In this paper, orthogonal frequency-division multiplexing–code-division multiplexing (OFDM-CDM) is presented and investigated as alternative to conventional OFDM for high rate data transmission. An additional multipath diversity gain can be obtained with OFDM-CDM by spreading each data symbol in frequency and time. The optimum reliability information for the Viterbi decoder is derived for OFDM-...

1. Mrs.Veena M.B. Dr.M.N.ShanmukhaSwamy,“Performance analysis of DWT based OFDM over FFT based OFDM and implementing on FPGA” International Journal of VLSI design & Communication Systems (VLSICS) Vol.2, No.3, September 2011. 2. Deepak Gupta, Vipin B Vats, Kamal K. Garg, “Performance Analysis of DFT-OFDM, DCT-OFDM, and DWT-OFDM Systems in AWGN Channel” International Conference on Wireless and Mo...

The Orthogonal Frequency Division Multiplexed (OFDM) system introduced here, termed Interference Suppressing OFDM (IS-OFDM), has the capabilities of suppressing narrow-band interference in wide band wireless applications. The IS-OFDM encodes each transmitted symbol in all frequency bins. Each frequency bin will then “contain” all transmitted symbols which are distinguished and separated from ea...

N -continuous OFDM is a modulation technique that has a lower sidelobe than the original OFDM as a result of the continuous connection with its higher-order derivatives between the OFDM symbols. However, N -continuous OFDM has a high symbol error rate. In the present paper, we improve N -continuous OFDM without increasing the symbol error rate by using a selected mapping technique.

Orthogonal frequency division multiplexing (OFDM) is particularly divided to three varieties. Cyclic prefix OFDM, zero padding OFDM, and time domain synchronous OFDM. Compared to CP OFDM, TDS-OFDM has higher spectral efficiency and faster synchronization. This paper reviewed however efficiently uses the compressive sensing (CS) theory to resolve those problems. During this paper, a noise cancel...

This paper presents a new method to improve on block spread OFDM by exploiting time diversity to ensure that the blocks are independent and uncorrelated. Simulation results have shown significant improvement over conventional OFDM and Block Spread OFDM. Disciplines Physical Sciences and Mathematics Publication Details Raad, I. S. & Huang, X. (2006). Exploiting time diversity to improve block sp...

In this paper, we introduce a novel merger of antenna arrays with scanning beam patterns, and Orthogonal Frequency Division Multiplexing (OFDM) systems. Controlled time varying phase shifts are applied to the antenna array elements mounted at the base station with beam patterns directed toward the desired user. This creates a small beam pattern movement called Beam Pattern Scanning (BPS). In ri...

Abstract— Orthogonal frequency division multiplexing (OFDM) is an important technique to support high speed transmission of broadband traffic in wireless networks, especially broadband wireless local area networks (LANs). Based on OFDM, a new multiple access scheme, called OFDM-TDMA with subcarrier allocation (OFDMTDMA/SA), is introduced in this paper. It provides more flexibility in resource a...

In this paper we address the issue of OFDM and PCC-OFDM systems impaired by phase noise (PN). PCC-OFDM is a variation of OFDM in which data is mapped onto adjacent subcarrier pairs. As a result intercarrier interference (ICI) in adjacent subcarriers is cancelled. Phase noise in OFDM causes both ICI and common phase error (CPE). PCC-OFDM reduces the ICI component, but the CPE is unchanged. Theor...