Signaling Enhancement for Machine Type Communications in GERAN Using Orthogonal Sub-Channels

Machine type communications have emerged with new types of applications and revenue sources both for network operators and cellular/network equipment companies. This new kind of service may increase significantly the number of devices accessing the network in the next few years, and could have some impacts over the current services, namely normal voice and data services. One important concern is related to effects of extreme cases where MTC devices may act in a synchronized way. In GSM networks, the signaling capacity may be temporarily blocked, limiting the access of normal services for some seconds, or even minutes. This paper proposes one solution for overload problem caused by MTC device synchronization using the Orthogonal sub- channels technique (OSC). Statistical analysis over the effects of synchronized MTC devices are used to provide an overview on the achievable access procedure delay reduction when using this technique. The proposed technique has proven to decrease the average delay of normal services by 70% and to reduce by 50% the overload period of the signaling channels.