The energy consumption of the broadcast and wireless communication networks is huge (in the order of several Megawatts for countries like France or Spain). Between 50 and 80 % of this consumption (depending on the type of service) is directly due to the amplification of the signals, because all modern transmission systems (including 4G cellular, digital terrestrial TV) are using multicarrier waveforms, which are characterized by a high Peak to Average Power Ratio (PAPR) leading to a low efficiency of the amplification systems. PAPR reduction techniques can be implemented in order to reduce this dynamic range and thus be able to use the non-linear amplifier at an operating point leading to better energy efficiency. However, non-linear amplification results in in-band distortions measured by the Error Vector Magnitude (EVM) and out-of-band distortions measured by Adjacent Channel Power Ratio (ACPR). Reducing the PAPR of the multicarrier signals in order to improve the efficiency of the power amplifiers while constraining the in-band and out-of-band distortions is then an important research topic with a vast potential for energy savings. With the numerous recent proposals for post-OFDM waveforms such as Filter Bank Multi-Carrier-Offet QAM (FBMC-OQAM), Filtered Multi Tone (FMT), Generalized Frequency Division Multiplexing (GFDM) or Unified Filtered Multi Carrier (UFMC) , which all suffer strong time-domain signal fluctuations as conventional OFDM, the search and proposal of novel PAPR reduction techniques remains a hot topic today.
This research work will be performed within the framework of the FUI “Convergence TV” project, which aims, among other things, at developing innovative solutions for reducing the energy consumption of television transmitters.
The overall objective of this research work is to propose efficient and implementable PAPR reduction techniques for post-OFDM waveforms. The PAPR reduction strategy that is envisaged in this work is the tone reservation (TR) approach as originally introduced by Tellado in . TR-based PAPR are today compatible with two widely deployed broadcast systems, namely DVB-T2 and ATSC 3.0. In addition, efficient TR-based PAPR reduction algorithms have already been proposed by the research team in previous studies . Based on a new kernel definition, these novel algorithms have been shown to outperform many algorithms of the literature and perform very close to the optimal solution given by the QCQP algorithm (Quadratic Constraint Quadratic Problem) while guaranteeing low latency and very reasonable computational complexity [4, 5]. Last but not least, our proposed TR-based solutions, optimized for DVB-T2 as well as ATSC 3.0 have been experimented on a real test-bed and shown to offer around 10% of energy consumption gain, which represents a substantial gain at the scale of a whole network. Hence, our aim is to investigate in which extent and how these proposed algorithms could be adapted to post-OFDM waveforms, in order to anticipate the evolution of multicarrier systems in future generations of broadcast and cellular networks.
The proposed work will be organized according to the following steps:
Advanced and novel efficient solutions will be studied in order to publish in high scientific level journals and communicate in the best international conferences. This work will benefit from the strong experience of IETR concerning multicarrier modulation, PAPR reduction techniques, wireless technologies and associated signal processing in general. During the last 5 years, IETR has been working on those techniques for different applications as future cellular networks and Digital Video Broadcasting in European and National research projects.
KEY WORDS: Post-OFDM multicarrier modulation, PAPR reduction techniques, Signal processing,
CONTACTS: Jean-François Hélard, Matthieu Crussière
INSA/IETR, 20 Avenue des Buttes de Coësmes, 35043, Rennes Cedex
Email: firstname.lastname@example.orgTel : 02 23 23 86 84
email@example.comTel : 02 23 23 85 81
Gerzaguet, R., Bartzoudis, N., Baltar, L.G. et al., "The 5G candidate waveform race: a comparison of complexity and performance", Eurasip Journal on Wireless Communications and Networking (2017) 2017: 13
J. Tellado, “Peak to average power reduction for multicarrier modulation,” Ph.D. dissertation, Stanford University, Sep. 1999.
Ralph Mounzer, "New tone reservation PAPR reduction techniques for multicarrier systems", Ph.D. dissertation, Univ Rennes, INSA Rennes, CNRS, IETR – UMR 6164, 2015.
S. S. K. C. Bulusu, M. Crussière, J. F. Hélard, R. Mounzer, Y. Nasser, O. Rousset, A. Untersee, "Quasi-Optimal Tone Reservation PAPR Reduction Algorithm for Next Generation Broadcasting Systems: A Performance / Complexity / Latency Tradeoff With Testbed Implementation," in IEEE Transactions on Broadcasting.
S. S. K. C. Bulusu, M. Crussière and J. Hélard, "A Low Complexity PAPR Reduction Algorithm for ATSC 3.0 Transmitters," 2018 IEEE International Symposium on Broadband Multimedia Systems and Broadcasting (BMSB), Valencia, 2018, pp. 1-5.
D. Qu, S. Lu, and Y.He. “Sliding Window Tone Reservation Technique for the Peak-to-Average Power Ratio Reduction of FBMC-OQAM Signals”, IEEE Wireless Communications Letters, vol. 1,no. 4, August 2012
M. Laabidi, R. Zayani and R. Bouallegue, "A new tone reservation scheme for PAPR reduction in FBMC/OQAM systems," 2015 International Wireless Communications and Mobile Computing Conference (IWCMC), Dubrovnik, 2015, pp. 862-867.
S. Vangala, A. Sundru, "Overlapped Scaling Tone Reservation method for PAPR Reduction in OFDM/OQAM Systems", Elsevier, 6th International Conference On Advances In Computing & Communications, ICACC 2016, 6-8 September 2016, Cochin, India
S. S. Krishna Chaitanya Bulusu and Hmaied Shaiek and Daniel Roviras , "Reduction of PAPR of FBMC-OQAM systems by dispersive tone reservation technique", IEEE International Symposium on Wireless Communication Systems (ISWCS), 2015
(c) GdR 720 ISIS - CNRS - 2011-2018.