Sidelobe Modulation Scrambling Transmitter Using Fourier Rotman Lens

rotman lens

آرایه فازی به منظور هدایت بیم در راستایی خاص نیازمند شبکه تغذیه ویژه ای می باشد. رتمن لنز به عنوان یکی از این ساختارهای تغذیه با قابلیت تحریک چند بیم در زوایای متفاوت در یک زمان، استفاده گسترده ای پیدا کرده است. در این پژوهش مهم ترین عوامل موثر بر پهنای باند این شبکه در ساختار مایکرواستریپ، که شبکه تطبیق امپدانس، رفتار انتشاری موج در بخش صفحات موازی و خطای فاز خطوط انتقال می باشند، بررسی شده و ...

Rotman Lens Antenna in Microstrip Configuration

Single Coil PILS Imaging Using Phase-Scrambling Fourier Transform Technique

Introduction Parallel image reconstruction using local sensitivities (PILS)[1] accelerate MR scan time by using multiple receiver coil in parallel scan time. We propose a novel imaging technique which is based on the PILS, but uses only a single set of signals. The signal obtained in the phase-scrambling Fourier Transform imaging (PSFT)[2] can be transformed into the signal described by the Fre...

Fading-resistant modulation using several transmitter antennas

This paper proposes a bandwidth-eecient fading-resistant transmission scheme which implements transmitter diversity using L antennas at the base station. When the antennas are spaced suuciently far apart, the transmission from each antenna undergoes a diierent degree of fading. These transmissions are coordinated to mitigate the eeects of Rayleigh fading and the mobile receiver can recover the ...

Transmitter authentication using hierarchical modulation in dynamic spectrum sharing

One of the critical challenges in dynamic spectrum sharing (DSS) is identifying non-conforming transmitters that violate spectrum access rules prescribed by a spectrum regulatory authority. One approach for facilitating identification of the transmitters in DSS is to require every transmitter to embed an uniquely-identifiable authentication signal in its waveform at the PHY-layer. In most of th...