M. Mahdi Assefzadeh

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In this paper, a direct digital-to-impulse transmitter is implemented that radiates impulses with EIRP of 13dBm and a record pulse-width of shorter than 8psec. It is shown that the starting time of the radiated impulses can be locked to the edge of the input trigger with a high timing accuracy. It is demonstrated that two widely spaced chips can generate(More)
In this paper, a lens-less digital-to-impulse radiator is implemented that radiates impulses with EIRP of 10dBm and a record pulse-width of shorter than 9psec using an on-chip differential inverted cone antenna. It is shown that the starting time of the radiated impulses can be locked to the edge of the input trigger with high timing accuracy. A digitally(More)
In this paper, a fully-integrated 4×4 digital-toimpulse radiating array with a programmable delay at each element is reported. Coherent spatial combining from 16 elements is successfully demonstrated. The combined signal from 16 elements achieves a jitter of 230fsec, a pulse width of 14psec, and an EIRP of 17dBm. Each array element is equipped with an 8-bit(More)
This paper presents a broadband THz frequency-comb spectroscopic imager based on a fully-integrated 4×2 picosecond Direct Digital-to-Impulse (D2I) radiating array. By employing a novel trigger-based beamforming architecture, the chip performs coherent spatial combining of broadband radiated pulses achieving an SNR>1 BW of 1.03THz (at the receiver) with a(More)
In this paper, a direct digital-to-impulse architecture is presented that generates impulses with a measured record pulse-width of shorter than 8psec and an output peak power of 6mW. It is shown that the timing of the generated impulses can be locked to the edge of an input trigger with a high timing accuracy. It is also shown that the peak amplitude of the(More)
Abstract: A silicon integrated circuit is reported for radiating picosecond pulses with tunable repetition rate, covering frequencies from 30 GHz to 1.03 THz. This source is used in a gas spectroscopy setup to measure the absorption lines of ammonia and water in the terahertz region. OCIS codes: (120.6200) Spectrometers and spectroscopic instrumentation;(More)
In this paper, multi-order, on-chip transmission line-radial stub ladder networks are designed to perform fundamental and harmonic impedance matching and power combining in a broadband silicon power amplifier. A 16-40GHz, 1W PA with integrated 50Ω output matching and power combining is designed in a 130nm SiGe BiCMOS process. The PA achieves a peak gain of(More)
In this paper, a single-chip impulse antenna array is presented that performs spatial combining of picosecond impulses radiated from 8 elements. A new broadband beamforming architecture is introduced that controls the timing of impulses radiated from each antenna by delaying a trigger signal, with resolution steps of 300fsec. This method eliminates the(More)
Broadband signal generation and radiation is demonstrated based on an oscillator-less Direct Digital-to-Impulse (D2I) picosecond pulse radiator with 153GHz 3dB-BW (252GHz 10dB-BW) centered at 140GHz. The radiated pulse achieves a peak EIRP of 15dBm and peak radiated power of 2.5mW. It is shown that the starting time of the radiated pulse is locked to the(More)