3,954 research outputs found
Waveform Design for 5G and Beyond
5G is envisioned to improve major key performance indicators (KPIs), such as
peak data rate, spectral efficiency, power consumption, complexity, connection
density, latency, and mobility. This chapter aims to provide a complete picture
of the ongoing 5G waveform discussions and overviews the major candidates. It
provides a brief description of the waveform and reveals the 5G use cases and
waveform design requirements. The chapter presents the main features of cyclic
prefix-orthogonal frequency-division multiplexing (CP-OFDM) that is deployed in
4G LTE systems. CP-OFDM is the baseline of the 5G waveform discussions since
the performance of a new waveform is usually compared with it. The chapter
examines the essential characteristics of the major waveform candidates along
with the related advantages and disadvantages. It summarizes and compares the
key features of different waveforms.Comment: 22 pages, 21 figures, 2 tables; accepted version (The URL for the
final version:
https://onlinelibrary.wiley.com/doi/abs/10.1002/9781119333142.ch2
Multi-service systems: an enabler of flexible 5G air-interface
Multi-service system is an enabler to flexibly support
diverse communication requirements for the next generation
wireless communications. In such a system, multiple types of
services co-exist in one baseband system with each service having
its optimal frame structure and low out of band emission (OoBE)
waveforms operating on the service frequency band to reduce the
inter-service-band-interference (ISvcBI). In this article, a
framework for multi-service system is established and the
challenges and possible solutions are studied. The multi-service
system implementation in both time and frequency domain is
discussed. Two representative subband filtered multicarrier
(SFMC) waveforms: filtered orthogonal frequency division
multiplexing (F-OFDM) and universal filtered multi-carrier
(UFMC) are considered in this article. Specifically, the design
methodology, criteria, orthogonality conditions and prospective
application scenarios in the context of 5G are discussed. We
consider both single-rate (SR) and multi-rate (MR) signal
processing methods. Compared with the SR system, the MR
system has significantly reduced computational complexity at the
expense of performance loss due to inter-subband-interference
(ISubBI) in MR systems. The ISvcBI and ISubBI in MR systems
are investigated with proposed low-complexity interference
cancelation algorithms to enable the multi-service operation in
low interference level conditions
A Link Quality Model for Generalised Frequency Division Multiplexing
5G systems aim to achieve extremely high data rates, low end-to-end latency
and ultra-low power consumption. Recently, there has been considerable interest
in the design of 5G physical layer waveforms. One important candidate is
Generalised Frequency Division Multiplexing (GFDM). In order to evaluate its
performance and features, system-level studies should be undertaken in a range
of scenarios. These studies, however, require highly complex computations if
they are performed using bit-level simulators. In this paper, the Mutual
Information (MI) based link quality model (PHY abstraction), which has been
regularly used to implement system-level studies for Orthogonal Frequency
Division Multiplexing (OFDM), is applied to GFDM. The performance of the GFDM
waveform using this model and the bit-level simulation performance is measured
using different channel types. Moreover, a system-level study for a GFDM based
LTE-A system in a realistic scenario, using both a bit-level simulator and this
abstraction model, has been studied and compared. The results reveal the
accuracy of this model using realistic channel data. Based on these results,
the PHY abstraction technique can be applied to evaluate the performance of
GFDM based systems in an effective manner with low complexity. The maximum
difference in the Packet Error Rate (PER) and throughput results in the
abstraction case compared to bit-level simulation does not exceed 4% whilst
offering a simulation time saving reduction of around 62,000 times.Comment: 5 pages, 8 figures, accepted in VTC- spring 201
Generalized Fast-Convolution-based Filtered-OFDM: Techniques and Application to 5G New Radio
This paper proposes a generalized model and methods for fast-convolution
(FC)-based waveform generation and processing with specific applications to
fifth generation new radio (5G-NR). Following the progress of 5G-NR
standardization in 3rd generation partnership project (3GPP), the main focus is
on subband-filtered cyclic prefix (CP) orthogonal frequency-division
multiplexing (OFDM) processing with specific emphasis on spectrally well
localized transmitter processing. Subband filtering is able to suppress the
interference leakage between adjacent subbands, thus supporting different
numerologies for so-called bandwidth parts as well as asynchronous multiple
access. The proposed generalized FC scheme effectively combines overlapped
block processing with time- and frequency-domain windowing to provide highly
selective subband filtering with very low intrinsic interference level. Jointly
optimized multi-window designs with different allocation sizes and design
parameters are compared in terms of interference levels and implementation
complexity. The proposed methods are shown to clearly outperform the existing
state-of-the-art windowing and filtering-based methods.Comment: To appear in IEEE Transactions on Signal Processin
- …