Recently, frequency-domain equalization (FDE) has been attracting much attention as a way to improve single-carrier (SC) signal transmission in a frequency-selective wireless channel. Since the SC signal spectrum is spread over the entire signal bandwidth, FDE can take advantage of channel frequency-selectivity and achieve the frequency diversity gain. SC with FDE is a promising wireless signal...

In a high mobility environment, single-carrier (SC) space-frequency block coding (STBC) diversity achieves better bit error rate (BER) performance than SC space-time block coding (STBC) diversity. However, in a strong frequency-selective fading channel, the BER performance degrades due to the orthogonality distortion of SFBC codeword. In this paper, we propose a frequency-domain equalization (c...

In this work we investigate the possibilities of combining diversity techniques with a Single Carrier System with Frequency Domain Equalization (SC/FDE), as future transmission concepts will also be judged by their possibilities to be combined with multiple antennas. Concepts of multiple antennas allow either a significant performance gain through diversity or significant higher capacity based ...

The performance of single-carrier (SC) transmission in a frequency-selective fading channel degrades due to a severe inter-symbol interference (ISI). Using frequency-domain equalization (FDE) based on the minimum mean square error (MMSE) criterion can improve the bit error rate (BER) performance of SC transmission. However, the residual ISI after FDE limits the performance improvement. In this ...

Abstract In DS-CDMA high speed wireless signal transmissions, the transmission performance degrades due to frequency selective fading. The use of frequency-domain equalization (FDE) can significantly improve the transmission performance. However, the local average received signal power slowly varies due to distance-dependent path loss and shadowing loss according to the movement of a mobile use...

In this Letter, a frequency-domain pre-rake transmission is presented for a direct sequence spread spectrum with time division duplex (DSSS/TDD) system under a frequency-selective fading channel. The mathematical relationship between frequency-domain and time-domain pre-rake transmissions is discussed. It is confirmed by the computer simulation that, similar to the time-domain pre-rake transmis...

CDMA and MIMO-CDMA systems using RAKE receivers are heavily limited by selfand multiple-accessinterference. Linear equalization is a means to remove this interference, however it is often not practical due to the enormous complexity, especially in the MIMO case. This paper presents an approach to greatly reduce the complexity of linear MIMO equalizers. It discusses the complexity reduction of t...

Orthogonal multicode direct sequence code division multiple access (DS-CDMA) has a flexibility in offering various data rate services. However, in a frequency-selective fading channel, the bit error rate (BER) performance is severely degraded since othogonality among spreading codes is partially lost. In this paper, we apply frequency-domain equalization and antenna diversity combining, used in...

Frequency-domain equalization (FDE) can take advantage of the frequency-selectivity of the channel to improve the transmission performance in a frequency selective fading channel. To further improve the transmission performance, the transmit diversity technique can be used. Cyclic delay transmit diversity (CDTD) can strengthen the frequencyselectivity while space-time transmit diversity (STTD) ...

There has been growing interest in coherent optical orthogonal frequencydivision multiplexing (CO-OFDM). We aim to present the case that the time for CO-OFDM has come, in terms of the demand from today’s ever-advancing optical networks and the availability of its underlying technologies. We first lay out the signal processing aspect for CO-OFDM and then show a 2 2 multiple-input–multiple-output...