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Start Over Topic 02 engineering and technology Topic communication, networking and broadcast technologies Publication Year Range Last 10 years
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1. Constant Envelope Precoding and Non-Orthogonal Multiple Access for Massive MIMO Systems

Author

Tugrul Ozcan, Ayse Melda Yuksel Turgut, TOBB ETU, Faculty of Engineering, Department of Electrical & Electronics Engineering, TOBB ETÜ, Mühendislik Fakültesi, Elektrik ve Elektronik Mühendisliği Bölümü, and Turgut, Ayşe Melda Yüksel

Subjects
Independent and identically distributed random variables, Computer science, signal processing and analysis, engineering profession, 02 engineering and technology, Precoding, Sabit genlikli önkodlama, 5G mobile communication, massive MIMO, 0202 electrical engineering, electronic engineering, information engineering, Electronic engineering, Wireless, MUI, precoding, Rayleigh fading, business.industry, Transmitter, NOMA, dikgen olmayan çoklu erişim, 020206 networking & telecommunications, Communication, networking and broadcast technologies, wireless communication, energy states, CE precoding, Transmission (telecommunications), yoğun çok girdili çok çıktılı sistemler, business, çok kullanıcılı girişimi, tutorials, Communication channel
Abstract

28th Signal Processing and Communications Applications Conference, SIU (2020; Gaziantep, Turkey), Constant Envelope (CE) precoding is a transmission technique, which provides efficient power amplification and can be realised with a single radio frequency (RF) chain at the multi-antenna transmitter. In this paper, we study the multi-user massive MIMO broadcast channel with CE precoding and with non-orthogonal multiple access (NOMA). The motivation for this is to provide different multi-user interferance (MUI) energy levels to different users with different MUI requirements. Wepair users according to their channel conditions and examine the impact of the NOMA on MUI. Simulations for the independent and identically distributed Rayleigh fading channel show that different MUI energy levels is possible with NOMA under CE precoding., Sabit genlikli önkodlama, çok antenli ileticide tek bir radyo frekans zinciri kullanarak, etkili ve uygulanabilir güç yükseltimi sağlayan bir iletim tekniğidir. Bu bildiride, yoğun çok girdili çok çıktılı ve çok kullanıcıya iletim yapılan sistemlerde sabit genlikli önkodlama kullanımı incelenmektedir. Kullanıcılara iletim yapılırken dikgen olmayan çoklu erişim kullanılmaktadır. Bu yöntemle, farklı ihtiyaçlara sahip kullanıcılar için farklı girişim enerjisi seviyeleri sağlamak hedeflenmiştir. Kullanıcıların kanal durumları gözetilerek kullanıcı eşleştirme tekniği kullanılmış ve dikgen olmayan çoklu erişimin kullanıcılarda elde edilen girişim enerjisi üzerindeki etkisi incelenmiştir. Bağımsız ve eş dağılıma sahip Rayleigh sönümlü kanallar üzerinde yapılan benzetim sonuçlarına göre dikgen olmayan çoklu erişim kullanıldığında farklı seviyelerde çok kullanıcılı girişim ene

Published
2020

2. High Dynamic Performance Nonlinear Source Emulator

Author

Khiem Nguyen-Duy, Arnold Knott, and Michael A. E. Andersen

Subjects
Engineering, Power, Energy and Industry Applications, energy resources, Testing, Transportation, Nuclear Engineering, 02 engineering and technology, Terrestrial application, Nonlinear circuits, Renewable energy sources, Electric inverters, Research and development, 0202 electrical engineering, electronic engineering, information engineering, Fuel cells, DC-DC converters, Components, Circuits, Devices and Systems, Renewable energy resources, Communication, Networking and Broadcast Technologies, Engineered Materials, Dielectrics and Plasmas, Current voltage characteristics, General Topics for Engineers, DC-DC power converters, Energy source, Fields, Waves and Electromagnetics, Maximum Power Point Tracking algorithms, High dynamic performance, Computing and Processing, Maximum power principle, Settling time, 020209 energy, Nonlinear circuit, Renewable energy source, Short-circuit currents, Capacitance, Generator (circuit theory), Batteries, Current-voltage characteristics, Downstream converters, Electronic engineering, SDG 7 - Affordable and Clean Energy, Electrical and Electronic Engineering, Aerospace, Clean energy sources, Load modeling, Power converters, Buck converter, business.industry, 020208 electrical & electronic engineering, Control engineering, Maximum power point trackers, Converters, Nonlinear system, Signal Processing and Analysis, Integrated circuit modeling, Filter (video), business
Abstract

As research and development of renewable and clean energy based systems is advancing rapidly, the nonlinear source emulator (NSE) is becoming very essential for testing of maximum power point trackers or downstream converters. Renewable and clean energy sources play important roles in both terrestrial and nonterrestrial applications. However, most existing NSEs have only been concerned with simulating energy sources in terrestrial applications, which may not be fast enough for testing of nonterrestrial applications. In this paper, a high-bandwidth NSE is developed that is able to simulate the behaviors of a typical nonlinear source under different critical conditions that can happen during their operations. The proposed 200-W NSE, which consists of a fourth-order output filter buck converter and a novel nonlinear small-signal reference generator, can quickly react not only to an instantaneous change in the input source but also to a load step between nominal and open circuit. Moreover, all of these operation modes have a very fast settling time of only 10 $\mu$ s, which is hundreds of times faster than that of existing works. This attribute allows for higher speed and a more efficient maximum power point tracking algorithm. The proposed NSE, therefore, offers a superior dynamic performance among devices of the same kind.

Published
2016