Mohamad Kalil

Wireless resources virtualization in LTE systems

This paper proposes a framework for Wireless Resource Virtualization (WRV) in Long Term Evolution (LTE) systems. An shared radio access network connects Multiple Mobile Network Operators (MNOs) and allocates radio resources to their users. We formulate the WRV problem as a Binary Integer Programming (BIP) problem. Subsequently, a low complexity iterative algorithm is presented to solve the BIP problem. The proposed framework allows MNOs to customize their scheduling policies to fit their service requirements and business models. Essential considerations like isolation across MNOs, complexity, and efficient resource utilization are also considered and evaluated. The results show that the proposed framework can efficiently share the radio resources between MNOs while maintaining the sharing agreement conditions.

QoS-Aware Power-Efficient Scheduler for LTE Uplink

The continuous increase of mobile data traffic has created a substantial demand for high data rate transmission over mobile networks. However, mobile devices are provided with small batteries that can be drained quickly by high data rate transmission. Motivated by the fundamental requirement of extending the battery utilization time per charge of mobile devices, this work presents two power-efficient schedulers for mixed streaming services in LTE uplink systems. Our objective is to minimize the total transmission power for all users. The proposed schedulers are subject to rate, delay, contiguous allocation, and maximum transmission power constraints. We first consider an optimal scheduler that uses binary integer programming (BIP). Then, we propose an iterative scheduler that performs a low-complexity greedy algorithm which solves the BIP problem. We compare the performance of the proposed schedulers to the state-of-the-art schedulers such as the energy-aware resource allocation (EARA) [1] and the proportional fair (PF) [2] in terms of rate, delay, average transmission power and complexity. Simulation results show that the proposed schedulers offer a remarkable transmission power reduction as compared to the PF and the EARA schedulers, and satisfy the QoS requirements.

Low-Complexity Power-Efficient Schedulers for LTE Uplink With Delay-Sensitive Traffic

This paper investigates power-efficient scheduling for the uplink of Long-Term Evolution (LTE) systems. The aim is to minimize the total transmit power while satisfying particular delay requirements. The scheduling process is formulated as a dynamic programming problem. We show that the global optimal solution requires knowledge of future arrival rates and future channel gains for all users. Alternatively, we propose two low-complexity heuristic schedulers. The first heuristic scheduler controls the maximum allowable transmit power (MATP) for each user based on the queue length. In particular, if the queue length of a user is relatively small, the scheduler reduces the users transmission rate and the MATP to minimize the total transmit power. On the other hand, when the queue length is large, the scheduler increases both the transmission rate and the MATP to satisfy the delay requirements. The second heuristic scheduler controls the minimum acceptable bit-per-Watt ratio (BPWR) for each user. Users can only transmit if their BPWRs are greater than an acceptable level, which allows only high power-efficient transmission. The minimum acceptable BPWR is adaptively changed based on the queue length of each user. The performance of the heuristic schedulers is evaluated and compared with the optimal solution and other existing schedulers.

Efficient Low-Complexity Scheduler for Wireless Resource Virtualization

This letter proposes an efficient low-complexity scheduler to virtualize the wireless resource blocks (RBs) and share them between users of multiple mobile network operators (MNOs). The scheduler aims at maximizing the throughput while maintaining access proportional fairness (APF) among users as well as MNOs. Normalized signal-to-noise ratio (SNR) selection criterion is used to impose APF between the users of each MNO, while APF between MNOs is maintained by assigning different weights to the normalized SNRs. The optimal weights for all MNOs are computed offline using iterative search method. Analytical and simulation results show that the proposed scheme can maintain APF at the user and MNO levels. Moreover, the throughput of the proposed scheduler is consistently higher than in the static sharing scenario.

Power-efficient QoS scheduler for LTE uplink

This work presents a power-efficient multi-user scheduler for mixed streaming services in multi-user LTE uplink systems. We propose an optimal and iterative formulation for the sum-power minimization subject to rate, delay, contiguous allocation, and maximum transmitted power constraints. The results are presented for the rate, delay, average transmitted power and complexity.

Performance evaluation of genetic algorithms for resource scheduling in TLE uplink

Single Carrier Frequency Division Multiple Access (SC-FDMA) is used for uplink data transmission in Long Term Evolution (LTE) systems. SC-FDMA requires contiguous resource blocks (RBs) allocation for each user, which challenges the uplink resource allocation in LTE. The contiguity constraint turns the allocation problem into a non-convex optimization problem. The optimal solution is achieved by solving a binary integer programming (BIP) problem which is computationally-expensive. In this work, we propose a genetic algorithm that is able to solve the resource allocation problem in the LTE uplink. The proposed algorithm maintains all the system constraints and provides a solution with lower complexity compared with the optimal solution. The proposed GA is evaluated and compared with the optimal approach in terms of efficiency and time complexity.

Wireless resource virtualization: opportunities, challenges, and solutions

Wireless resource virtualization WRV is currently emerging as a key technology to overcome the major challenges facing the mobile network operators MNOs such as reducing the capital, minimizing the operating expenses, improving the quality of service, and satisfying the growing demand for mobile services. Achieving such conflicting objectives simultaneously requires a highly efficient utilization of the available resources including the network infrastructure and the reserved spectrum. In this paper, the most dominant WRV frameworks are discussed where different levels of network infrastructure and spectrum resources are shared between multiple MNOs. Moreover, we summarize the major benefits and most pressing business challenges of deploying WRV. We further highlight the technical challenges and requirements for abstraction and sharing of spectrum resources in next generation networks. In addition, we provide guidelines for implementing comprehensive solutions that are able to abstract and share the spectrum resources in next generation network. The paper also presents an efficient algorithm for base station virtualization in long-term evolution LTE networks to share the wireless resources between MNOs who apply different scheduling polices. The proposed algorithm maintains a high-level of isolation and offers throughput performance gain. Copyright