Multi-Carrier Spread-Spectrum

l 1 Khaled Fazel , Gerhard P. Fettweis lGerman Aerospace Research Establishment (DLR) Institute for Communications Technology 0-82234 Oberpfaffenhofen, Germany lDresden University of Technology Department of Electrical Engineering 0-01062 Dresden, Germany To operate future generation multimedia communications systems high data rate transmission needs to be guaranteed with a high quality of service. For instance, the third generation cellular mobile systems should offer a high data rate up to 2 Mbitls for video, audio, speech and data transmission [1]. In addition, the important challenge for these cellular systems will be the choice of an appropriate multiple access scheme. These trends motivated many researchers to look for multiple access systems that offer high spectral efficiency. The technique of spread spectrum originating from the military applications may allow partly to fulfill the above requirements. Advantages of spread spectrum technique are broadly known: High immunity against multipath distortion, no need for frequency planning, high flexibility, easier variable rate transmission etc. [1-2]. A multiple access scheme based on direct sequence spread spectrum, known as direct sequence code division multiple access (DS-CDMA) relies on spreading the data stream using an assigned spreading code for each user in the time domain. The capability of minimising multiple access interference (MAl) is given by the cross­ correlation properties of spreading codes. In the case of multipath propagation the capability of distinguishing one component from others in the composite received signal is offered by the auto-correlation properties of the spreading codes [2]. Front Matter....Pages i-xvii Front Matter....Pages 1-1 Multi-Carrier Spread Spectrum: An Attractive Special Case of General Multiuser/Multisubchannel Transmission Methods....Pages 3-12 Overview of the results about multitone CDMA detection....Pages 13-21 Comparison of Multiple Access Schemes for an OFDM Downlink System....Pages 23-30 Link/System Level Performance of an OFDM/CDMA Downlink Configuration....Pages 31-38 Front Matter....Pages 39-39 Performance Analysis of a New Multi-Code and Multi-Carrier Hybrid Transmission Scheme for Future Broadband Mobile Communication Systems....Pages 41-48 A Spread-Spectrum Multi-Carrier Multiple-Access System for Mobile Communications....Pages 49-56 Orthogonal Frequency-Division Multiple Access with Frequency Hopping and Diversity....Pages 57-68 M-ARY Orthogonal Modulation for MC-CDMA Systems in Indoor Wireless Radio Networks....Pages 69-76 Comparison of Wlan Multicarrier DS-SS Physical Layer Configurations in Measured Indoor Environment....Pages 77-86 Front Matter....Pages 87-87 Multi-Carrier CDMA Using Convolutional Coding and Interference Cancellation over Fading Channels....Pages 89-96 An Approach for a Multi-Carrier Spread Spectrum System with Rake Receiver....Pages 97-104 Multi-Carrier Modulated Orthogonal Code-Division Multiple Access (MCM-OCDMA)....Pages 105-110 Interleaved FDMA — A New Spread-Spectrum Multiple-Access Scheme....Pages 111-118 Aspects on Wideband Multi-Carrier Communication....Pages 119-126 Equalization and Coding for Extended MC-CDMA Over Time and Frequency Selective Channels....Pages 127-134 Detection Method for MC-CDMA Based on A Recurrent Neural Network Structure....Pages 135-142 Front Matter....Pages 143-143 Sensitivity of OFDM/CDMA to Carrier Phase Jitter....Pages 145-152 Time Domain Uplink Channel Estimation in Multicarrier-CDMA Mobile Radio System Concepts....Pages 153-160 Subspace-Based Joint Time-Delay and Frequency-Shift Estimation in Multitone-Code Division Multiple Access (MT-CDMA) Systems....Pages 161-167 Pilot-Symbol-Aided Channel Estimation in Time and Frequency....Pages 169-178 Front Matter....Pages 143-143 A Family of Extended Gaussian Functions with a Nearly Optimal Localization Property....Pages 179-186 On the Duality of Multi-Carrier Spread Spectrum and Single-Carrier Transmission....Pages 187-194 Mismatched Multi Carrier Complementary Spread Spectrum Radar and Sonar Systems....Pages 195-200 Front Matter....Pages 201-201 An OFDM/SFH-CDMA Transmission Scheme for the Uplink....Pages 203-210 Uplink spectral efficiency of multicarrier joint detection code division multiple access based cellular radio systems....Pages 211-218 Simulation of a DSSS/MCM System in a Doppler Spread Channel....Pages 219-226 On the Performance of Asynchronous Multi-Carrier CDMA....Pages 227-234 Performance Comparison Between OC-FD/DS-CDMA and MC-CDMA Over Rayleigh Fading Channels....Pages 235-242 To operate future generation multimedia communications systems high data rate transmission needs to be guaranteed with a high quality of service. For instance, the third generation cellular mobile systems should offer a high data rate up to 2 Mbit/s for video, audio, speech and data transmission. The important challenge for these cellular systems will be the choice of an appropriate multiple access scheme. The advantages of the spread spectrum technique are: High immunity against multipath distortion, no need for frequency planning, high flexibility and easier variable rate transmission etc. On the other hand, the technique of multi-carrier transmission has recently been receiving wide interest for high data rate applications. The advantages of multi-carrier transmission are the robustness in the case of frequency selective fading channels, in particular the reduced signal processing complexity by equalization in the frequency domain, and in the capability of narrow-band interference rejection. The advantages and success of multi-carrier (MC) modulation and the spread spectrum (SS) technique has led to the combination of MCM with SS, known as multi-carrier spread-spectrum (MC-SS) for cellular systems. This combination, benefits from the advantages of both schemes: Higher flexibility, higher spectral efficiency, simpler detection techniques, narrow band interference rejection capability, etc. Multicarrier-Spread-Spectrum comprises a collection of papers which collectively provide a state-of-the-art overview of this emerging multiple access scheme. It will be a valuable reference for all researchers and practitioners working on the area of wireless communications and networking