Energy Efficient Uplink Resource Allocation in LTE Networks with M2M/H2H Co-existence under Statistical QoS Guarantees

Recently, energy efficiency in wireless networks has become an important objective. Besides the growing proliferation of smartphones and other high-end devices in conventional Human-to-Human (H2H) communication, the introduction of Machine-to-Machine (M2M) communication or Machine Type Communication (MTC) into cellular networks is another contributing factor. In this paper, we investigate Quality-of-Service (QoS) driven energy efficient design for the uplink of LTE networks in M2M/H2H co-existence scenarios. We formulate the resource allocation problem as a maximization of effective capacity based bits-per-joule capacity under statistical QoS provisioning. The specific constraints of SC-FDMA (uplink air interface in LTE networks) pertaining to power and resource block allocation not only complicate the resource allocation problem, but also render the standard Lagrangian duality techniques inapplicable. We overcome the analytical and computational intractability by first transforming the original problem into a Mixed Integer Programming (MIP) problem and then formulating its dual problem using Canonical duality theory. The proposed energy efficient design is compared with spectral efficient design along with Round Robin (RR) and Best Channel Quality Indicator (BCQI) algorithms. Numerical results, which are obtained using the Invasive Weed Optimization algorithm, show that the proposed energy efficient uplink design not only outperforms other algorithms in terms of energy efficiency while satisfying the QoS requirements, but also performs closer to the optimal design.