35 research outputs found
Location-Quality-aware Policy Optimisation for Relay Selection in Mobile Networks
Relaying can improve the coverage and performance of wireless access
networks. In presence of a localisation system at the mobile nodes, the use of
such location estimates for relay node selection can be advantageous as such
information can be collected by access points in linear effort with respect to
number of mobile nodes (while the number of links grows quadratically).
However, the localisation error and the chosen update rate of location
information in conjunction with the mobility model affect the performance of
such location-based relay schemes; these parameters also need to be taken into
account in the design of optimal policies. This paper develops a Markov model
that can capture the joint impact of localisation errors and inaccuracies of
location information due to forwarding delays and mobility; the Markov model is
used to develop algorithms to determine optimal location-based relay policies
that take the aforementioned factors into account. The model is subsequently
used to analyse the impact of deployment parameter choices on the performance
of location-based relaying in WLAN scenarios with free-space propagation
conditions and in an measurement-based indoor office scenario.Comment: Accepted for publication in ACM/Springer Wireless Network
Signaling Design for Cooperative Resource Allocation and its Impact to Reliability
Decentralized cooperative resource allocation schemes for robotic swarms are
essential to enable high reliability in high throughput data exchanges. These
cooperative schemes require control signaling with the aim to avoid half-duplex
problems at the receiver and mitigate interference. We propose two cooperative
resource allocation schemes, device sequential and group scheduling, and
introduce a control signaling design. We observe that failure in the reception
of these control signals leads to non-cooperative behavior and to significant
performance degradation. The cause of these failures are identified and
specific countermeasures are proposed and evaluated. We compare the proposed
resource allocation schemes against the NR sidelink mode 2 resource allocation
and show that even though signaling has an important impact on the resource
allocation performance, our proposed device sequential and group scheduling
resource allocation schemes improve reliability by an order of magnitude
compared to sidelink mode 2
Cultural Distance and Firm Internationalization:A Meta-Analytical Review and Theoretical Implications
This paper presents the most comprehensive review and meta-analysis of the literature on cultural distance and firm internationalization to date. We analyze the effects of cultural distance on key strategic decisions throughout the entire process of internationalization. For the preinvestment stage, we examine the decisions on where to invest (location choice), how much to invest (degree of ownership), and how to organize the foreign expansion (entry and establishment mode). For the postinvestment stage, we examine the decisions of how to integrate the foreign subsidiary into the organization (transfer of practices) as well as the performance effects of cultural distance at both the subsidiary and the firm level. We find that firms are less likely to expand to culturally distant locations but if they do, they prefer greenfield investments and integrate subsidiaries more through transfer of management practices. Cultural distance does not seem to affect how much capital firms invest and whether they enter through a joint venture or full ownership. Interestingly, cultural distance has a strong negative effect on subsidiary performance but no effect on the performance of the whole multinational company. In addition, we find that the effects of cultural distance are not sensitive to time, but they are sensitive to the cultural framework used (e.g., Hofstede vs. Global Leadership and Organizational Behavior Effectiveness) and the home country of the company (developed vs. emerging market). Based on our study, we feel confident to offer some theoretical insights, recommendations for improving the validity and reliability of cultural-distance research, and ideas for future research
Simulating Mobile Ad Hoc Networks: Estimation of Connectivity Probability
The network connectivity is one of the important parameters for ad hoc networking, where the communication between nodes relies on the multihop links. It can have a significant impact on the system performance. Therefore, it is important to be aware of the network properties for the correct interpretation of simulation results. The paper shows how to define and evaluate the connectivity probability of a mobile network where the position of the nodes and the link quality changes over time. A number of mobility models is considered including Virtual World model based on the mobility measurements of a multi-player game
Exploiting cooperation for performance enhancement and high data rates
Abstract — In this paper, we discuss an approach to increase wireless bandwidth utilization based on cooperative network architecture, referred to as Cellular Controlled Peer-to-Peer (CCP2P) communication. This approach goes beyond the concepts used in composite networks, focused mainly on coverage extension and data relaying. In CCP2P networks, besides being connected to an ”outside world ” using cellular links, a group of terminals in close proximity form a cooperative cluster. Using peer-to-peer connections CCP2P has the potential to overcome many important limitations of the cellular networks and offer higher data rates and better Quality of Service. Four practically relevant scenarios of CCP2P applications are presented as illustrative examples and discussed in detail. This paper shows that performance gain can be achieved only by cooperative behavior of terminals in the cluster. The importance of rules of cooperation for CCP2P communication is underlined and a discussion on their realization in cooperative networks is provided. Index Terms — cooperation, network architecture, bandwidth utilization, efficiency I
Impact of Different Mobility Models on Connectivity Probability of a Wireless Ad Hoc Network
Based on ideas and methods of ergodic theory this paper presents a new approach investigating mobile ad hoc network connectivity. It is shown how to define and evaluate the connectivity probability of a mobile network where the position of the nodes and the link quality changes over time. This methodology is applied to the random direction mobility model. The obtained results are further illustrated on a scenario with obstacles with different propagation models of the signal. The results of the paper consist of a number of theoretical insights and proofs, which are interesting to researchers in the area of ad hoc networking, since they highlight the important issue of mobile ad hoc network connectivity