Performance Of LTE System Research Articles

A BCS code in the f-OFDM system: a promising candidate for 5G wireless communication systems

Recently, a novel BCS code differing from conventional concatenated (RS/BCH) codes has been proposed for LTE system. It achieved a significant improvement in the LTE system performance better than single codes and familiar concatenated (RS/BCH) codes. However, LTE systems that primarily depend on orthogonal frequency-division multiplexing (OFDM), no longer meet the demand of wireless-communication systems and their high data-rate requirements because of the rapid growth in the service aspect of such systems. In addition to high out-of-band emission (OOBE) and big peak to average power ratio (PAPR) of OFDM, it doesn’t meet the demand of 5G diverse service scenarios. Meanwhile, filtered OFDM (f-OFDM) is considered a candidate technique for 5G wireless communication systems which have OFDM features as well low OOBE. However, a trade-off exists among reducing OOBE, bit error rate (BER) degradation, and high PAPR. In this work, the BCS code is proposed for f-OFDM to enhance its system performance, while a root-raised-cosine windowed finite impulse response (FIR) filter is selected in f-OFDM to reduce OOBE levels. Results show that in the BPSK and QPSK modulation schemes, f-OFDM achieves a low level of OOBE after using an FIR digital filter against a high level of OFDM. Meanwhile, the proposed system using the BCS code enables remarkable improvement in BER performance and helps reduce PAPR better than conventional OFDM systems. Therefore, considering these features, the proposed system using the BCS code can be presented as a candidate for 5G wireless-communication systems.

Using AI in wireless communication system for resource management and optimisation

The existence of Artificial Intelligence (AI) can be seen in everyday scenarios. Nowadays, the produced data by both machine and human is overwhelming in which exceeded the ability of humans to understand and digest to make decisions depending on that data. Thus, a hand of help from AI is needed to overcome such challenges. The 5G LTE communication system is a promising solution to provide a high user experience in terms of the provided speed, amount of data, and cost. However, and due to its complexity, the technology of LTE needs some improvement in terms of resource management and optimization. With the aid of AI, these two challenges can be overcome. In this paper, the AI represented by improved Q-learning algorithm with the Self-Organizing Network (SON) concept in LTE will be used to manage and optimize Handover (HO) parameters and process in the system. The ns-3 simulator result shows that AI managed to improve and optimize the LTE system performance.

A novel BCS code in a downlink LTE system over an LTE-MIMO channel

In general, a concatenated RS/BCH code consists of an outer RS code and an inner BCH code with separation by an interleaver. We create a novel BCS code using a new methodology by combining an outer BCH code with an inner RS code appended by an interleaver to randomize burst errors and help the RS code in correcting the errors. Generally, BCH codes handle binary data, whereas RS codes handle non-binary data. Hence, RS (7, 1) inner code is proposed to achieve compatibility with BCH (15, 5) outer codes and ultimately create a novel BCS code to handle binary data. The proposed BCS code is compared with familiar concatenated RS/BCH codes and single codes (RS and BCH) for BPSK and QPSK modulation schemes. Results show the downlink LTE system performance using the proposed BCS code is significantly better than the uncoded LTE system and single codes (RS and BCH). Moreover, the proposed BCS code also outperforms familiar concatenated RS/BCH codes for both schemes. In contrast, the system performance is improved further when the number of antennas in the MIMO channel is increased from $$2 \times 2$$ to $$4 \times 4$$ . Therefore, the proposed BCS code can be considered a stronger code with high reliability in wireless communication systems.

Comparison of Performance of Packet Scheduling Algorithms in LTE-A HetNets

The concept of usage of heterogeneous networks (HetNets) is about improving the LTE system performance by increasing the capacity and coverage of the Macro cell. In this paper, a performance comparison of various packet scheduling algorithms such as Proportional Fair, Maximum Largest Weighted Delay First and Exponential/Proportional Fair is studied in detail in the HetNets environment. The key performance indicators such as throughput, packet loss ratio, delay and fairness are considered to judge the performance of the scheduling algorithms. Various strategies such as increasing the number of Pico cells in the cell edge were used in the simulation for the performance evaluation study. The results achieved through various simulations show that adding Pico cells to the existing Macros enhances the overall system performance in addition to the various scheduling algorithms implemented in Macros. For reader’s convenience, various types of graphs have been used to represent the simulation results to better understand the performance metrics of various scheduling algorithms. Simulation results shows that overall system gain has increased because of adding Picos and thereby providing better coverage in the cell edge areas and thereby increasing the capacity of the network to provide better quality of service.

Location Awareness Impact on Long Term Evolution (LTE) System

Packet scheduling algorithms play an important role in determining throughput performance of LTE system. A stationary user with poor CQI (channel quality indicator) has smaller throughput and present scheduling algorithms are unable to address this issue. In this paper, a new scheduler technique is proposed which enhances throughput and fairness in LTE system for stationary as well as mobile users. This paper takes up preexisting scheduling algorithms and modifies them to schedule users according to a different criterion like fairness and Channel Quality Indicator. A hybrid of Round Robin and Best CQI techniques has been proposed for scheduling of the users which produces increased throughput for different SNR values simulated against Pedestrian and Vehicular moving models. The proposed model is very effective for stationary users, increasing throughput up to 500% and has been verified through MATLAB simulations.

Potential of dynamic spectrum allocation in LTE macro networks

Abstract. In recent years Mobile Network Operators (MNOs) worldwide are extensively deploying LTE networks in different spectrum bands and utilising different bandwidth configurations. Initially, the deployment is coverage oriented with macro cells using the lower LTE spectrum bands. As the offered traffic (i.e. the requested traffic from the users) increases the LTE deployment evolves with macro cells expanded with additional capacity boosting LTE carriers in higher frequency bands complemented with micro or small cells in traffic hotspot areas. For MNOs it is crucial to use the LTE spectrum assets, as well as the installed network infrastructure, in the most cost efficient way. The dynamic spectrum allocation (DSA) aims at (de)activating the available LTE frequency carriers according to the temporal and spatial traffic variations in order to increase the overall LTE system performance in terms of total network capacity by reducing the interference. This paper evaluates the DSA potential of achieving the envisaged performance improvement and identifying in which system and traffic conditions the DSA should be deployed. A self-optimised network (SON) DSA algorithm is also proposed and evaluated. The evaluations have been carried out in a hexagonal and a realistic site-specific urban macro layout assuming a central traffic hotspot area surrounded with an area of lower traffic with a total size of approximately 8 × 8 km2. The results show that up to 47 % and up to 40 % possible DSA gains are achievable with regards to the carried system load (i.e. used resources) for homogenous traffic distribution with hexagonal layout and for realistic site-specific urban macro layout, respectively. The SON DSA algorithm evaluation in a realistic site-specific urban macro cell deployment scenario including realistic non-uniform spatial traffic distribution shows insignificant cell throughput (i.e. served traffic) performance gains. Nevertheless, in the SON DSA investigations, a gain of up to 25 % has been observed when analysing the resource utilisation in the non-hotspot cells.

The Research on Reducing PAPR of the LTE Systems

MIMO-OFDM is one of the core technologies of 4G in the future, but the problem of high Peak—to—Average Power Ratio (PAPR) of LTE systems remains as one of the main obstacles that limit the application of OFDM. A method of space-frequency rotation and inversion has been proposed. According to the results of the Simulation, suppresses the smaller loss of PAPR performance, to improve the performance of LTE system.

The Effect of HARQ Procedure on the Performance of LTE System

The Effect of HARQ Procedure on the Performance of LTE System

Impact of base station antenna height and antenna tilt on performance of LTE systems

Impact of base station antenna height and antenna tilt on performance of LTE systems

Effcient High Throughput Algorithm of MIMO LTE Network

in order to improve the performance of lte system using mimo technology, we proposed an algorithm for lte mimo system based on the transmitting time delay. This algorithm can improve the throughput of mimo lte system. One access point can support more clients at the same time by using this method. A two antennas' base station may support 3 users simultaneously by using this algorithm to access the lte network. Moreover, it is easer for lte network to select pairing users for v-mimo system.

Research on a High Effective Algorithm of PRACH Baseband Signal in TD-LTE System

Random Access Procedure is a bridge between idle mode and connection mode in LTE system, and the algorithm of PRACH baseband signal we use will influence the performance of LTE system. A kind of High effective algorithm of PRACH baseband signal is introduced in this paper based on the research and analysis on the present PRACH baseband generation algorithm .By comparing and simulation, we find the algorithm introduced in this paper is feasible and effective. And this algorithm has been used in the RF conformance test system in LTE system.

System-level simulation methodology and platform for mobile cellular systems

System-level simulation has been widely used to evaluate the comprehensive performance of different mobile cellular systems. System-level simulation methodologies for different systems have been discussed by different organizations and institutions. However, the framework for a unified simulation methodology and platform has not been established. In this article, we propose a general unified simulation methodology for different cellular systems. Both the design of the simulation structure and the establishment of the simulation platform are studied. Meanwhile, the unified modeling and the realization of various modules related to the system-level simulation are presented. The proposed unified simulation methodology and the general simulation platform can be used to evaluate the performance of multiple mobile communication systems fairly. Finally, the overall performance of LTE and Mobile WiMAX systems is evaluated through the proposed framework. The key simulation results for both Full Buffer and VoIP traffics are presented and discussed. It is shown that the LTE system exhibits better performance than Mobile WiMAX.