Massive MIMO and Waveform Design for 5th Generation Wireless Communication Systems

This article reviews existing related work and identifies the main challenges in the key 5G area at the intersection of waveform design and large-scale multiple antenna systems, also known as Massive MIMO. The property of self-equalization is introduced for Filter Bank Multicarrier (FBMC)-based Massive MIMO, which can reduce the number of subcarriers required by the system. It is also shown that the blind channel tracking property of FBMC can be used to address pilot contamination -- one of the main limiting factors of Massive MIMO systems. Our findings shed light into and motivate for an entirely new research line towards a better understanding of waveform design with emphasis on FBMC-based Massive MIMO networks.Comment: 6 pages, 2 figures, 1st International Conference on 5G for Ubiquitous Connectivit

Design and Linearization of Energy Efficiency Power Amplifier in Nonlinear OFDM Transmitter for LTE-5G Applications. Simulation and measurements of energy efficiency power amplifier in the presence of nonlinear OFDM transmitter system and digital predistortion based on Hammerstein-Wiener method

This research work has made an effort to understand a novel line of radio frequency power amplifiers (RFPAs) that address initiatives for efficiency enhancement and linearity compensation to harmonize the fifth generation (5G) campaign. The objective is to enhance the performance of an orthogonal frequency division multiplexing-long term evolution (OFDM-LTE) transmitter by reducing the nonlinear distortion of the RFPA. The first part of this work explores the design and implementation of 15.5 W class AB RF power amplifier, adopting a balanced technique to stimulate efficiency enhancement and redeeming exhibition of excessive power in the transmitter. Consequently, this work goes beyond improving efficiency over a linear RF power amplifier design; in which a comprehensive investigation on the fundamental and harmonic components of class F RF power amplifier using a load-pull approach to realise an optimum load impedance and the matching network is presented. The frequency bandwidth for both amplifiers was allocated to operate in the 2.620-2.690 GHz of mobile LTE applications. The second part explores the development of the behavioural model for the class AB power amplifier. A particular novel, Hammerstein-Wiener based model is proposed to describe the dynamic nonlinear behaviour of the power amplifier. The RF power amplifier nonlinear distortion is approximated using a new linear parameter approximation approach. The first and second-order Hammerstein-Wiener using the Normalised Least Mean Square Error (NLMSE) algorithm is used with the aim of easing the complexity of filtering process during linear memory cancellation. Moreover, an enhanced adaptive Wiener model is proposed to explore the nonlinear memory effect in the system. The proposed approach is able to balance between convergence speed and high-level accuracy when compared with behavioural modelling algorithms that are more complex in computation. Finally, the adaptive predistorter technique is implemented and verified in the OFDM transceiver test-bed. The results were compared against the computed one from MATLAB simulation for OFDM and 5G modulation transmitters. The results have confirmed the reliability of the model and the effectiveness of the proposed predistorter.Fundacão para a Ciência e a Tecnologia, Portugal, under European Union’s Horizon 2020 research and innovation programme ... grant agreement H2020-MSCA-ITN- 2016 SECRET-722424 I also acknowledge the role of the National Space Research and Development Agency (NASRDA) Sokoto State Government Petroleum Technology Trust Fund (PTDF

Analysis of Multi Carrier Modulation Techniques for 5G Physical Layer Communications Estimation of KPI

The more enchanting Multicarrier Communication (MCM) techniques like Fifth Generation (5G), Long Term Evolution (LTE) and Fourth Generation (4G) are the enhancing techniques that contribute the progress of wireless communication systems. The most effective way to save resources in 5G is to make efficient use of all existing discontinuous spectrums, which maximizes Spectrum Efficiency (SE). A valid comparison of many 5G MCM techniques is made in this work, namely Universal Filter Multi Carrier (UFMC), Filter Bank Multi Carrier (FBMC) and Orthogonal Frequency Division Modulation (OFDM). Various Key Performance Indicators (KPI) such as Bit Error Ratio (BER), Signal to Interference Ratio (SIR), Power Spectral Density (PSD) and ratio between Peak Power and Average Power, Throughput, and Spectral Efficiency (SE) are evaluated and compared under various realistic channels. UFMC Modulation technique is compatible with existing channel estimation and detection techniques and further improves SE. The SE of FBMC has been improved by 2% with Hermite filter when compared to PHYSDAS, RRC prototype filters. It has been observed that FBMC offered better SIR, Throughput, also a complex design of filter reduced BER and PAPR

30 GHz Path Loss Modeling and Performance Evaluation for Noncoherent M-ary Frequency Shift Keying in the 30 GHz Band

A candidate millimeter-wave (mmWave) frequency band and modulation scheme that could fit to many present and future applications has been presented in this work. As is being explored by industry, we also suggest the 30 GHz band as a candidate carrier frequency and non-coherent frequency shift keying (NC-FSK) as a potential modulation scheme for future communication applications. The primary applications are aimed at 5th generation (5G) cellular type systems. Propagation measurements were conducted for outdoor and indoor environments using directional horn antennas for both co-polarized and cross-polarized antenna configurations to model the path loss for our candidate band. The measurements were conducted in typical line-of-sight (LOS) and non-LOS (NLOS) environments in a large building on the University of South Carolina campus, specifically at Swearingen Engineering Center. Several propagation path loss (PL) models are presented based upon this collected data. We can use these PL models in link budgets for estimating transmit power, antenna gains, receiver characteristics (e.g., noise figure), and link distances. The measurements also contribute to the body of knowledge on wireless channel propagation path loss for bands near 30 GHz. Another measurement campaign was also conducted at the USC campus to measure a unique and complicated vegetation attenuation that may be considered a large challenge to mmWave systems. Radio wave attenuation and depolarization effects through several broadleaf evergreen shrubs at 31 GHz are reported, based upon measurements. To obtain a comparative reference for this mmWave attenuation, another measurement was also conducted at 5 GHz. From these measurements, we analyzed the proportional relationships between the attenuation and the shrub density (related to species), depth, and measurement geometry. Three different shrub species with different densities and depths, and for different measurement geometries, were employed. Results are in terms of measured specific attenuations at 31 GHz—the attenuation in dB/m. These will also be useful for link budget design, and outdoor and outdoor-indoor models for future mmWave communication. For our 5G modulation scheme candidate, we evaluate its performance at 31 GHz via an empirical 3-D mmWave channel simulator: the NYUSIM channel model. As with all digital communication systems, performance is measured in terms of error ratios, and we evaluate the bit error rate (BER) performance of NC-FSK for different symbol rates over a variety of wireless mmWave channels. The NC-FSK scheme is known to be energy efficient for large alphabet size, and this is one of its virtues. Another is that since it is a form of FM, nonlinear amplification (far less costly than linear amplification) can be used. The performance evaluations enable us to present enhancements and trade-offs that can be done to improve the system performance by adjustment of the design parameters, i.e., modulation alphabet size and symbol rate, which together determine bandwidth (BW)