Yahya M. Tousi

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We will introduce a design of analog-to-digital converters (ADCs) based on digital delay lines. Instead of voltage comparators, they convert the input voltage into a digital code by delay lines and are mainly built on digital blocks. This makes it compatible with process scaling. Two structures are proposed, and tradeoffs in the design are discussed. The(More)
We introduce a novel frequency tuning method for high-power terahertz sources in CMOS. In this technique, multiple core oscillators are coupled to generate, combine, and deliver their harmonic power to the output node without using varactors. By exploiting the theory of nonlinear dynamics, we control the coupling between the cores to set their phase shift(More)
Sub-mm-Wave and terahertz frequencies have many applications such as medical imaging, spectroscopy and communication systems. CMOS signal generation at this frequency range is a major challenge due to the limited cut-off frequency of transistors and their low breakdown voltage. A recent work has demonstrated generation of high power at a fixed frequency in(More)
This work introduces a 2-D phased array architecture that is suitable for high power radiation at mm-Wave and Terahertz frequencies. We address the challenge of signal generation above the cut-off frequency of transistors by presenting a radiationmethod based on the collective performance of a large number of synchronized sources. As theory shows, both(More)
We present a solid-state tunable terahertz source that exploits the theory of coupled oscillators to simultaneously achieve high output power and frequency tuning. Our proposed structure effectively generates and combines high power harmonics from multiple synchronized solid-state oscillators in a loop configuration. We study the dynamics of the system,(More)
A delay-line-based analog-to-digital converter for high-speed applications is introduced. The ADC converts the sampled input voltage to a delay that controls the propagation velocity of a digital pulse. The output digital code is generated based on the propagation length of the pulse in a fixed time window. The effects of quantization noise, jitter, and(More)
In this paper, we propose a 2-D electrical interferometer as a means of high-speed data conversion. The structure is based on wave propagation in 2-D LC lattices. We will discuss the principle behind this technique, which exploits wave propagation and medium manipulation in order to take advantage of different interference patterns. This method of(More)
We present a passive digital-to-phase converter with sub-degree phase precision for phased array frontends. The phase tuning approach is based on manipulating the electromagnetic properties of an artificially constructed transmission line. By simultaneously controlling dispersion, characteristic impedance, and loss across the structure, the phase shifter(More)
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