Fade depth prediction on airborne line-of-sight communication links is considered in this paper. There is no specific model for this scenario at the moment. The two ray multipath model adapted to a realistic scenario of hilly or mountainous terrain was used to account for flight and terrain geometry, and antenna parameters. Surprisingly, it was found that (i) in many practically important cases...

The through–line calibration family uses measurements of a through connection and an inserted line to determine the propagation constant of the line. This is typically used with measurements of a reflect standard to characterize fixturing errors. Subsequently, the S-parameters of a device under test are de-embedded. Measurement uncertainties occur at frequencies where the length of the line sta...

Absmucr-Direct sequence code division multiple access commun-kations is a promising approach to cellular mobile communications , whkh operates in an environment characterized by mul-tipath Rician fading. In this paper, the CDMA network is assumed to share common spectrum with a narrowband microwave user. Because of the presence of the narrowband waveform, an interference suppression filter at e...

An atmosphere of rain offers a dispersi e medium for the propagation of radio signals abo e 10 GHz. The effect of dispersion, in terms of differential attenuation and phase dispersion, is insignificant for narrowband signals. Signals modulated with ery short pulses can ha e a wide bandwidth o er which dispersion will be appreciable, causing significant signal distortion. The propagation of puls...

A thin cylindrical ceramic sample is placed in a single mode microwave applicator in such a way that the electric eld strength is allowed to vary along its axis. The sample can either be a single rod or two rods butted together. We present a simple mathematical model which describes the microwave heating process. It is built on the assumption that the Biot number of the material is small, and t...

We present a numerical study of an array-based microwave beamforming approach for non-invasive hyperthermia treatment of pediatric brain tumors. The transmit beamformer is designed to achieve localized heating-that is, to achieve constructive interference and selective absorption of the transmitted electromagnetic waves at the desired focus location in the brain while achieving destructive inte...

RF power output has been a major planning aspect for engineers since the start of radio transmission. Undoubtedly important, RF Power level is only one of many factors that determine a successful wireless network. To effectively evaluate and differentiate between various microwave systems and link performance, operators should be able to examine several key aspects of RF power output. Propagati...

We present new kind of microwave phase shifters (MPS) based on dispersion of PbS colloidal quantum dots (QDs) in commercially available photoresist SU8 after a ligand exchange process. Ridge PbS-SU8 waveguides are implemented by integration of the nanocomposite in a silicon platform. When these waveguides are pumped at wavelengths below the band-gap of the PbS QDs, a phase shift in an optically...

Propagation of electromagnetic (EM) waves in radio frequency (RF) and microwave systems is described mathematically by Maxwell’s equations with corresponding boundary conditions. Dielectric properties of lossless and lossy materials influence EM field distribution. For a better understanding of the physical processes associated with various RF and microwave devices, it is necessary to know the ...

Forward Error correcting Codes (FEC) is a technique used for controlling errors in data transmission over unreliable or noisy communication channels. This scheme is overhead in many wireless communication systems, even though they have enhanced data rates for the GSM evolution (EDGE), because, worldwide interoperability for microwave access (WiMAX) and long term evolution (LTE) have adopted low...