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Because of the gains like diversity, throughput, and the coverage extension provided by the multiple-input multipleout (MIMO) systems, it has been part of the various wireless communications standards. However, to reap the benefits offered by MIMO systems in size-constrained nodes, used in wireless communications, has been a challenging issue. To address this challenge, cooperative communications has been introduced as an implementable way to exploit the multi-antenna (MIMO) gains in small size nodes. Various schemes or protocols have been devised to address the way by which cooperative communications actually takes place. In this article, we propose and investigate a novel scheme which provides a way to combine the benefits of space-time codes and network coding for cooperative communications. In this scheme, the cooperating users using space-time codes are assisted by the availability of a fixed relay node proposed for the future wireless networks. We compare our scheme with cooperative communications using Alamouti scheme and non-cooperative communications. With analytical results, we prove that the proposed scheme offers diversity gain of order three while cooperative communications using Alamouti scheme offers two and non-cooperative communications offers diversity order of one only. Moreover, the proposed relay assisted scheme outperforms by 15% in terms of multiplexing gain, the cooperative communications scheme being compared.

with the emergence of internet and World Wide Web, traditional businesses got a new opportunity to compete globally. Traditional bricks-and-mortar businesses became electronic business (e-business) by utilizing Information and Communication Technology (ICT) tools. A new term of Mobile Commerce (M-Commerce) has created tremendous spectrum of business opportunities for businesses. Although there has been large scale adoption of M-Commerce in developingeconomies, but little growth is observed in developing economies such as Pakistan. There are doubts that users of Mcommerce demonstrate a lack of enthusiasm, which may be due to lack of trustworthiness. Based on the well-known and widely used Technology Acceptance Model (TAM), this research study provides the conceptual framework, underpinning the relationship of trust with the adoption of Mcommerce in Pakistan. The aim of this paper is to study the role of trust and its relationship with the acceptance of MCommerce in Pakistan.