Implementable Wireless Access for B3G Networks - III: Complexity Reducing Transceiver Structures

This article presents a comprehensive overview of some of the research conducted within Mobile VCE’s Core Wireless Access Research Programme,1 a key focus of which has naturally been on MIMO transceivers. The series of articles offers a coherent view of how the work was structured and comprises a compilation of material that has been presented in detail elsewhere (see references within the article). In this article MIMO channel measurements, analysis, and modeling, which were presented previously in the first article in this series of four, are utilized to develop compact and distributed antenna arrays. Parallel activities led to research into low-complexity MIMO single-user spacetime coding techniques, as well as SISO and MIMO multi-user CDMA-based transceivers for B3G systems. As well as feeding into the industry’s in-house research program, significant extensions of this work are now in hand, within Mobile VCE’s own core activity, aiming toward securing major improvements in delivery efficiency in future wireless systems through crosslayer operation

Improved iterative parallel interference cancellation receiver for future wireless DS-CDMA systems

We present a new turbo multiuser detector for turbo-coded direct sequence code division multiple access (DS-CDMA) systems. The proposed detector is based on the utilization of a parallel interference cancellation (PIC) and a bank of turbo decoders. The PIC is broken up in order to perform interference cancellation after each constituent decoder of the turbo decoding scheme. Moreover, in the paper we propose a new enhanced algorithm that provides a more accurate estimation of the signal-to-noise-plus-interference-ratio used in the tentative decision device and in the MAP decoding algorithm. The performance of the proposed receiver is evaluated by means of computer simulations for medium to very high system loads, in AWGN and multipath fading channel, and compared to recently proposed interference-cancellation-based iterative MUD, by taking into account the number of iterations and the complexity involved. We will see that the proposed receiver outperforms the others especially for highly loaded systems

Space time transceiver design over multipath fading channels

Imperial Users onl

High-Level Design for Ultra-Fast Software Defined Radio Prototyping on Multi-Processors Heterogeneous Platforms

International audienceThe design of Software Defined Radio (SDR) equipments (terminals, base stations, etc.) is still very challenging. We propose here a design methodology for ultra-fast prototyping on heterogeneous platforms made of GPPs (General Purpose Processors), DSPs (Digital Signal Processors) and FPGAs (Field Programmable Gate Array). Lying on a component-based approach, the methodology mainly aims at automating as much as possible the design from an algorithmic validation to a multi-processing heterogeneous implementation. The proposed methodology is based on the SynDEx CAD design approach, which was originally dedicated to multi-GPPs networks. We show how this was changed so that it is made appropriate with an embedded context of DSP. The implication of FPGAs is then addressed and integrated in the design approach with very little restrictions. Apart from a manual HW/SW partitioning, all other operations may be kept automatic in a heterogeneous processing context. The targeted granularity of the components, which are to be assembled in the design flow, is roughly the same size as that of a FFT, a filter or a Viterbi decoder for instance. The re-use of third party or pre-developed IPs is a basis for this design approach. Thanks to the proposed design methodology it is possible to port "ultra" fast a radio application over several platforms. In addition, the proposed design methodology is not restricted to SDR equipment design, and can be useful for any real-time embedded heterogeneous design in a prototyping context

Robust synchronization for PSK (DVB-S2) and OFDM systems

The advent of high data rate (broadband) applications and user mobility into modern wireless communications presents new challenges for synchronization in digital receivers. These include low operating signal-to-noise ratios, wideband channel effects, Doppler effects and local oscillator instabilities. In this thesis, we investigate robust synchronization for DVB-S2 (Digital Video Broadcasting via Satellite) and OFDM (Orthogonal Frequency Division Multiplexing) systems, as these technologies are well-suited for the provision of broadband services in the satellite and terrestrial channels respectively.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Performance study of air interface for broadband wireless packet access

Ph.DDOCTOR OF PHILOSOPH