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Simulation of OFDM system in Matlab – BER Vs Eb/N0 for OFDM in AWGN channel

To simulate an OFDM system, following design parameters are essential. Lets consider the OFDM system parameters as defined in IEEE 802.11 specifications Given parameters in the spec: N=64; %FFT size or total number of subcarriers (used + unused) 64 Nsd = 48; %Number of data subcarriers 48 Nsp =...
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Introduction to OFDM – orthogonal Frequency division multiplexing – part 4 – Cyclic Prefix

Consider a non-ideal channel h(t)≠δ(t), that causes delay dispersion. Delay dispersion manifests itself as Inter Symbol Interference (ISI)on each subcarrier channel due to pulse overlapping. It will also cause ICC (Inter Carrier Interference ) due to the non-orthogonality of the received signal. Adding cyclic prefix to each OFDM symbol...
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Introduction to OFDM – orthogonal Frequency division multiplexing – part 3

In the previous article, the architecture of an OFDM transmitter was described using sinusoidal components. Generally, an OFDM signal can be represented as s(t) = symbols mapped to chosen constellation (BPSK/QPSK/QAM etc..,) Fn = orthogonal frequency This equation can be thought of as an IFFT process ( Inverse Fast...
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Introduction to OFDM – orthogonal Frequency division multiplexing – part 2

Article moved to new pages The article has been consolidated into these following pages. Please refer these links. If you are looking for Matlab code refer this ebook : Simulation of Digital Communication Systems by Mathuranathan Viswanathan (1) Introduction to OFDM – Orthogonal Frequency Division Multiplexing (2) An OFDM...
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Introduction to OFDM – orthogonal Frequency division multiplexing

In modulations, information is mapped on to changes in frequency, phase or amplitude (or a combination of them) of a carrier signal. Multiplexing deals with allocation/accommodation of users in a given bandwidth (i.e. it deals with allocation of available resource). OFDM is a combination of modulation and multiplexing. In...
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