Efficient Downlink Control Resources Allocation Scheme for Machine-Type Communications in LTE-A Networks

LTE-Advanced (LTE-A) is expected to be one of the main platforms for Massive Machine-Type Communications (mMTC) system. The provision of Quality of Service (QoS) in future cellular networks strongly depends on efficient allocation of resources in the control channel. However, the design of the control channel is not flexible enough to support the massive number of devices typical of the Machine-to-Machine (M2M) communication. In the LTE-A standard, the control signalling process is performed over the Packet Downlink Control Channel (PDCCH). In this process, two issues need to be addressed: the determination of the number of resources to be allocated to the PDCCH and the scheduling of control messages of the terminals in the PDCCH. This paper presents a scheme for control resource allocation aware of the availability of resources for scheduling control messages of the terminals. The main advantage of the proposed scheme is the reduction of the joint list fragmentation, and consequently the number of blocked control messages. Results indicate that performance can be significantly improved without increasing the complexity of the PDCCH resources scheduling process.