Sharif Digital Repository

In this paper, a closed-form two-dimensional reconstruction technique for hybrid frequency and mechanical scanning millimeter-wave (MMW) imaging systems is proposed. Although being commercially implemented in many imaging systems as a low-cost real-time solution, the results of frequency scanning systems have been reconstructed numerically or have been reported as the captured raw data with no clear details. Furthermore, this paper proposes a new framework to utilize the captured data of different frequencies for three-dimensional (3D) reconstruction based on novel proposed closed-form relations. The hybrid frequency and mechanical scanning structure, together with the proposed... 

In this paper a new method for measuring phase noise of microwave oscillators based on delay line frequency discriminator is proposed. Elimination of phase shifter is the major advantage of this technique over the traditional delay line technique. By using this new technique, manual or electronic tuning of phase shifter to reach phase quadrature at the phase detector input ports is not needed anymore. A 90-degree hybrid is used in this technique and another path including a phase detector and LNA is added. Finally by using a dual channel FFT analyzer and performing some processing over the sampled data of the two channels, the phase noise of the oscillator will be extracted. A setup based on...