Hybrid relay selection‐based scheme for UWB BANs combining MB‐OFDM and decode‐and‐forward cooperative architectures

Abstract

Wireless body area networks (WBANs) is now a well-accepted technology that provides not only efficient and remote health-care services but also targets the integration of future multimedia applications, in which high data rate is compulsory. UWB communication is one of the key solutions that afford such rates, and its extended version, multiband OFDM (MB-OFDM) has recently shown its efficiency with WBANs. However, increasing the data rates may come at the expense of the data reliability which is a critical issue in biomedical applications. Cooperative diversity has proven its ability in offering such robustness to channel errors while avoiding to use multiple antennas. Indeed, a single antenna terminal is sufficient to achieve diversity benefits by sharing its physical resources with cooperating single antenna relays. Aiming at providing a viable compromise between the data rate and accuracy in low-profile UWB body networks, to incorporate a decodeand-forward-based cooperative architecture in MB-OFDM system by resorting to opportunistic relaying approach is proposed, which retains only the best on-body relay to forward the information to the destination, thereby significantly reducing the complexity.

A Hybrid Spatial Adaptive Modulation and Frequency Stochastic Approach for MU-MIMO-OFDM Systems in the Context of Underlay Cognitive Radios

“…On the other hand, and due to the high-data rates involved in current and future communications, orthogonal frequency division multiplexing (OFDM)-based techniques are commonly adopted to fulfill these rate needs and combat the inherent frequency selectivity of the resulting channels. In this context, combining OFDM and MIMO capabilities was shown to further improve the achievable spectral efficiency [12][13][14]. Due to the fact that the resulting system should support the increasing number of subscribers to wireless services, a trend towards the investigation of MU-MIMO-OFDM architectures has rather been noted these last years.…”

“…Due to the fact that the resulting system should support the increasing number of subscribers to wireless services, a trend towards the investigation of MU-MIMO-OFDM architectures has rather been noted these last years. It was shown in [13,15] that the combination of multi-user, spatial and frequency diversities with AM improves the overall system performance in a non-cognitive setting.…”

“…Subsequently to the singular value decomposition (SVD) of the MIMO channel matrix, the first one concerns the application of the power-only AM method on each MIMO subchannel pertaining to each subcarrier of each SU, under BER and total power constraints. Power waterfilling is carried out over only the space domain because no gain is noted when performing it simultaneously over space and time domains [12,13,15,16]. This leads to the evaluation of the average power budget in the second stage which is equal to the allocated power per each eigen-channel.…”

Integration of Spatial Modulation Scheme With Code Division Multiple Access for VIVO Based Frequency Selective Nano Sensor Networks

“…In [1], the authors propose a non-intrusive breathing monitoring system using the C-Band sensing technique. In [2], cooperative techniques are exploited to enhance the coverage and the reliability of WBANs. Interference cancellation in WBANs is targeted in [3], while [4] introduces an FPGA-based realistic solution to reduce the implementation complexity by recoursing to compressed sensing tools.…”