Modified Greedy Physical Link Scheduling Algorithm for Improving Wireless Mesh Network Performance

The algorithm to allocate mesh active link to radio resource timeslot in wireless mesh network (WMN) is investigated. This paper proposes the novel method to allocate multiple links in one timeslot for improving the wireless mesh network throughput via spatial time division multiple access (STDMA) protocol. The throughput improvement is obtained by modifying greedy based algorithm that is widely known as a low complexity algorithm. We propose and investigate new parameters in the greedy based algorithm that can be used as scheduling control parameters, i.e. interference weight, scheduling weight, and the sum of link’s degree. Simulation results indicate that this approximation increases network performance in throughput and length of scheduling performance closed to the upper bound performance that is achieved by the algorithm that uses the physical interference model.

Analisis Koeksistensi Jaringan LTE Non Lisensi dan Wi-Fi Pada Frekuensi 5GHz

Untuk memenuhi permintaan kebutuhan trafik layanan internet yang akan terjadi pada 2020, penggunaan spektrum harus dilakukan secara maksimal. Pemanfaatan spektrum frekuensi non-lisensi oleh teknologi LTE-Unlicensed atau LTE Non-Lisensi dapat memenuhi permintaan kebutuhan trafik. Tetapi spektrum frekuensi non-lisensi sudah terlebih dahulu digunakan oleh teknologi Wi-Fi, maka teknologi LTE Non-Lisensi harus dapat beradapatasi dan berkoeksistensi dengan Wi-Fi. Penelitian ini akan membahas jarak minimum yang dibutuhkan oleh eNodeB LTE Non-Lisensi dan Access Point Wi-Fi agar kedua teknologi ini dapat berkoeksistensi dengan kondisi indoor LOS dan NLOS serta outdoor LOS dan NLOS. Koeksistensi ditinjau dari nilai ACIR antara kedua teknologi tersebut. Berdasarkan hasil penelitian, jarak minimum untuk indoor adalah 16m-35m dengan kondisi LOS dan outdoor adalah 51m-199m dengan kondisi LOS. Nilai SINR threshold adalah 22dB untuk LTE Non-Lisensi dan 19,7dB untuk Wi-Fi. Dari hasil simulasi didapatkan nilai rata-rata CINR untuk outdoor adalah 15dB sedangkan untuk indoor nilai SIR rata-rata adalah 0,62dB.By the 2020 the traffic internet demand will be increasing, so that the utilization of spectrum frequency should be maximize and use wisely. LTE-U which is using unlicensed spectrum frequency may be option to fulfil the demand of the internet traffic. Unfortunately it has to adapt and coexistence with Wi-Fi which already exist in unlicensed spectrum frequency. In this research, will talk about the minimum distance needed so that LTE-U eNodeB and Wi-Fi can be coexistence in indoor and outdoor deployment LOS and NLOS condition. The coexistence analyze in ACIR value. The result, minimum distance needed is in range 16 m-35 m for indoor deployment. In the other hand 51 m-199 m for outdoor deployment. With software simulation in 51 m distance the mean CINR value is 15 dB, and for 16 m distance the mean SIR value is 0.62 dB

Energy efficient resources allocations for wireless communication systems

The energy consumption level of the telecommunication process has become a new consideration in resource management scheme. It is becoming a new parameter in the resource management scheme besides throughput, spectral efficiency, and fairness. This work proposes a power control scheme and user grouping method to keep the rational energy consumption level of the resource management scheme. Inverse water-filling power allocation is a power allocation scheme that optimizes the energy efficiency by giving the power to the user which have good channel conditions. The user grouping method becomes the solution for carrier aggregation (CA) scheme that prevents edge cell user get the resources from the high-frequency carrier. This can prevent energy wastage in the transmission process. This power control scheme and user grouping method can optimize the spectral and energy efficiency without increasing the time complexity of the system

IEEE 802.11ah Network Planning for IoT Smart Meter Application: Case Study in Bandung Area

The growth of Wireless Fidelity (WiFi) technology is so rapid and popular. The technology most widely used for WiFi services is the IEEE 802.11 family of standards. To support the Internet of Things (IoT) era, 802.11ah standard technology has developed, and the standard is intended to provide a low-cost mode of operation, with a wider coverage area, and can support thousands of devices per cell. This paper discusses IEEE 802.11ah Standard Network Planning for the Internet of Things Application (Case Study: Smart Meter Using WiFi.id Network in Bandung), to improve network quality in terms of coverage and capacity to improve the efficiency of the WiFi network and so that it can supports the Internet of Things (IoT) service. Network planning using 802.11ah for the internet of things application with a smart meter case study using the WiFi.id network has been successfully carried out. To cover the entire area of Bandung, 23 sites are required. In the capacity, the Tx slots needed to cover possible smart meters for each site are only 9 tx slots out of a total of 100 tx slots.

Performance Analysis of Multiple Input Multiple Output (MIMO) Multi-Carrier Code-Division Multiple Access (MC-CDMA) Combined with Quasi-Orthogonal Space Time Block Coding (QO-STBC) in Rayleigh Fading Channel

The need for a communication system with a higher data rate and mobility grows along with information and communication technology development. Combining MC-CDMA with the MIMO system and supporting the system with a good transmit diversity technique is a promising idea to provide the needed communication system, especially in high mobility conditions. MC-CDMA can support ubiquitous communications without affecting the achievable BER and is more capable of high-speed mobility. It integrates the benefit of both OFDM and CDMA. On the other hand, QO-STBC increases the bit rate without using additional bandwidth to transmit diversity in the MIMO system. So, this study proposed a system combining the MIMO MC-CDMA system with QO-STBC. The proposed system is investigated under high mobility conditions to see the system's performance. The simulation results show that our system performs better than the MC-CDMA STBC system and the QOSTBC system but not better than the MC-CDMA multilevel coding scheme. To reach the value of BER 10−3, MC-CDMA multilevel Coding requires less power, around 5 dB, than the proposed system

Perhitungan Jarak Paparan Radiasi Base Transceiver Station pada Frekuensi 900 MHz, 1800 MHz, dan 2100 MHz Berdasarkan Standar World Health Organization

Abstrak Teknologi telekomunikasi yang banyak dimanfaatkan untuk berkomunikasi di era internet saat ini adalah teknologi Long Term Evolution (LTE). Dalam menyelenggarakan layanan LTE, diperlukan suatu penghubung antara jaringan akses dengan core yang biasa dikenal dengan istilah backhaul. Salah satu backhaul yang biasa digunakan untuk menyambungkan suatu link komunikasi ini adalah backhaul microwave. Penerapan dari link microwave ini biasa digunakan untuk komunikasi line of sight (LOS). Oleh karena itu, perencanaan link microwave ini tidak mudah karena akan ada banyak faktor yang mempengaruhi link komunikasi ini, diantaranya: penghalang, fading, atenuasi, noise maupun jarak. Pada penelitian ini akan dilakukan perencanaan link microwave antara Kota Semarang dengan Kota Magelang dengan 3 skenario. Skenario pertama dilakukan dengan komunikasi langsung singlehop, skenario kedua dengan memanfaatkan repeater aktif, dan skenario ketiga dilakukan dengan repeater pasif. Hasil akhir menunjukan bahwa skenario yang paling sesuai untuk diimplementasi pada link microwave Semarang-Magelang ini adalah skenario kedua. Penggunaan repeater aktif yang memantulkan dan menguatkan sinyal site Tx menuju site Rx ini mampu menjadi solusi untuk lintasan link yang terdapat obstacle dan berjarak sangat jauh. Penggunaan skenario 2 dalam penelitian ini menunjukan kekuatan signal di site Semarang dan Magelang adalah masing-masing -54,67 dBm dan -48,66 dBm. Kekuatan sinyal ini berada di atas Rx threshold pada kedua site, yaitu -67,50 dBm.  Abstract Exposure to electromagnetic wave radiation from Base Transceiver Station can cause a negative impact on human health, can cause headache, brain tumors, cancer, and fetal disorders in pregnant women. In addition, to minimize the adverse effects of electromagnetic radiation exposure on the human body, the construction of Base Transceiver Station must comply with regulations regarding the safe distance of Base Transceiver Station from residential areas, such as electromagnetic field regulations that have been implemented in South Korea. From the results of mathematical calculations in accordance with World Heatlh Organization standards and electromagnetic field regulations in South Korea, it can be seen that the minimum safe distance of Base Transceiver Station to residential areas is influenced by the frequency, gain, and power of the Base Transceiver Station. This can be seen in the results od the classification of the radiation zone base on electric fields, with the use of 30 dBm power and 20 dBi gain with a frequency of 900 MHz for the Class 2 zone distance, which is 14.317 m from BTS, for 1800 MHz frequency is 7.668 m from BTS, and for 2100 MHz frequency is 2.702 m from BTS. As for the use of 43 dBm power and 20 dBi gain with a frequency of 900 MHz for the Class 2 zone distance, which is 39.86 m from BTS, for the 1800 MHz frequency is 19.939 m from BTS, and for 2100 MHz frequency is 13.638 m from the BTS

Enhancement of Twice Quasi Orthogonal Space Time Block Coded (QOSTBC) Performance System with Zero Forcing EVCM Decoder

In today’s modern telecommunications systems, makes the number of studies and development of multiple antennas and multiple-input multiple-output (MIMO) systems to achieve high reliability and low complexity. One attractive approach to improve that performance is using technique transmit diversity which is spacetime block coding and receiver diversity i.e. zero forcing EVCM (ZF EVCM). Although some earlier MIMO standards were develop some space-time codes like (O-STBC)and (Q-OSTBC) to provide high reliability but they are limited able to achieve orthogonality. In this research will be proposed a MIMO system scheme which is an improvement of QOSTBC that used a transmission diversity technique. This improvement from QOSTBC is Twice QOSTBC uses a provision in two codeword matrices to be sent are arranged diagonally so as to have higher levels of orthogonality. In this case Twice QOSTBC highly structured (4x1) can be replaced as an equivalent EVCM channel H. The proposed Twice-QOSTBC’s results outperform other QOSTBC techniques with a difference around 3 dB for single-input multi-input (MISO) input configuration at 10-6 BER and receiver ZF EVCM has a very similar structure as the code matrix S of the underlying Twice QSTBC which can eliminates the system complexity

Simple Iterative Channel Coding and Modulation for Harbor Wireless Communications

Monitoring systems at the harbor require a simple communication technique to save battery energy, strong   in error correction, and suitable to the harbor channel model, of which the channel is predicted to have more number   of path. This paper proposes (i) a harbor channel model and (ii) a simple iterative repetition coding for harbor     wireless communication of monitoring systems. The harbor channel model is derived using a series of computer simulations based on real-field harbor environmental parameters, while the proposed  iterative  channel  coding  is  based on the repetition codes assisted by a doped accumulator (ACC) with a doping technique. Channel coding and doping rates are designed using an Extrinsic Information Transfer (EXIT) chart and are evaluated using a series of computer simulations in terms of Bit Error Rate (BER) and Frame Error Rate (FER) performances with an outage performance as the theoretical baseline for comparison. Since the EXIT curve of the repetition codes has steep curve,  we use a non-Gray Quadrature Phase Shift Keying (QPSK) to achieve a better matching between the decoder and  the demapper of harbor channels. We found that the proposed simple repetition codes and non-Gray demapper provide excellent performances for harbor communications with a cliff of BER curve. The results of this paper are expected to contribute to the development of a reliable wireless communications for the harbor monitoring applications

Evaluasi Coded Random Access untuk Visible Light Communication pada Model Kanal Non-Line Of Sight

ABSTRAK Penggunaan Non-Orthogonal Multiple Access (NOMA) pada sistem komunikasi dapat memberi kebebasan bagi user untuk mengirimkan informasi secara bersamaan tanpa harus memperebutkan timeslot ataupun frekuensi. Coded Random Access (CRA) adalah salah satu bagian dari Coded Comain-NOMA (CDNOMA) yang menggunakan kode tanpa ortogonal untuk komunikasi uplink. Terinspirasi dari Additive Links On Line Hawaii Area (ALOHA), kami menggunakan metode Irregular Repetition Slotted ALOHA (IRSA) dengan tiga jumlah slot node dan sembilan degree distribution pada model kanal Line Of Sight (LOS) dan Non-LOS (NLOS). Kami menggunakan metrik pengukuran berupa throughput dan Packet Loss Ratio (PLR) untuk memperoleh hasil simulasi. Dari simulasi yang ekstensif, kami membuktikan bahwa IRSA stabil pada jumlah slot node yaitu 75, 150 dan 300 yang memperoleh throughput di sekitar 0.75 paket/slot. Kata kunci: Coded Random Access, Non-Orthogonal Multiple Access, Slotted ALOHA, Successive Interference Cancellation   ABSTRACT The use of Non-Orthogonal Multiple Access (NOMA) in communication systems can provide users the freedom to transmit information simultaneously without having to fight over timeslots or frequencies. Coded Random Access (CRA) is a part of Coded Domain-NOMA (CD-NOMA) that uses orthogonal code for uplink communication. Inspired by the Additive Links On Line Hawaii Area (ALOHA), we use the Irregular Repetition Slotted ALOHA (IRSA) method with three number of node slots and nine degree distributions on the Line Of Sight (LOS) and Non-LOS (NLOS) channel models. We use measurements in the form of throughput and Packet Loss Ratio (PLR) to obtain simulation results. From extensive simulations, we prove that IRSA is stable on a wide number of node slots of 75, 150 and 300 that acquire throughput in about 0.75 packets/slot. Keywords: Coded Random Access, Non-Orthogonal Multiple Access, Slotted ALOHA, Successive Interference Cancellatio

Analisis Performansi Multi User Detection pada Kanal NLOS untuk Sistem NOMA-VLC

ABSTRAKNon-orthogonal multiple access (NOMA), mulai diteliti untuk dapat digunakan sebagai teknik multiple access yang efektif pada jaringan 5G karena teknik ini dapat menghemat bandwidth modulasi. Pada penelitian ini, NOMA diterapkan untuk sistem downlink Visible Light Communivation (VLC). Kami telah melakukan analisis performansi Multi-User Detection (MUD) pada kanal propagasi Non-Line of Sight (NLOS) dengan mempertimbangkan efek reflektor dan efek bayangan (shadowing). Kami juga mempertimbangkan teknik MUD yang digunakan pada penelitian ini yaitu Succesive Interference Cancellation (SIC). Setelah simulasi yang ekstensif, kami menemukan bahwa dengan penerapan SIC sebagai MUD pada sistem NOMA-VLC lebih baik dibandingkan dengan tanpa NOMA. Selain itu, kami juga memperoleh peningkatan data rate sebesar 72 %.Kata kunci: VLC, NOMA, NLOS, MUD, Optical Wireless Communication. ABSTRACTNon-orthogonal multiple access (NOMA), began to be studied to be used as an effective multiple access technique on 5G networks because this technique can save modulation bandwidth. In this research, NOMA is applied to the Visible Light Communivation (VLC) downlink system. We have performed a Multi-User Detection (MUD) performance analysis on Non-Line of Sight (NLOS) propagation channels by considering the reflector and shadowing effects. We also consider the MUD technique used in this study, namely Successive Interference Cancellation (SIC). After extensive simulations, we found that the application of SIC as MUD to the NOMA-VLC system is better than without NOMA. In addition, we also achieve an increase in data rate of 72%.Keywords: VLC, NOMA, NLOS, MUD, Optical Wireless Communication