OFDM has been proven to be a viable technique to overcome multipath fading in wireless channels. While OFDM systems convert a multipath fading channel into a series of equivalent flat fading channels they lack the inherent diversity available in multipath channels. Theoretically an uncoded OFDM system needs a simple receiver due to ISI free channel, but their performance deteriorates in the pre...

Relay network was introduced to realize high-data rate transmission and high capacity with limited transmit power. However, channel state information (CSI) is needed due to the requirement from coherent data detection and the self-data removal at terminals in the two-way relay networks (TWRN). Traditional linear probing techniques are able to acquire the accurate CSI by using enough training se...

An adaptive multipath decorrelating multiuser receiver is considered for application in Rayleigh fading multipath channels with significant Doppler spread. Coherent diversity combining is performed using adaptively obtained channel estimates in a manner that minimizes the impact of estimation errors on data detection. The bit-error rate of the receiver is evaluated analytically, showing depende...

This paper presents a new transmission scheme of M-ary biorthogonal pulse position modulation (BPPM) in ultra wideband systems. The proposed scheme incorporates position-wise parity information to improve the probability of symbol detection over multipath channels. A linear filter-based channel modification is also introduced to mitigate multipath degradation and maximize the probability of sym...

This paper presents a new theory of multipath shape factors that greatly simplifies the description of small-scale fading statistics of a wireless receiver. A method is presented for reducing a multipath channel with arbitrary spatial complexity to three shape factors that have simple intuitive geometrical interpretations. Furthermore, these shape factors are shown to describe the statistics of...

This dissertation is concerned with the propagation of ultrawideband (UWB) electromagnetic impulses in complex multipath environments. In the first part the distortion of a UWB signal as it propagates through frequency selective materials is examined. The potential degree of distortion is investigated through experimental measurements, then the effect of that distortion on UWB communication and...

To support realtime multimedia communication, future mobile communications will require a high-bit-rate transmission system with high utilization of the frequency spectrum in very rich multipath channels [1]. Systems capable of fulfilling this requirement, with features such as orthogonal frequency division multiplexing (OFDM) [2], [3] and multiple-input multiple-output (MIMO) [4]–[7], have bee...

Aalto University, P.O. Box 11000, FI-00076 Aalto www.aalto.fi Author Zhong Zheng Name of the doctoral dissertation Statistical Analysis of Cascaded Multipath Fading Channels Publisher School of Electrical Engineering Unit Department of Communications and Networking Series Aalto University publication series DOCTORAL DISSERTATIONS 209/2015 Field of research Communications Engineering Manuscript ...

In 2002 the German Aerospace Centre (DLR) performed a measurement campaign of the land mobile multipath channel. From this data a channel model was derived that is synthesising the measured channel impulse response. It allows the realistic simulation of the multipath channel by approximating every single reflection. This model includes time variant reflectors approaching and receding in depende...

The conventional MIMO systems have a capability of enhancing channel capacity by exploiting multipath environment [1]. Recently, a novel scheme which utilizes MIMO system in near-field region has proposed [2]. In the near-field MIMO system, channel capacity is able to be improved without a multipath, because spherical wave is considered as a superposition of plane waves. It is expected that the...