UDC 621.396.2
Estimation
of interference effects on pilot subcarriers of OFDM-signal of the IEEE 802.11n
K. D.
Titov, O. N. Zavalishina
Voronezh
State University, University sq. 1, Voronezh 394018, Russia
The paper is received
on December 3, 2019
Abstract. In this work the influence of interference on the wireless data
transmission channel is analyzed on the example of the widely used standard
IEEE 802.11n, based on the use of OFDM technology. Features of the standard are
investigated, consisting in the type, number and frequency position of the
signal subcarriers, the mode of data transmission and the data packets formed
at the same time, as well as algorithms for signal synchronization in the time
and frequency domains. To assess the noise immunity of the IEEE 802.11n
standard itself, the structure of the bitstream formed during the transmission
of information over the wireless channel at the channel and physical levels,
without taking into account the upper levels (without reference to the type of
information transmitted) of the OSI network model was studied. Using the
simulation in MATLAB Simulink, the dependence of the bit error probability on
the noise-to-signal ratio when exposed to pilot and information subcarriers is
obtained. The influence of distortion of pilot subcarriers on the quality of
functioning of the wireless data transmission channel is estimated. It is
established that the distortion of pilot subcarriers leads to the failure of
rough and exact time and frequency synchronizations, as well as the impossibility
of estimating and correcting the channel parameters. In particular, this leads
to the inability to determine the beginning of the OFDM symbol, frequency and
time mismatch, transmitted and received signals, as well as frequency offset
with the accuracy to the distance between the subcarriers.
Key words: noise
immunity, correction capability, wireless link, bit error rate, synchronization.
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For citation:
Titov K.D., Zavalishina
O.N. Estimation
of interference effects on pilot subcarriers of OFDM-signal of the IEEE 802.11n. Zhurnal Radioelektroniki - Journal of
Radio Electronics. 2019. No. 12. Available
at http://jre.cplire.ru/jre/dec19/6/text.pdf
DOI 10.30898/1684-1719.2019.12.6