Frequency Domain Resource Allocation Research Articles

Practical Scheduling Algorithms With Contiguous Resource Allocation for Next-Generation Wireless Systems

This letter proposes three novel resource and user scheduling algorithms with contiguous frequency-domain resource allocation (FDRA) for wireless communications systems. The first proposed algorithm jointly schedules users and resources selected adaptively from both ends of the bandwidth part (BWP), while the second and third ones apply disjoint user and resource selection with either single-end or dual-end BWP strategies. Distinct from existing contiguous FDRA approaches, the proposed schemes comply with standards specifications for fifth-generation (5G) and beyond 5G communications, and have lower computational complexity hence are more practical. Simulation results show that all of the proposed algorithms can achieve near-optimal performance in terms of throughput and packet loss rate for low to moderate traffic load, and the first one can still perform relatively well even with a large number of users.

Channel-, Queue-, and Delay-Aware Resource Allocation in Buffer-Aided Relay-Enhanced OFDMA Networks

Resource allocation is an important factor in providing different varieties of services in next-generation broadband wireless systems. In this paper, we consider dynamic routing and subchannel allocation for providing quality of service (QoS) in the downlink of orthogonal frequency-division multiple-access (OFDMA) networks enhanced with buffering relays. Specifically, we consider satisfying the QoS requirements of both delay-sensitive users with the goal of meeting packet deadline constraints and delay-tolerant users who need guarantees on their average throughputs. We provide a framework for “time-domain scheduling” and “frequency-domain resource allocation,” and based on this, we propose novel channel-, queue-, and delay-aware policies for formulating and solving the joint routing and resource allocation problem. In particular, these policies take different approaches to decide on the set of users considered in the utility function, the delay budget division between the base station and relays, the routing path of delay-sensitive users' packets, and the computation of minimum rate requirements for serving their queues. We present an iterative algorithm to solve the resulting problems. Numerical results show significant improvements in throughput and delay performance of the proposed resource allocation mechanisms compared with existing algorithms.

Power control and group proportional fairness for frequency domain resource allocation in L-SC-FDMA based LTE uplink

Resource allocation in Long Term Evaluation (LTE) uplink is challenging because of two reasons: (1) it requires contiguous resource block allocation and (2) high complexity due to per user based power allocation among resource blocks. This paper presents a low complexity, optimal power resource allocation scheme for LTE uplink. We propose Virtual Cluster-based Proportional Fairness scheme that exploits the link adaptation information available at MAC layer to form virtual clusters. The distributed proportional fair scheduler ensures a minimum throughput for all users in the coverage area by assigning contiguous resource blocks, proportional to the throughput and the number of users in a particular cluster or group. Then, it allocates power to each resource block through water-filling algorithm which gives 20.2 % increase in average user throughout compared to equal power allocation. Simulations have been performed using practical scenarios of uniformly distributed users in Rician fading environment. Mathematical framework has been devised for network planning to get the best possible fairness with promising level of quality of service.

Fairness Aware Group Proportional Frequency Domain Resource Allocation in L-SC-FDMA Based Uplink

This paper presents virtual clusters based proportional fairness and resource allocation scheme for Localized Single Carrier Frequency Division Multiple Access (L-SC-FDMA). L-SC-FDMA has been selected as the uplink transmission scheme in 3GPP Long Term Evolution (LTE) due to its low Peak to Average Power Ratio (PAPR) over OFDMA in general and high rate-sum capacity over Interleaved SC-FDMA in particular. Virtual cluster-based proportional fairness (VCPF) scheduler exploits the link adaptation information available at MAC layer to form virtual clusters. The distributed proportional fairness scheduler ensures a minimum throughput for all users in the coverage area by assigning contiguous RBs, proportional to the throughput and the number of users in a particular cluster or group. Simulations have been performed using practical scenario of uniformly distributed users in Rayleigh faded coverage area and design formulas have been devised for network planning to get the best possible fairness with promising level of quality of service (QoS).

Multiuser frequency-time domain radio resource allocation in downlink OFDM systems: Capacity analysis and scheduling methods

In this paper, we propose an adaptive multiuser frequency-time domain radio resource allocation model for the downlink OFDM systems, which efficiently exploits the time diversity, frequency diversity as well as multiuser diversity in the time, frequency and user domain, respectively. Next we give an in-depth capacity analysis of the proposed frequency-time domain radio resource allocation which achieves much higher capacity (spectral efficiency) than the conventional frequency domain resource allocation. Then according to the allocation algorithm’s computational complexity, two different-complexity adaptive resource allocation algorithms—algorithm A and algorithm B—are proposed which adopt a two-step allocation method to reduce the scheduling complexity and meanwhile improve the scheduling performance. Simulation results show that though the performance of algorithm A and B is slightly different, both of the proposed algorithms yield much higher spectral efficiency and much lower outage probability than conventional OFDM-TDMA scheme or random allocation without any scheduling policy.