Dynamic Spectrum Allocation Technique Research Articles

Improvements for Uplink Long Term Evolution (UL-LTE) in Heterogeneous Network using Dynamic Spectrum Allocation Technique

Several interference mitigation strategies can be used in LTE networks to meet the consumers' increasing need for faster data speeds. Dynamic Spectrum Allocation (DSA), which maintains spectrum in a converged radio system and distributes it across all participating radio terminals, is one of the most promising solutions. However, the fundamental obstacle to achieving increased network capacities is increased inter-cell interference. The aim of this paper is to analyse the effectiveness of a newly proposed DSA technique by comparing its bit error rate (BER) and throughput (TP) with a typical uplink LTE configuration. To maximise throughput in a heterogeneous network, the suggested DSA technique utilises the Nash Bargaining Solution (NBS) scheme, a cooperative game theory that could correlate with the bit error rate. The software tool GNU Radio, which offers signal-processing blocks to develop softwaredefined radios and signal-processing systems, was used to create the setups. After the simulations were performed, the BER values were recorded and compared, while the TP values were established and computed appropriately. According to the results, the uplink (UL-LTE) architecture with DSA has an improved TP and a lower BER value. As a result, spectral efficiency can also be improved.

Throughput Analysis on Dynamic Spectrum Allocation Technique to Mitigate Interference on LTE Heterogeneous Network

The use of mobile devices has gradually increased over time. It has become a necessity for people to own mobile devices in order to communicate with others all around the world. With increasing number of users, the LTE network service providers need to think of a way on how to enhance their service so that users can experience faster internet experience without any disruption from the network. In a heterogeneous network that consists of several base stations and scores of users, cross-tier interference is bound to occur. Cross-tier interference can cause loss of signal and drop calls. In this paper, a Dynamic Spectrum Allocation (DSA) technique was proposed and implemented in a LTE network configuration. At this juncture, the study only focuses on the segment involving communication downlink. Software development toolkit GNU Radio was used in the assembly of the network configurations. Throughput comparison was then made against a normal LTE network configuration. The throughputs of both configurations were computed and assessed. Configuration embedded with DSA managed to achieve higher throughput. The findings suggest that DSA is a technique capable of mitigating interference for LTE network.

Assessment of Dynamic Spectrum Allocation Technique in Heterogeneous Network

Mobile devices are becoming the priority of access to a growing trend of online services. As services use higher quality images & video, an increase of wireless network capacity is required. In this case, spectrum is a way to go. Even though capacity is important, there are other factors as well, for example, coverage, flexibility and resilience. Dynamic spectrum access technology allows higher transmission power according to location & safe sharing with licensed users (LU). Dynamic spectrum allocation (DSA) technique enhances the spectrum efficiency for the users in Heterogeneous Network. This paper explains about the findings that are observed by two different researches that are related to our research title. The first paper is about the basic OFDM structure using GNU Radio software and implemented using USRP hardware. The second research is about the implementation of Dynamic Resource Allocation for LTE using GNU Radio. The first research explained about the advantages and disadvantages of OFDM configuration. The second research explained more about the implementation of Dynamic Resource Allocation in the uplink and downlink configuration, and are tested using three algorithms; Max-sum, max-min and maxproduct. All the results are obtained from GNU Radio. However, the results are not implemented using USRP because of the short amount of time. Based on these two researches, we identified the advantages and disadvantages of the proposed designs and develop our own design to mitigate the cross-tier interference in multi-tiers HetNets.

Adaptive Bandwidth Allocation Scheme for Cognitive Radios

In recent past, cognitive radio has come out to as a promising solution to the spectrum scarcity problem. It tends to increase the spectrum utilization by making use of underutilized frequencies with the help of dynamic spectrum allocation technique. In this paper, we present one such scheme for bandwidth allocation to cognitive radio. Our proposal helps the channel distributor to decide the quantity of bandwidth that can be allocated to an unlicensed user at any given time. Fuzzy rules are used to optimize the bandwidth allocation based on three antecedents as: arrival rate of both licensed and unlicensed users and the availability of unoccupied number of channels within the system. The scheme is independent of the service times for user’s requests and thus may be applicable to any service distribution type.

QoS-aware distributed spectrum sharing for heterogeneous wireless cognitive networks

Ubiquitous wireless networking calls for efficient dynamic spectrum allocation (DSA) among heterogeneous users with diverse transmission types and bandwidth demands. To meet user-specific quality-of-service (QoS) requirements, the power and spectrum allocated to each user should lie inside a bounded region in order to be meaningful for the intended application. Most existing DSA methods aim at enhancing the total system utility. As such, spectrum wastage may arise when the system-wise optimal allocation falls outside individual users' desired regions for QoS provisioning. The goal of this paper is to develop QoS-aware distributed DSA schemes using game-theoretic approach. We derive DSA solutions that respect QoS and avoid naively boosting or sacrificing some users' utilities to maximize the network spectrum utilization. Specifically, we propose two game-based DSA algorithms: one resorts to proper scaling of the transmission power according to each user's useful utility range, and the other embeds the QoS factor into the utility function used during gaming. To evaluate DSA schemes from a practical QoS perspective, we introduce two new metrics, namely ''system useful utility'' and ''fraction of QoS-satisfied users''. Simulations confirm that the proposed DSA techniques outperform existing QoS-blind game models in terms of the spectrum sharing efficiency in heterogeneous networks. Convergence analysis of the proposed QoS-aware DSA algorithms is also provided.