This document discusses spectrally efficient frequency division multiplexing (SEFDM) and its advantages over orthogonal frequency division multiplexing (OFDM). SEFDM allows for closely spaced subcarriers to conserve bandwidth compared to OFDM. The objective is to estimate the bit error rate (BER) performance of SEFDM and compare it to OFDM. Detection techniques for SEFDM include sphere decoding, truncated singular value decomposition, and other linear decoders. A literature review presented research on SEFDM and methods to alleviate the complexity of maximum likelihood detection.

1. Academic Writing
Subjective assignment II
BY
P.ABIRAMI
Application number :
62f3ec87f34111e9a24d8d678f1ab741
SASTRA Deemed to be University
Thanjavur
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2. ACKNOWLEDGEMENT
I would like to acknowledge ALL MY STAFF
FOR THEIR constant support and help.
I pay my gratitude to Academic Writing
course which taught me how to write a research
article and how to publish an article without
plagiarism and also about the digital writing.
I thank my parents and almighty for their
blessings and grace
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3. PRESENTATION
SPECTRALLY EFFICIENT
FREQUENCY DIVISION
MULTIPLEXING
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4. OBJECTIVE
• To estimate the BER performance of SEFDM and
compare it with OFDM.
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5. Introduction
• OFDM:
• It constraints subcarriers to exist in fixed positions to
maintain orthogonality
• In terms of spectral efficiency – OFDM delivers the highest
efficiency for an orthogonal system
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• SEFDM:
• One of the non-orthogonal techniques
• Closely spaced subcarriers to conserve the BW
• Lower bandwidth utilisation

7. Literature Survey
YEAR TITLE AUTHOR INFERENCE
2014 Spectrally Efficient FDM:
Spectrum Saving
Technique for 5G
Tongyang Xu and
Izzat Darwazeh
Optimal detection
method is used.
2009 Spectrally Efficient FDM Signals:
Bandwidth Gain
at the Expense of Receiver
Complexity
Ioannis Kanaras,
Arsenia Chorti,
Miguel R.D.
Rodrigues and Izzat
Darwazeh
An alternative
detection
mechanism based
on the Generalized
Sphere Decoding
(GSD) algorithm.

8. Literature Survey
s.no TITLE AUTHOR INFERENCE
2009 To alleviate the complexity of ML
detection alternative detection
methods including linear detectors
and genetic algorithms (GA)
based detectors are used.
Ioannis Kanaras,
Arsenia Chorti,
Miguel Rodrigues
and Izzat Darwazeh
A Quasi-Optimal
Detection Algorithm
Is used.
2003 A Spectrally Efficient Frequency
Division
Multiplexing Based
Communications System
M. R. D. Rodrigues
and I.Darwazeh
To alleviate the
complexity of ML
detection
alternative detection
methods including
linear detectors and
genetic algorithms
(GA) based
detectors are used.

9. BCF
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10. Spectra
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Fig. OFDM signal Fig. SEFDM signal

11. Output

12. Detection Techniques
• Sphere decoder
• Truncated singular value decomposition
• Other linear decoders
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13. REFERENCES
• A Spectrally Efficient Frequency Division Multiplexing Based
Communications System M. R. D. Rodrigues and I. Darwazeh Laboratory
for Communications Engineering Telecommunications Research Group
Dept. Engineering, University of Cambridge Dept. E&EE, University
College London.
• BER Performance of SEFDM Signals in LTE Fading Channels Sergei
Gorbunov and Andrey Rashich Radio and telecommunication systems
department Peter the Great St. Petersburg Polytechnic University St.
Petersburg, Russia serggv91@gmail.com, rashich@cee.spbstu.ru
• Spectrally Efficient FDM Signals: Bandwidth Gain at the Expense of
Receiver Complexity Ioannis Kanaras1, Arsenia Chorti1, Miguel R.D.
Rodrigues and Izzat Darwazeh IEEE Dep., University College London,
London WC1E 7JE, UK, i.kanaras, a.chorti, Institute of Telecomunication
,University of Porto, 4169 - 007 Porto, Portugal, mrodrigues@dcc.fc.up.pt
• B. Hassibi H. Vikalo "On the sphere-decoding algorithm expected
complexity" IEEE transactions on signal processing vol. 53 no. 8 pp. 2806-
2818 .

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Thank You