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Simulation and analysis of SC-FDMA based cellular systems for LTE uplink transmission

DOI:10.1007/s10586-017-1257-x
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G. B. S. R. Naidu
G. B. S. R. Naidu
G. B. S. R. Naidu
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V. Malleswara Rao
V. Malleswara Rao
V. Malleswara Rao
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Abstract and Figures

SC-FDMA is the major enabling technique for today’s wireless communication. It is mainly adopted in the uplink of LTE and LTE-A cellular systems. OFDMA is another key technique employed in downlink of current wireless systems. These techniques offers benefits like increase in throughput, bandwidth efficiency, data rate and less interference. Apart from these advantages it suffers from the problem of high PAPR over a journey 4G to 5G. Although, there is extensive work done in this aspect, still there is a gap to further reduce the PAPR and improve the efficiency of next generation wireless networks. In this paper, the performance evaluation of SC-FDMA and OFDMA is carried out in LTE physical layer using various probabilistic schemes (PTS and SLM), adaptive modulation shift keying (Mary-PSK and Mary-QAM) by considering the parameters like PAPR. The study of various research papers tells that the PTS has a better PAPR reduction than SLM and when companding is, performed (Formula presented.)-law yields good results compared to A-law. However, the proposed companded-PTS obtains low PAPR than conventional methods like (Formula presented.)-law companding, PTS and SLM.
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Cluster Comput (2019) 22:S10947–S10954
https://doi.org/10.1007/s10586-017-1257-x
Simulation and analysis of SC-FDMA based cellular systems
for LTE uplink transmission
G. B. S. R. Naidu1·V. Malleswara Rao2
Received: 19 August 2017 / Revised: 5 October 2017 / Accepted: 7 October 2017 / Published online: 7 November 2017
© Springer Science+Business Media, LLC 2017
Abstract SC-FDMA is the major enabling technique for
today’s wireless communication. It is mainly adopted in
the uplink of LTE and LTE-A cellular systems. OFDMA is
another key technique employed in downlink of current wire-
less systems. These techniques offers benefits like increase in
throughput, bandwidth efficiency, data rate and less interfer-
ence. Apart from these advantages it suffers from the problem
of high PAPR over a journey 4G to 5G. Although, there
is extensive work done in this aspect, still there is a gap
to further reduce the PAPR and improve the efficiency of
next generation wireless networks. In this paper, the perfor-
mance evaluation of SC-FDMA and OFDMA is carried out
in LTE physical layer using various probabilistic schemes
(PTS and SLM), adaptive modulation shift keying (Mary-
PSK and Mary-QAM) by considering the parameters like
PAPR. The study of various research papers tells that the
PTS has a better PAPR reduction than SLM and when com-
panding is, performed μ-law yields good results compared to
A-law. However, the proposed companded-PTS obtains low
PAPR than conventional methods like μ-law companding,
PTS and SLM.
Keywords OFDMA ·SC-FDMA ·SLM ·PTS. PAPR ·
BER
BG. B. S. R. Naidu
mail2gbsrphdk@gmail.com
1Department of ECE, GMR Institute of Technology,
Rajam-srikakulam, Andhra Pradesh, India
2Department of ECE, GITAM Institute of Technology, GITAM
University, Visakhapatnam, Andhra Pradesh, India
1 Introduction
Orthogonal frequency-division multiple access (OFDMA)
has its unique and emphasizing place in the modern world
technologies. It works on offering faster and more reliable
communications services. Orthogonal frequency-division
multiple access is a worthy preference for its scope in
establishing reliable better data rate communications in
wireless environments. Orthogonal frequency-division mul-
tiple access is developed from the initial procedures of
frequency-division multiplexing (FDM). The problem with
the conventional FDM units is that they cannot effectively
make use of the offered bandwidth, as it has no spectral over-
lap among the adjacent carriers. This unwanted data is later
aggravated with the addition of the guard bands rather than
transmitting completely separate signals. The main idea of
OFDMA is to subpart the bits of a high-data rate transmission
into multiple low data rate bit streams using a serial-to-
parallel converter. Thus obtained lower-data rate bits are
transmitted with various carrier frequencies after modula-
tion [1]. The orthogonal nature of those multiple carriers
(sub-carriers) and the spectral overlap sets the OFDM to dif-
fer from its earlier techniques. Latest DSP techniques such
as fast Fourier transform (FFT) have made more realizable
utilization of OFDM [1,2]. There are various parameters like
those that Bit error rate, complexity, Peak to average power
ratio (PAPR), detection of SI bits and a few others are to
be keenly considered for evaluation. Out of them, PAPR is
to be optimized well for effective communication [2]. The
relationship between single carrier-FDMA and OFDMA for
the transmission of a signal occupying the overall bandwidth
[3,4].
There is a similarity between OFDMA and SC-FDMA for
the transmission of independent signals from various termi-
nals to one base station. Figure 1show that OFDMA and
123
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... But they require additional complexity and cost to reduce the power efficiency. The partial transmit sequence and selected mapping techniques aligned with companding functions are about the methods to minimize PAPR [3,4]. These practices need excess bandwidth and also broadcast the side information and complicated. ...
... The complementary CDF of the PAPR then shows the probability that the PAPR, which is a random quantity, exceeds a particular threshold [2,4]. ...
... But conceding the complexity for localized SC-FDMA with companding function, the modulation symbols are clustered into blocks, each covering with N symbols and followed N-point FFT. Then, the subcarrier mapping and M-point IFFT actions are performed [2,4]. The FFT signal can be treated as ...
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