OrthogonalFrequencyDivisionMultiplexing (OFDM) is a multicarrier modulation technique which divides the available spectrum into many carriers. OFDM uses the spectrumefficiently compared to FDMA by spacing the channels much closer together andmaking all carriers orthogonal toone another[1]. In OFDM applications, IFFT/FFT hardware in the transceiver is usually designed jointly to carry out IFFT a...

High Peak-to-Average Power Ratio (PAPR) is one of the major drawback of Orthogonal Frequency Division Multiplexing (OFDM) based systems that can cause intermodulation among the subcarriers due to the nonlinearities of the fiber. The high PAPR increases the complexity of the Analog to Digital (A/D) and Digital to Analog (D/A) converters. In this paper, I present an analysis of Discrete Fourier T...

In this paper, we are going to discuss some fundamental aspects of the implementation of an OFDM modem for wireless indoor applications. One basic component of common OFDM systems is the computation of the DFT. Therefore, some efficient FFT algorithms like the SplitRadix and the Winograd-FFT algorithm have been implemented and their applicability for these modern communication systems has been ...

In this paper, the Bit Error Rate (BER), performance of conventional Discrete Fourier Transform (FFT) OFDM system is compared with Nonconventional Discrete Cosine Transform (DCT)OFDM system in AWGN and Rayleigh fading environment. Performance has been given with conventional mapping schemes like BPSK, QPSK and nonconventional mapping schemes like DQPSK and π/4 DQPSK. Simulation results show tha...

Both light emitting diode (LED) characteristics for illumination and communication simultaneously have made visible communication-orthogonal frequency division multiplexing (VLC-OFDM) a strong competitive to radio (RF). In this juncture, improve signal noise ratio (SNR) coverage contour, the wavelet-OFDM is suggested indoor VLC systems. paper, wavelet VLC-OFDM proposed imaging multiple-input mu...

Orthogonal Frequency Division Multiplexing (OFDM) is a multicarrier transmission technique that divides the available spectrum into multiple carriers in which each one is being modulated by a low rate data stream. OFDM is similar to FDMA in that the multiple user access is achieved by subdividing the available bandwidth into multiple channels band, which is then allocated to users. So, OFDM use...

End-to-end learning systems are conceived for Orthogonal Frequency Division Multiplexing (OFDM)-aided optical Intensity Modulation paired with Direct Detection (IM/DD) communications relying on the Autoencoder (AE) architecture in deep learning. We first propose an AE-aided Layered ACO-OFDM (LACO-OFDM) scheme, termed as LACONet, exploiting increased bandwidth efficiency of LACO-OFDM. LACONet em...

We present areaand power-efficient pipeline 128and 128/64-point fast Fourier transform (FFT) processors for 8x8 multipleinput multiple-output orthogonal frequency multiplexing (MIMO-OFDM) systems based on the specification framework of IEEE 802.11ac WLANs. Our new FFT processors use mixed-radix multipath delay commutator (MRMDC) architecture from the point of view of low complexity and high mem...

We propose and experimentally demonstrate a new scheme to reduce the energy consumption of optical network units (ONUs) in orthogonal frequency division multiplexing passive optical networks (OFDM PONs) by using time-domain interleaved OFDM (TI-OFDM) technique. In a conventional OFDM PON, each ONU has to process the complete downstream broadcast OFDM signal with a high sampling rate and a large...

Orthogonal frequency division multiplexing (OFDM) is a popular modulation technique that is widely utilized in many wireless communication systems. Traditional OFDM based on fast Fourier transform (FFT) involves the use of a rectangular window; consequently, high side lobes are created. Hence, OFDM based on discrete multiwavelet critical sampling transform (DMWTCS) is proposed in this paper. DM...