Magnus Frodigh

Future-generation wireless networks

Starting with todays 3G standards, future-generation wireless networks are discussed. Two complementing major trends are identified: seamless roaming between different air interfaces, leading to the always best connected concept, and the continuous development of the current third-generation standards. The evolution of WCDMA toward high-speed downlink packet access. aiming for peak rates in the order of 8-10 Mb/s, is described as an example of air-interface evolution. Fourth-generation technologies such as ad hoc networking and multihop networks, still at the research level, are discussed and their impact on wireless communication systems addressed.

Realizing the Tactile Internet: Haptic Communications over Next Generation 5G Cellular Networks

Prior Internet designs encompassed the fixed, mobile, and lately the things Internet. In a natural evolution to these, the notion of the Tactile Internet is emerging, which allows one to transmit touch and actuation in real-time. With voice and data communications driving the designs of the current Internets, the Tactile Internet will enable haptic communications, which in turn will be a paradigm shift in how skills and labor are digitally delivered globally. Design efforts for both the Tactile Internet and the underlying haptic communications are in its infancy. The aim of this article is thus to review some of the most stringent design challenges, as well as propose first avenues for specific solutions to enable the Tactile Internet revolution.

Algogrithms for link adaptation in GPRS

In the General Packet Radio Service (GPRS) development of GSM, four error correcting coding schemes have been defined to allow for variations in radio channel conditions. In this paper, two algorithms for link adaptation (i.e. choosing the most suitable coding scheme for transmission) are discussed. The first one is based on the estimated C/I (ECI) of the transmission and the second one on block error rate (BLER). The results of the study indicate that algorithms based on estimated C/I are superior to those based on block error rate. The improvement in terms of throughput per user is in the order of 10%. Both algorithms are superior to any fixed coding scheme. One problem that is apparent when using link adaptation is the degree of fairness in the system. Unfortunately, both the proposed algorithms show disturbing variations in throughput between different users. This is true also for the ideal case, where throughput is maximized by basing the choice of coding scheme on actual C/I.

Refined Statistical Analysis of Evolution Approaches for Wireless Networks

To meet future traffic and data rate demands, operators have the opportunity to select between a variety of network evolution approaches. This paper presents a new method for evaluating such approaches, in a simple yet operator specific way. The novelty of the method lies in that, with limited complexity, it takes into account not only conventional dimensioning parameters like targeted user experience, average traffic demand, user density and cell sizes, but also three dimensional spatial user and traffic distribution, site specific propagation, and deployment strategies. This is enabled through the use of an explicit city model, capturing the main characteristics of the operators environment. Applying the method to two examples of different cities illustrates the influence of the refinement parameters and their impact on the benefits of two evolution approaches: macro densification and deployment of small cells.