Survey of downlink control channel resource allocation techniques in LTE

In LTE, resource allocation technique is a non-standardized but an essential process to achieve high data rate and low latency at user end. Any resource allocation technique is incomplete if control channel (PDCCH) resource allocations are not considered in allocation process and only shared data channel (PDSCH) resources are considered. It should be noted that a user would be scheduled or not scheduled is determined from PDCCH resources. Therefore, PDCCH resource allocation is important for scheduling users. In practical scenario, there is constraint in availability of PDCCH resources with respect to number of users demanding resources. So, it is difficult to allocate resources to all users simultaneously. An effective PDCCH resource allocation technique is necessary in order to schedule maximum number of users in limited number of resources. Further, the technique should maintain fairness and throughput of users. The paper discusses different parameters which talks about control channel (PDCCH) scheduler. This paper provides a complete understanding of PDCCH resource allocation technique based on different allocation parameters. Requirement of improvement in PDCCH channel allocation techniques in LTE-Advanced is also discussed in end of the paper.