David Navratil

Overload Control Method for Synchronized MTC Traffic in GERAN

Increasing attention has been drawn in Machine Type Communications (MTC), also known as Machine to Machine (M2M) Communications, since it enables implementation of new services, and expansion of revenue sources for mobile equipment manufacturers and mobile network operators. This potential is high, but some issues have to be solved to enable the wide application of MTC services, especially those which could request connections in a synchronized manner. In GSM networks, synchronized channel requests can result in signaling channel overload, which would delay the access procedure for all users trying to access the network. This paper presents a solution for this problem, in which devices connecting in a periodical manner request a future network access already during a previous connection. Simulation results have shown that by using this technique, overload on the access channels is reduced, improving the access delay of normal users and enabling more MTC devices to be included in the network.

Higher Order Modulations and GSM/EDGE Radio Access Network Evolution

The GSM/EDGE radio access network (GERAN) is continuously evolving to support higher peak data rates and to improve coverage. The evolution process is controlled by Third Generation Partnership Project (3GPP) specification work, within the technical specification group (TSG) GERAN and its working groups. One of the proposals how to increase the radio network performance is the usage of higher order modulations such as quadrature amplitude modulation (QAM). That could be seen as a straight step when compared to the introduction of the additional 8-PSK modulation in 3GPP Release 99. The performance evaluation of higher order modulation namely 16-QAM in GSM environment is presented. A comparison with other candidates such as the dual symbol rate is discussed. The effects of transceiver and receiver impairments, frequency hopping, and power amplifier non-linearity are examined separately with the help of a link layer simulator. The obtained results are compared with 3GPP objectives approved on the 24th TSG GERAN meeting