Comparison between Scheduling Techniques in Long Term Evolution

Abstract

Long-Term Evolution (LTE) is a recently evolving technology characterized by very high speed data rate that allows users to access internet through their mobile as well as through other electronic devices. Such technology is intended to support variety of IP-based heterogeneous traffic types. Traffic scheduling plays an important role in LTE technology by assigning the shared resources among users in the most efficient manner. This paper discusses the performance of three types of scheduling algorithms namely: Round Robin, best Channel Quality Indicator (CQI) and Proportional Fair (PF) schedulers representing the extreme cases in scheduling. The scheduling algorithms performances on the downlink were measured in terms of throughput and block error rate using a MATLAB-based system level simulation. Results indicate that the best CQI algorithm outperforms other algorithms in terms of throughput levels but on the expense of fairness to other users suffering from bad channel conditions. ABSTRAK: Teknologi baru Evolusi Jangka Panjang (LTE) sentiasa berubah dan ia bercirikan kelajuan kadar data sangat tinggi yang membolehkan pengguna mengakses internet melalui telefon bimbit dan peranti elektronik lain. Teknologi seperti ini bertujuan menyokong pelbagai jenis trafik heterogen berasaskan IP. Penjadualan trafik memainkan peranan penting dalam teknologi LTE bagi mengagihkan sumber perkongsian secara paling berkesan di kalangan pengguna. Kertas ini membincangkan prestasi tiga jenis algoritma penjadualan iaitu: pusingan Robin, penunjuk kualiti saluran (CQI) terbaik dan penjadualan berkadar adil (PF) yang merupakan kes ekstrem dalam penjadualan. Prestasi penjadualan Algoritma di pautan turun diukur dari segi daya pemprosesan dan kadar ralat blok melalui simulasi sistem menggunakan MATLAB. Hasil kajian menunjukkan algoritma CQI adalah yang terbaik berbanding hasil algoritma lain dari segi tahap daya pemprosesan tetapi algoritma ini menyebabkan pengguna lain mengalami keadaan saluran buruk.KEYWORDS: LTE; round robin; best CQI; proportional fair; scheduling; resource blocks

Mobile femtocell utilisation in LTE vehicular environment: Vehicular penetration loss elimination and performance enhancement

“…This type of scheduling refers to the amount of resources allocated within a given time window to UEs with better channel quality in order to offer high cell throughput as well as fairness satisfactory. The PF scheduling mechanism has been presented by figure (5) [8]. This scheduling policy works as the following; firstly, the scheduler sorts the UEs in descending order according to the proportional fair metric and then it picks up only some of the UEs depending on the availability of the CCE, the PRBs and UE's Channel Quality Indicator (CQI).…”

On the Performance Bounds of LTE- A System under Varied UE Distributions

“…Moreover many forms of scheduling algorithms are available but we will consider only the RR scheduling algorithm in this handout. In Round Robin (RR) scheduling [6] the stations are allocated the RB's one next another deprived of CQI to each consumer in definite time break. The process of allocating the resource is that firstly the consumer will use the resource for the specified time break and afterwards the achievement of time then these available resources is allocated to a new consumer.…”

“…Furthermore, RR springs each UE an equivalent chance to acquire RB's, the whole throughput is abundant inferior than further schedules since the RR not ensures the condition of channel. In LTE, dissimilar UEs must have altered facilities with QoS necessities and it is very problematic to permit each SN for similar RBs for the equivalent option since it will decline the resource effectiveness [2]. The downlink physical source is characterized by a time-frequency reserve network containing of numerous Resource Blocks (RB).…”

Self-Organizing Networks

“…Then, one of the users ready to transmit starts sending data. If the user uses up all the unit of time, the system allocates the resources to another user [51].…”