228 research outputs found
Performance Analysis of FBMC and CP-OFDM in the Presence of Phase Noise
Multi-Carrier (MC) modulation schemes like Or-
thogonal Frequency Division Multiplexing (OFDM) are highly
sensitive to Phase Noise (PN). In the case of air interfaces
operating in higher frequencies, e.g. the range between 6 and
100 GHz frequently called millimeter wave (mmWave), the PN
generated by the local oscillators is even more accentuated.
Alternative MC systems are being considered for future mmWave
wireless communications. In this contribution, we analytically
derive expressions for an upper bound for the interference power
generated by the PN in OFDM, DFT-Spread-OFDM and Filter
Bank Multi-Carrier (FBMC). Then, we evaluate the performance
degradation due to that imperfection in terms of coded and
uncoded BER
Dual-Polarization OFDM-OQAM Wireless Communication System
In this paper we describe the overall idea and results of a recently proposed
radio access technique based on filter bank multicarrier (FBMC) communication
system using two orthogonal polarizations: dual-polarization FBMC (DP-FBMC).
Using this system we can alleviate the intrinsic interference problem in FBMC
systems. This enables use of all the multicarrier techniques used in
cyclic-prefix orthogonal frequency-division multiplexing (CP-OFDM) systems for
channel equalization, multiple-input/multiple-output (MIMO) processing, etc.,
without using the extra processing required for conventional FBMC. DP-FBMC also
provides other interesting advantages over CP-OFDM and FBMC such as more
robustness in multipath fading channels, and more robustness to receiver
carrier frequency offset (CFO) and timing offset (TO). For DP-FBMC we propose
three different structures based on different multiplexing techniques in time,
frequency, and polarization. We will show that one of these structures has
exactly the same system complexity and equipment as conventional FBMC. In our
simulation results DP-FBMC has better bit error ratio (BER) performance in
dispersive channels. Based on these results, DP-FBMC has potential as a
promising candidate for future wireless communication systems.Comment: 1.This paper is accepted to be published in IEEE Vehicular Technology
Conference (VTC) FALL 2018. 2.In this new submitted version authors have
revised the paper based on the VTC FALL reviewers comments. Therefore some
typos have fixed and some results have change
FBMC system: an insight into doubly dispersive channel impact
It has been claimed that filter bank multicarrier (FBMC) systems suffer from negligible performance loss caused by moderate dispersive channels in the absence of guard time protection between symbols. However, a theoretical and systematic explanation/analysis for the statement is missing in the literature to date. In this paper, based on one-tap minimum mean square error (MMSE) and zero-forcing (ZF) channel equalizations, the impact of doubly dispersive channel on the performance of FBMC systems is analyzed in terms of mean square error of received symbols. Based on this analytical framework, we prove that the circular convolution property between symbols and the corresponding channel coefficients in the frequency domain holds loosely with a set of inaccuracies. To facilitate analysis, we first model the FBMC system in a vector/matrix form and derive the estimated symbols as a sum of desired signal, noise, intersymbol interference (ISI), intercarrier interference (ICI), interblock interference (IBI), and estimation bias in the MMSE equalizer. Those terms are derived one-by-one and expressed as a function of channel parameters. The numerical results reveal that under harsh channel conditions, e.g., with large Doppler spread or channel delay spread, the FBMC system performance may be severely deteriorated and error floor will occur
MIMO signal processing in offset-QAM based filter bank multicarrier systems
Next-generation communication systems have to comply with very strict requirements for increased flexibility in heterogeneous environments, high spectral efficiency, and agility of carrier aggregation. This fact motivates research in advanced multicarrier modulation (MCM) schemes, such as filter bank-based multicarrier (FBMC) modulation. This paper focuses on the offset quadrature amplitude modulation (OQAM)-based FBMC variant, known as FBMC/OQAM, which presents outstanding spectral efficiency and confinement in a number of channels and applications. Its special nature, however, generates a number of new signal processing challenges that are not present in other MCM schemes, notably, in orthogonal-frequency-division multiplexing (OFDM). In multiple-input multiple-output (MIMO) architectures, which are expected to play a primary role in future communication systems, these challenges are intensified, creating new interesting research problems and calling for new ideas and methods that are adapted to the particularities of the MIMO-FBMC/OQAM system. The goal of this paper is to focus on these signal processing problems and provide a concise yet comprehensive overview of the recent advances in this area. Open problems and associated directions for future research are also discussed.Peer ReviewedPostprint (author's final draft
Filter Bank Multicarrier for Massive MIMO
This paper introduces filter bank multicarrier (FBMC) as a potential
candidate in the application of massive MIMO communication. It also points out
the advantages of FBMC over OFDM (orthogonal frequency division multiplexing)
in the application of massive MIMO. The absence of cyclic prefix in FBMC
increases the bandwidth efficiency. In addition, FBMC allows carrier
aggregation straightforwardly. Self-equalization, a property of FBMC in massive
MIMO that is introduced in this paper, has the impact of reducing (i)
complexity; (ii) sensitivity to carrier frequency offset (CFO); (iii)
peak-to-average power ratio (PAPR); (iv) system latency; and (v) increasing
bandwidth efficiency. The numerical results that corroborate these claims are
presented.Comment: 7 pages, 6 figure
A Comparison of CP-OFDM, PCC-OFDM and UFMC for 5G Uplink Communications
Polynomial-cancellation-coded orthogonal frequency division multiplexing
(PCC-OFDM) is a form of OFDM that has waveforms which are very well localized
in both the time and frequency domains and so it is ideally suited for use in
the 5G network. This paper analyzes the performance of PCC-OFDM in the uplink
of a multiuser system using orthogonal frequency division multiple access
(OFDMA) and compares it with conventional cyclic prefix OFDM (CP-OFDM), and
universal filtered multicarrier (UFMC). PCC-OFDM is shown to be much less
sensitive than either CP-OFDM or UFMC to time and frequency offsets. For a
given constellation size, PCC-OFDM in additive white Gaussian noise (AWGN)
requires 3dB lower signal-to-noise ratio (SNR) for a given bit-error-rate, and
the SNR advantage of PCC-OFDM increases rapidly when there are timing and/or
frequency offsets. For PCC-OFDM no frequency guard band is required between
different OFDMA users. PCC-OFDM is completely compatible with CP-OFDM and adds
negligible complexity and latency, as it uses a simple mapping of data onto
pairs of subcarriers at the transmitter, and a simple weighting-and-adding of
pairs of subcarriers at the receiver. The weighting and adding step, which has
been omitted in some of the literature, is shown to contribute substantially to
the SNR advantage of PCC-OFDM. A disadvantage of PCC-OFDM (without overlapping)
is the potential reduction in spectral efficiency because subcarriers are
modulated in pairs, but this reduction is more than regained because no guard
band or cyclic prefix is required and because, for a given channel, larger
constellations can be used
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