Orthogonal Frequency Division Multiplexing (OFDM) has become the popular modulation technique in high speed wireless communications. One of the main disadvantages of Orthogonal Frequency Division multiplexing (OFDM) is its high Peak-to-Average Power Ratio (PAPR), which significantly reduces the efficiency of the High Power Amplifier (HPA). Due to the simplest way for PAPR reduction, clipping te...

In this paper, we discuss the performance of the orthogonal frequency division multiplexing (OFDM) wireless communication systems using the binary phase shift keying (BPSK) modulation over Rayleigh fading channel implementing the generalized receiver (GR) constructed in accordance with the generalized approach to signal processing in noise. We compare OFDM-BPSK wireless communication systems ba...

Recent advances in wireless communications have made use of MC-CDMA and OFDM techniques to allow for high data rate transmission. Rapid time variations of the wireless communication channel have a effect on the performance of multicarrier modulation. In this paper, we emphasis the Doppler spread and Computes its effect on the bit error rate (BER) for multicarrier code division multiple access (...

Multiple Input Multiple Output-Orthogonal Frequency Division Multiplexing (MIMO-OFDM) systems play a vital role in the channel estimation. The wireless channel suffers from impairments like fading and interference. Technologies that achieved above requirements are Multiple Input Multiple Output (MIMO) and Orthogonal Frequency Division Multiplexing (OFDM). Channel impairments must be mitigated a...

Abstract— In this paper, we propose the use of verticalBell Labs layered space-time (V-BLAST) detection for orthogonal frequency division multiplexing code division multiplexing (OFDM-CDM) systems. Considering the properties of the VBLAST detection as well as the frequency diversity from CDM, we propose a new CDM transform matrix to improve the performance of V-BLAST detection of OFDM-CDM signa...

The use of frequency-domain interleaving on a frame-byframe basis for orthogonal frequency division multiplexing (OFDM) combined with time division multiplexing (OFDM/TDM) is presented. In conventional OFDM, FDE is not designed to exploit the channel frequencyselectivity and consequently, the frequency diversity gain cannot be obtained. To further improve the bit error rate (BER) performance of...

Multiple input multiple output-orthogonal frequency division multiplexing-code division multiplexing (MIMO-OFDM-CDM) techniques are considered to improve the link reliability/spectral efficiency of very high data rate communication systems. In particular, lattice-reduction-aided receivers are proposed for MIMO-OFDM-CDM systems. Simulation results show that the proposed receivers significantly o...

In this paper, an OFDM-CDM (orthogonal frequency division multiplexing code division multiplexing) system with adaptive symbol mapping is presented. This combination enables a robust transmission with flexible error protection and data rate adaptation for parallel data streams by exploiting additional diversity due to CDM. Performance results are presented for fading channels where OFDMCDM with...

In the present work, we have combined Orthogonal Space-Frequency Block Coding (OSFBC) and Spatial Multiplexing (SM) in one transmission scheme for Orthogonal Frequency Division Multiplexing (OFDM) systems. In the combined transmission scheme, both spatial diversity and multiplexing benefits are possible to achieve. Simple Alamouti coding as the S-F coding across spatial multiplexing branches an...

Orthogonal Frequency Division Multiplexing with Offset Quadrature Amplitude Modulation (OFDM / OQAM) is a multicarrier modulation scheme that can be considered as an alternative to the conventional Orthogonal Frequency Division Multiplexing (OFDM) with Cyclic Prefix (CP) for transmission over multipath fading channels. In this paper, we investigate the combination of the OFDM/OQAM with Alamouti...