Kyeongpyo Kim

QoS provisioning in domain based mobile IP networks

In this paper, we propose a scalable domain-level call admission control (CAC0 algorithm supporting a novel dynamic reservation method in mobile IP (MIP) enable Internet. MIP tunnels enable for a mobile node to move to another subnet on a session. In order to prevent a service quality from being degraded in MIP networks, it is necessary to deliberate the quality of service (QoS) provisioning on the MIP tunnels especially for roaming mobile nodes (MNs) to foreign networks Our CAC algorithm keeps a handoff dropping probability (HDP) below a pre-defined value without regard to overloads of mobility agents (MAs). Our proposed scheme uses the number of calls that will be handed off from neighboring MAs and the number of calls in the current MA. We assume that each class has both a HDP and a desired bandwidth. The proposed admission control algorithm can be expanded to serve not only single class but also multi-class with different QoS requirements. Furthermore, we introduce an aggregated dynamic resource allocation method to reflect incoming call patterns and to reduce the number of reservation signals for the tunnels which can cause the increase in network traffics and the data loss during the handoff processing. We show that our scheme guarantees the given HDP and reduces the number of reservation signals comparing trunk reservation methods.

Evaluation of 60 GHz MIMO Channel Capacity in the Conference Room STA-STA Scenario

The 2×2 MIMO channel capacity is studied for millimeter wave radio propagation between two stations (STA-STA) on a table in a conference room. It is focused on whether a small antenna spacing enables a high MIMO channel capacity or not. The effect of reflection is also investigated on the MIMO channel capacity. For reflection, both two cases are considered: the reflection without scattering (where there are only deterministic central rays) and the reflection with scattering (where there are stochastic pre-cursor and post-cursor rays as well). The dimension of the conference room and other most channel parameters are employed, as suggested in the IEEE802.11ad 60 GHz channel model. It is shown from the simulation results that the scattering of such power as suggested in IEEE802.11ad 60 GHz channel model does not have significant effect on the MIMO channel capacity. The capacity is shown to depend on the multiple antenna orientation and the orientation of reflectors (that is, whether the reflector is either wall or ceiling). It is found that there is a locally optimal value in the region of small antenna spacings to maximize the MIMO channel capacity over that region.