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Use of multiple antennas at both ends of wireless links is the result of the natural progression of more than four decades of evolution of adaptive antenna technology. Recent advances have demonstrated that multiple- input-multiple-output (MIMO) wireless systems can achieve impressive increases in o ...

At the macroscopic level of system layout, the most important issue is path loss. In the older mobile radio systems that are limited by receiver noise, path loss determines SNR and the maximum coverage area. In cellular systems, where the limiting factor is cochannel interference, path loss determin ...

By definition, the term “mobile-radio communications” describes any radio communication link between two terminals of which one or both are in motion or halted at unspecified locations and of which one may actually be a fixed terminal such as a base station. This definition applies to both mobile- ...

The last decade proved to be hugely successful for the mobile communications industry, characterised by continued and rapid growth in demand, spurred on by new technological advances and innovative marketing techniques. Of course, when we refer to mobile commu- nications, we tend to implicitly refer ...

In general there are three different techniques for performance evaluation of systems and networks: mathematical analysis, measurements, and computer simulation. All these techniques have their strength and weaknesses. In the literature there are plenty of discussions about when to use which techniq ...

Multi-carrier modulation‚ Orthogonal Frequency Division Multi- plexing (OFDM) particularly‚ has been successfully applied to a wide variety of digital communications applications over the past several years. Although OFDM has been chosen as the physical layer standard for a diversity of important ...

Since the principle of multi-carrier code division multiple access (MC-CDMA) was simultaneously proposed by Khaled Fazel et al. and Nathan Yee et al. at the IEEE International Symposium on Personal, Indoor and Mobile Radio Communications (PIMRC) in the year 1993, multi-carrier spread spectrum (MC-SS ...

At recent major international conferences on wireless communications, there have been several sessions on beyond third generation (3G) or fourth generation(4G)mobilecommunicationssystems,wheremodulation/demod- ulation and multiplexing/multiple access schemes related to multicarrier techniques have d ...

Many wireless communications channels consist of multiple signal paths from the transmitter to receiver. This multiplicity of paths leads to a phenomenon known as multipath fading. The multiple paths are caused by the presence of objects in the physical environment that, through the mechanisms of pr ...

The family of recent wireless standards included the optional employment of MIMO tyechniques. This was motivated by the observation according to the classic Shannon-Hartley law the achiev- able channel capacity increases logarithmically with the transmit power. By contrast, the MIMO capacity increas ...