Significant benefits could be obtained without the need for ultra high values of cavity Q. Improved mode convertor perf...

In x-ray imaging detectors, the signal generated in a detector element is proportional to the number of secondary carriers (such as optical photons or electronhole pairs) generated in the x-ray convertor. Furthermore, the location and statistics of secondary carriers are directly related to the absorbed x-ray energy. Even under monochromatic exposure conditions, there will be a distribution of ...

Efficiency of Orthogonal Frequency-Division Multiplexing (OFDM) system is improved by reducing the power consumed by its transmitter and also by improving the spectral efficiency. Power usage is reduced by reducing the PAPR of OFDM system and spectral efficiency is improved by Adaptive modulation and coding schemes (AMC). In OFDM system, transmission signals can have high peak values in the tim...