In learning undergraduate controls, one of the most abstract and confusing concepts is that of phase margin (PM). One frustration is the difficulty in conceptualizing what physical process could produce the pure phase shift referred to in the definition of PM. Another frustration occurs when simple second-order formulas given for PM do not work in practice. Finally, when resonances occur, there...

We analytically study received waveform asymmetries induced by chromatic dispersion (CD) for signed CD monitoring in differential quadrature phase-shift keying (DQPSK) systems and show that the asymmetries are results of differential detection and the ±π/4 phase shifters used in conventional DQPSK receivers. The theoretical insights developed help explain various published results on signed CD ...

Millimeter-wave phase shifters are important components for a wide scope of applications. An analog-type phase shifter for W-band has been designed, analyzed, fabricated, and measured. The phase shifter consists of a reconfigurable highimpedance surface (HIS) controlled by micro-electromechanical system (MEMS) varactors and placed adjacent to a silicon dielectric rod waveguide. The analog-type ...

A new type of distributed analog phase shifter is presented that utilizes the coplanar strip transmission line topology. This transmission line has several benefits for phase shifter design, resulting in decreased physical dimensions and potentially lower losses. A prototype was constructed using thin-film barium strontium titante (BST) varactor technology. The design achieved a 49◦/dB figure o...

With the congestion of the sub-6GHz spectrum, the interest in massive multiple-input multiple-output (MIMO) systems operating on millimeter wave spectrum grows. In order to reduce the power consumption of such massive MIMO systems, hybrid analog/digital transceivers and application of low-resolution digital-to-analog/analog-to-digital converters have been recently proposed. In this work, we inv...