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One of the key building blocks of the newly emerging 5th generation (5G) wireless communication system are ultra dense small cells. In this paper, the system performance of such a deployment is studied for scenarios where there are individual deadlines to serve data packets. A proactive delay-minimizing scheduling method (PDMS) is proposed to minimize the number of dropped packets due to missed deadlines...
Network-facilitated device to device (D2D) communication is expected to play a central role in 5th generation cellular systems, as this allows to substantially reduce the end-to-end latency in mission-critical communication use cases, but also to obtain network and spectral efficiency improvements through the exploitation of proximity gains, hop gains and reuse gains in mobile broadband scenarios...
This chapter provides an overview of analog modulation and frequency modulation (FM). Information is encoded through a variation of the phase of the carrier wave in phase modulation (PM). An alternative approach is to not map a zero data bit to a carrier signal which is turned off, but rather to a carrier signal with a negative amplitude, which is referred as amplitude shift keying (ASK). A way to...
This chapter provides a comprehensive overview on wireless communications according to the 3GPP technologies of Wideband Code Division Multiple Access (WCDMA) and High Speed Packet Access (HSPA). These technologies are used in the Universal Mobile Telecommunication Standard (UMTS) belonging to the 3rd Generation (3G) of mobile cellular solutions. The radio network controller (RNC) is a part of the...
Ultra dense small cell deployments and a very large number of applications are expected to be the essential aspects of the newly emerging 5th generation (5G) wireless communication system. To match the diverse quality of service requirements imposed by a variety of applications, dynamic TDD is proposed as a solution by enabling flexible utilization of the spectrum for uplink and downlink of each cell...
In 2020, mobile and wireless traffic volume is expected to increase thousand-fold over 2010 figures. Moreover, an increase in the number of wirelessly-connected devices to counts in the tens of billions will have a profound impact on society. Massive machine communication, forming the basis for the Internet of Things, will make our everyday life more efficient, comfortable and safer, through a wide...
Even though some mobile network operators are already ramping up Long Term Evolution (LTE) networks, the biggest portion of mobile network revenues will still be generated in HSPA networks for the coming years. Also, the current exponential increase in mobile data rate demand provides a strong motivation to further evolve HSPA networks in parallel to ramping up LTE. While dual-stream MIMO was already...
Cellular communication systems have traditionally been designed according to the paradigm that base stations serve independent sectors for which inter-sector interference should be minimized. Further, multiple base stations serving multiple sectors are traditionally grouped into a minimum number of sites, in order to reuse infrastructure for cooling, battery backup etc. and minimize site rental cost...
Coordinated Multi-Point (CoMP) appears to be an effective option to combat inter-cell interference in mobile communications. Previous field trials for uplink CoMP have shown that large improvements in spectral efficiency and fairness that are promised by theoretical work can also be achieved in real-world scenarios. However, these results only consider systems with single antenna base stations. We...
Mobile communication systems have evolved over the past decades and each new generation brought new experience to the users enabled by technology innovations, while keeping some well established principles from previous generations. This trend continued up to LTE (Long Term Evolution) Advanced, the predominant 4th generation system which has just been standardized in 3GPP and is being rolled out soon...
Coordinated multi-point (CoMP) has been selected as a key technology feature of LTE-Advanced, as it enables the exploitation of inter-cell interference in order to significantly increase spectral efficiency, especially at the cell-edge. While first field trials on CoMP schemes have delivered the proof-of-concept and shown that a moderate extent of theoretically predicated CoMP gains can indeed be...
Coordinated multi-point (CoMP) in the cellular uplink, offering large improvements in spectral efficiency and fairness, appears to be an effective option to combat inter-cell interference. Current approaches range from coordinated scheduling to coherent joint detection. A major drawback of coherent joint detection is the large extent of additional backhaul infrastructure required for the exchange...
Theoretical analysis of base station cooperation methods have proven their potential for solving interference limitation in today's cellular networks by showing immense capacity and fairness gains. However, a major downside of base station cooperation is the additional information exchanged amongst base stations which has been the motivation for recent work on backhaul efficient cooperation schemes...
Optimization of the energy efficiency is considered not only to positively contribute to the ecological assessment, but gains in importance from operator's point of view as well, since energy costs for running a mobile radio network have an increasing share of the operational expenditure. From this perspective, the utilization of small, low power base stations is regarded as a promising strategy to...
The growing relevance of wireless communications has been driving the research and development to enable cost-efficient support of very high data rates to be delivered to a large number of users. The high bandwidth targets for future networks are reflected in the ITU's call for IMT-Advanced. As interference poses the main limitation in today's networks, cooperative signal processing (often referred...
This paper introduces a new mathematical framework which is used to derive joint uplink/downlink achievable rate regions for multi-user spatial multiplexing between one base station and multiple terminals. The framework consists of two models: the first one is a simple transmission model for uplink (UL) and downlink (DL), which is capable to give a lower bound on the capacity for the case that the...
Theoretical research on coordinated multi-point (CoMP) in the cellular uplink claims large improvements in spectral efficiency and fairness. However, the real-world implementation of CoMP is linked with major challenges such as multi-cell synchronization and multi-cell channel estimation, which have to be addressed to make sure that CoMP finds its way into next generation cellular systems (e.g. LTE-Advanced)...
This paper gives an overview of the objectives and current research activities on interference avoidance in the EC funded research project ARTIST4G. It is the main objective of the ARTIST4G Work Package 1 (WP1), to build forward on the 3GPP LTE Release 8 baseline, proposing a novel fair mobile broadband technological framework in which to design innovative, practical, scalable and cost-effective interference...
The capacity of today's cellular mobile communications systems is mainly limited by inter-cell interference. Multi-cell joint transmission or joint detection schemes are means to overcome this limitation and to actively exploit signal propagation across cell borders rather than treating it as noise. A major downside to multi-cell signal processing is the additional backhaul rate that is required to...
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