30 research outputs found
Analisis Performansi Multi User Detection pada Kanal NLOS untuk Sistem NOMA-VLC
Get PDFABSTRAKNon-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
Enhancement of Twice Quasi Orthogonal Space Time Block Coded (QOSTBC) Performance System with Zero Forcing EVCM Decoder
No full textIn 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
Analisis Koeksistensi Jaringan LTE Non Lisensi dan Wi-Fi Pada Frekuensi 5GHz
Get PDFBy 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.</jats:p
Evaluasi Coded Random Access untuk Visible Light Communication pada Model Kanal Non-Line Of Sight
Get PDFABSTRAKPenggunaan 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 ABSTRACTThe 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
Frequency recommendation for long term evolution network implementation using simple multi attribute rating technique
Get PDFThe increasing demand for telecommunication services causes data traffic density. Therefore, in this research, the long-term evolution (LTE) network expansion was carried out using a choice of frequency bands of 700 MHz, 2100 MHz, and 2300 MHz. The analysis was carried out from the technical and economic aspects. Frequency band recommendations were obtained using the simple multi-attribute rating technique (SMART) method. This research was conducted using a case study of Semarang City. Based on the simulation results, the average of reference signal receive power (RSRP) values for frequency 700 MHz and 2300 MHz is in the very good range, while the frequency of 2100 MHz is in the good range. The signal to interference noise ratio (SINR) values for the three frequencies are in the normal category and the throughput values are in the very good category. The techno-economic calculations of the three frequencies, namely the value of internal rate of return (IRR), net present value (NPV), and payback period are included in the business category that is feasible to do. Based on the ranking results, the 700 MHz frequency is the most superior, both in terms of technical and economic aspects
Decision-based link scheduling approximation algorithm with SINR relaxation for wireless mesh network
No full textLow Density Parity Check Code (LDPC) for Enhancement of Visible Light Communication (VLC) Performance
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