1 research outputs found
Intersymbol and Intercarrier Interference in OFDM Systems: Unified Formulation and Analysis
A unified matrix formulation is presented for the analysis of intersymbol and
intercarrier interference in orthogonal frequency-division multiplexing (OFDM)
systems. The proposed formulation relies on six parameters and allows studying
various schemes, including those with windowing in the transmitter and/or in
the receiver (called windowed OFDM systems), which may add cyclic suffix and/or
cyclic prefix (CP), besides the conventional CP-OFDM. The proposed framework
encompasses seven different OFDM systems. It considers the overlap-and-add
procedure performed in the transmitter of windowed OFDM systems, being jointly
formulated with the channel convolution. The intersymbol and intercarrier
interference, caused when the order of the channel impulse response is higher
than the number of CP samples, is characterized. A new equivalent channel
matrix that is useful for calculating both the received signal and the
interference power is defined and characterized. Unlike previous works, this
new channel matrix has no restrictions on the length of the channel impulse
response, which means that the study is not constrained to the particular case
of two or three data blocks interfering in the received signal. Theoretical
expressions for the powers of three different kinds of interference are
derived. These expressions allow calculating the
signal-to-interference-plus-noise ratio, useful for computing the data rate of
each OFDM system. The proposed formulation is applied to realistic examples,
showing its effectiveness through comparisons based on numerical performance
assessments of the considered OFDM systems