# EXTENDING OFDM SYMBOLS TO REDUCE POWER CONSUMPTION

### André B. J. Kokkeler, Gerard J. M. Smit

#### Abstract

Existing communication standards have limited capabilities to adapt to low SNR environments or to exploit low data rate requirements in a power efficient way. Existing techniques like e.g. control coding do not reduce the computational load when reducing data rates. In this paper, we introduce differential Extended Symbol OFDM (differential ES-OFDM) which is based on the transmission of symbols that are extended in time. This way it can operate at low SNR. Using differential BPSK modulation, approximately 2.1 dB SNR improvement per doubling of the symbol length (halving the bitrate) is obtained. The sensitivity to frequency offsets of differential ES-OFDM is basically independent of symbol extension. Extending symbols reduces the computational load on the radio modem within the transmitter which is essential to reduce overall power consumption. The differential ES-OFDMreceiver architecture also offers opportunities to reduce power consumption.

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#### Paper Citation

#### in Harvard Style

B. J. Kokkeler A. and J. M. Smit G. (2012). **EXTENDING OFDM SYMBOLS TO REDUCE POWER CONSUMPTION** . In *Proceedings of the 1st International Conference on Smart Grids and Green IT Systems - Volume 1: SMARTGREENS,* ISBN 978-989-8565-09-9, pages 257-262. DOI: 10.5220/0003950002570262

#### in Bibtex Style

@conference{smartgreens12,

author={André B. J. Kokkeler and Gerard J. M. Smit},

title={EXTENDING OFDM SYMBOLS TO REDUCE POWER CONSUMPTION},

booktitle={Proceedings of the 1st International Conference on Smart Grids and Green IT Systems - Volume 1: SMARTGREENS,},

year={2012},

pages={257-262},

publisher={SciTePress},

organization={INSTICC},

doi={10.5220/0003950002570262},

isbn={978-989-8565-09-9},

}

#### in EndNote Style

TY - CONF

JO - Proceedings of the 1st International Conference on Smart Grids and Green IT Systems - Volume 1: SMARTGREENS,

TI - EXTENDING OFDM SYMBOLS TO REDUCE POWER CONSUMPTION

SN - 978-989-8565-09-9

AU - B. J. Kokkeler A.

AU - J. M. Smit G.

PY - 2012

SP - 257

EP - 262

DO - 10.5220/0003950002570262