Muhamad Asvial

Non-GEO Satellite Constellation Design with Satellite Diversity Using Genetic Algorithm

The paper describes optimization Non-GEO satellite constellation design with satellite diversity using genetic algorithm. This algorithm is called as genetic satellite constellation algorithm. A rank fitness assignment method of multiobjective optimization is proposed to capture a number of solutions simultaneously. The non-dominated in GA’s is sorted to find the multiple Pareto optimal points. The genetic satellite constellation algorithm is investigated to produce the optimum satellite constellation design with the minimum number of satellites while minimizing the maximum orbit’s altitude, to minimize the angle shift between satellites, to maximize the angle between planes and the inclination angle with satellite diversity. Illustrative results of satellite constellation components and dual satellite diversity statistics for LEO and MEO constellation are presented. The simulation results are compared to ICO for MEO constellation and to Globalstar for LEO constellation. Using genetic algorithm, satellite constellation design can be achieved the visibility of dual satellite diversity statistics whilst reducing the total number of satellites. Genetic algorithm is a robust method ideally suited for satellite constellation design.

Uplink resource allocation algorithms with fractional power control as power constraints for OFDMA system

In this paper, two algorithms in resource allocation with fractional power control scheme are proposed and evaluated. In these algorithms, we joint chunk allocation and unequal power allocation in one chunk by considering fractional power control scheme as power constraint on each user to improve the sum of spectral efficiency of users and fairness among users. In order to evaluate our proposed algorithms, we compare the performances of our proposed algorithms with those of the previous algorithms with fractional power control scheme as power constraint in each user. From the simulation results are shown that our proposed algorithms can improve the sum of spectral efficiency and fairness among users in macrocell urban and suburban condition.

Impact of fiber effective core area on transmission performance of various data rates over 390 km repeaterless bidirectional Raman span

Kerr nonlinear signal distortion and optical signal to noise ratio degradation are two major limiting factors on repeaterless bidirectional Raman amplified ultra-long span system. Both of these limiting factors are affected by the size of the fiber effective core area. The impact of fiber effective core area to Raman amplification gain, Kerr nonlinear signal distortion, Raman amplifier induced noise and optical signal to noise ratio are analytically investigated. Performance characteristics of various transmission data rate of differential phase modulated signal over 390 Km transmission distance of different effective core area fibers are examined. Raman analytical model and transmission simulation model show the advantage of large effective area fiber on reducing both limiting factors and enhance transmission performance.

Fiber effective core area impact on reducing nonlinear distortion and Raman noise of 42.7 Gb/s RZ-DPSK over 360 km bidirectional Raman span

The propagation model of repeaterless ultra-long span transmission system using bidirectional Raman amplifier is presented. General formulation of Raman gain, optical signal power, nonlinear phase shift, and optical signal to noise ratio as a function of fiber effective core area are analytically investigated. Numerical analysis results demonstrate the advantage of large effective core area on reducing nonlinear phase shift and Raman noise that lead to the enhancement of transmission performance. An application model based on computer simulation on repeaterless single transmission span over 360 Km propagation distance of 42.7 Gb/s RZ-DPSK modulated signal is examined. Computer simulation result demonstrates transmission performance of large effective core area fiber is better than small effective core area fiber that exactly matches to numerical analysis prediction.

Characterizing Nanoscale Transient Communication

We consider the novel paradigm of nanoscale transient communication (NTC), where certain components of the small-scale communication link are physically transient. As such, the transmitter and the receiver may change their properties over a prescribed lifespan due to their time-varying structures. The NTC systems may find important applications in the biomedical, environmental, and military fields, where system degradability allows for benign integration into life and environment. In this paper, we analyze the NTC systems from the channel-modeling and capacity-analysis perspectives and focus on the stochastically meaningful slow transience scenario, where the coherence time of degeneration Td is much longer than the coding delay Tc. We first develop novel and parsimonious models to characterize the NTC channels, where three types of physical layers are considered: electromagnetism-based terahertz (THz) communication, diffusion-based molecular communication (DMC), and nanobots-assisted touchable communication (TouchCom). We then revisit the classical performance measure of ε-outage channel capacity and take a fresh look at its formulations in the NTC context. Next, we present the notion of capacity degeneration profile (CDP), which describes the reduction of channel capacity with respect to the degeneration time. Finally, we provide numerical examples to demonstrate the features of CDP. To the best of our knowledge, the current work represents a first attempt to systematically evaluate the quality of nanoscale communication systems deteriorating with time.

Decision-based link scheduling approximation algorithm with SINR relaxation for wireless mesh network

The crucial issue in the design of resource allocation algorithms for wireless mesh network is computational complexity. A high capacity algorithm with low computational complexity is desired, especially for dynamic topology adaptation in mobile mesh networks and also for the issue of low energy consumption. This paper proposes a new approach in the designing of a low complexity spatial time division multiple access link scheduling algorithm for wireless mesh network. In this paper, link scheduling is considered as a decision-making problem. This approach is contrary to physical interference model that requires SINR evaluation in global network. We propose the mesh coverage probability as a new performance metric in the design of mesh link scheduling algorithm. Based on this approach, we provide the tradeoff between spatial reuse and mesh coverage probability, which can be used as a benchmark in the design of scheduling algorithms for wireless mesh network.

The forecasting model of 4G LTE implementation in Indonesia

Forecasting is an important step before the market deployment of upcoming 4G mobile technologies, i.e. LTE release 8 and release 10. A forecasting model working on the basis of Gompertz curve has been developed. Scenarios of rapid, moderate, and slow growth has been simulated by taking the case of Indonesia, in which the LTE frequency bands were assumed to be 1800 MHz and 2300 MHz. The number of LTE transceiver sites development depends on the MIMO configuration of the chosen LTE technical specifications. It is found that moderate growth scenario has the stable and controllable growth with its rate below 10%. This scenario should be enforced with LTE commonality for regions throughout the country. This scenario could be viewed as the most reasonable way to implement LTE in Indonesia.

STDMA based link scheduling algorithm evaluation for wireless mesh network

Recent developments in the various researches suggests that the mechanisms and algorithms in resource allocation is widely seen as a major new opportunity to improve the wireless networks performance. In the wireless mesh network which is now seen as a potential topology candidate in future networks, spatial reuse exploitation in scheduling is one solution to extend network capacity. This paper provides the evaluation of the performance of the scheduling algorithm in a mesh network based on time division multiple access method by spatial reuse exploitation, in comparison with another basic time division multiple access method. This paper was used as a basis to examine the possibility of developing a wireless mesh network performance through the mechanism of resource allocation, in WiMAX case.

Design and analysis of anti spamming SMS to prevent criminal deception and billing froud: Case Telkom Flexi

For cellular and fixed wireless users, SMS service has been the main needs after Voice. The fast growth of SMS users especially in Telkom Flexi, in one side has created one problem for operator, that is the increasing number of criminal deception via SMS. Besides using the limited number of operator signalling canals, the criminal deception using the post-paid number will effect directly to billing fraud. This is a problem at SMSC, as SMS Center to provide the features with additional security system such as anti spamming that performs parsing, checking, and blocking on the said SMS spamming. The objective, application design, application making, analysis and evaluation on the anti spamming effect will be described in detail in this paper. It is hoped that this anti spamming implementation can decrease the numbers of the SMS criminal deception and SMS billing fraud in Telkom Flexi.

The IoT-based Transition Strategy towards 5G

After the 5G standard is officially established, it is expected that 5G will be commercially deployed to the market within two to five years. However, problems may arise when mobile network operators start shifting their infrastructure to such a new technology. The main causes for concern would be financial-related issues, since the deployment of the 5G network requires a huge investment at a time when the level of market adoption is still uncertain. For that reason, mobile operators should explore technological opportunities to ensure the transition from 4G to 5G would bring no harm to their companys financial condition. This paper presents an explanatory review of the use of the Internet of Things (IoT) as the basis of a transition strategy towards the implementation of 5G. The 5G vision implies that 5G would not only focus on increasing high speed data but should also involve facilitating mission critical communications, as well as Massive Machine Type Communications (MMTC). Hence, mobile network operators can start deploying the IoT network immediately and can operate on the technical path towards the establishment of real 5Gs MTTC. Then, the two remaining 5G scenarios can be slowly introduced afterwards.