Publications by Yuanyan Su | EPFL Graph Search

Compact Irregular Conformal Phased Array: High-Gain Wide-Scan Onboard System for Enhancing UAV Communication

This paper proposes a compact non-canonical non-uniform conformal phased array antenna (NNCPAA) attached to an irregular UAV surface to overcome the space and aerodynamic constraints for high-gain, wide-scan applications. The NNCPAA is parametrically deter ...

2024

LEMAC: LTF-EPFL Miniature Atomic Clock Demonstrator Performance Evaluation

Anja Skrivervik, Maddalena Violetti, Yuanyan Su

We report on the performance evaluation of the LEMAC miniature atomic clock, based on the optical-microwave Double-Resonance (DR) scheme, implementing a micro-fabricated Rb vapor cell held inside a custom-designed micro-loop-gap microwave resonator (μ-LGR) ...

Institute of Electrical and Electronics Engineers Inc.2024

Micro-Loop-Gap Microwave Resonator Development for the LEMAC LTF-EPFL Miniature Atomic Clock

Anja Skrivervik, Maddalena Violetti, Yuanyan Su

This paper discusses several evolved micro-loop-gap microwave resonator designs for chip-scale atomic clock applications. Two different schemes have been investigated to develop the LEMAC (LTF-EPFL Miniature Atomic Clock) based on the optical-microwave dou ...

Institute of Electrical and Electronics Engineers Inc.2024

Code for project entitled "study on conformal antennas, proof of concept prototype for a UAV"

Anja Skrivervik, Yuanyan Su

This code is used for developing the project entitled “Study on conformal antennas, proof of concept prototype for a UAV”, from the aspects of theory, design, and implementation. This code aims to speed up the investigation of an arbitrary phased array ant ...

Zenodo2024

Microwave cavities for dual resonance atomic clocks

Anja Skrivervik, Yuanyan Su

Dual resonance Rubidium atomic clock requires a microwave resonator tuned to the frequency of the hyperfine transition of the Rubidium 87 isotope. The vapor cell containing the Rubidium atoms is placed within this resonator. In order to achieve a good cloc ...

Institute of Electrical and Electronics Engineers Inc.2023

Toward Metantennas: Metamaterial-Based Antennas for Wireless Communications

Yuanyan Su

Antennas have historically been the most common electromagnetic (EM) technology for wireless communication systems. Antenna as hardware is entirely dependent on the EM properties of the materials used, mostly related to the permittivity and permeability. I ...

Ieee-Inst Electrical Electronics Engineers Inc2023

Mode Suppression and Homogeneous Field Bandwidth Enhancement of a Tuning-Free Micro-Loop-Gap Resonator Using FR4 for Chip-Scale Rubidium Clock

Yuanyan Su

We propose strategies for the design of a tuning-free micro-loop-gap resonator (mu-LGR) that provides high magnetic field homogeneity of the TE011-like mode over a broad bandwidth with a high field orientation factor (FOF). This broadband feature allows it ...

Institute of Electrical and Electronics Engineers2023

Microwave Metalens Antennas

Yuanyan Su, Teng Li

Recently, there has been growing interest in the use of metamaterial (MTM)-based lenses, also known as metalenses, as innovative antenna technology. Increasingly widespread applications of metalenses in modern microwave communication and sensing systems ha ...

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC2023

A Wide-Frequency-Tuning Micro-Loop-Gap Resonator for Miniature Rubidium Vapor-Cell Atomic Frequency Standards

Anja Skrivervik, Yuanyan Su

To miniaturize the double-resonance (DR) rubidium (Rb) vapor-cell atomic clocks, a new type of micro-loop-gap microwave resonator (mu-LGR) is proposed for TE011-like mode where the magnetic field inside the cavity is homogeneous and oriented along its long ...

Institute of Electrical and Electronics Engineers2023

mu POP Clock: A Microcell Atomic Clock Based on a Double-Resonance Ramsey Scheme

Anja Skrivervik, Maddalena Violetti, Yuanyan Su

We demonstrate and study a microcell microwave atomic clock based on optical-microwave double resonance (DR) interrogation operated in a pulsed Ramsey scheme, called the mu POP clock, based on a microfabricated Rb vapor cell and a micro-loop-gap microwave ...

American Physical Society (APS)2022

LEMAC: LTF-EPFL Miniature Atomic Clock

Anja Skrivervik, Maddalena Violetti, Yuanyan Su

We present the latest development of our in-house miniature atomic clock (LEMAC). The clock scheme is based on the continuous wave (CW) optical-microwave double resonance (DR) interrogation. Significant efforts have been put in a newly designed miniature m ...

IEEE2022

Experimental Determination of Relaxation Rates in a Ramsey-mode Rubidium Cell Atomic Clock

Anja Skrivervik, Maddalena Violetti, Yuanyan Su

We describe a method to measure the relaxation rates in Rubidium (Rb) Pulsed Optically Pumped (POP) vapor cell frequency standards. By means of repeated spectroscopy measurements with varying Ramsey time, we show how to extract multiple estimations of the ...

IEEE2022

Ramsey Spectroscopy in a Micro-Fabricated Rb Vapor Cell for Miniature Atomic Clocks

Anja Skrivervik, Yuanyan Su

We present a prospective experimental study on double-resonance Ramsey spectroscopy in a micro fabricated Rb vapor cell, in view of future miniature atomic clocks with improved stability performance. Ramsey signals with a narrow central fringe width of 1.5 ...

IEEE2021

Characterization of Microwave Substrates for High Accuracy and Long-Term Stability Using Full-Wave Microstrip Ring Resonator Method

Anja Skrivervik, Miroslav Veljovic, Yuanyan Su

An accurate material characterization method for microwave printed-circuit-board substrates is proposed by combining the microwave ring resonator method with iterative full-wave simulations. A detailed error analysis is performed quantitatively to compensa ...

IEEE2021

A Compact Transformation Optics-based Luneburg Lens Antenna using Curved Reactive Impedance Surface

Anja Skrivervik, Yuanyan Su

This paper is to investigate the pattern distortion that happens in the extremely low incidence angle for a flat TM-polarized half Luneburg lens antenna (HLLA) by using a purely reactive impedance surface (RIS). For the scenario of a radar mounted on an un ...

IEEE2021