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"This book provides a novel solution for existing challenges in wireless body sensor networks (WBAN) such as network lifetime, fault tolerant approaches, reliability, security, and privacy. The contributors first discuss emerging trends of WBAN in the present health care system. They then provide possible solutions to challenges inherent in WBANs. Finally, they discuss results in working environments. Topics include communication protocols of implanted, wearable and nano body sensor networks; energy harvesting methodologies and experimentation for WBAN; reliability analysis and fault tolerant architecture for WBAN; and handling network failure during critical duration. The contributors consist of researchers and practitioners in WBAN around the world."

"This SpringerBrief introduces the basics of wireless powered communication networks (WPCNs). In particular, the background and concept of WPCNs are briefly discussed. Moreover, this brief provides an extensive study of the recent developments in this area from an optimization perspective. Wireless powered communication network (WPCN) is a new network paradigm for IoT, where wireless devices (WDs) are powered by radio frequency (RF) based wireless power transfer (WPT) to eliminate the need for recharging or replacing the batteries manually and to prolong their lifetime.In this context, the brief also discusses some optimization problems for state-of-the-art scenarios of wireless powered communication networks.The target audiences for this SpringerBrief are researchers, engineers, and undergraduate and graduate-level students, who are studying or working in wireless powered communication networks and its performance optimization."

"This Springerbrief presents a deep reinforcement learning approach to wireless systems to improve system performance. Particularly, deep reinforcement learning approach is used in cache-enabled opportunistic interference alignment wireless networks and mobile social networks. Simulation results with different network parameters are presented to show the effectiveness of the proposed scheme.There is a phenomenal burst of research activities in artificial intelligence, deep reinforcement learning and wireless systems. Deep reinforcement learning has been successfully used to solve many practical problems. For example, Google DeepMind adopts this method on several artificial intelligent projects with big data (e.g., AlphaGo), and gets quite good results."

"Communications, Signal Processing, and Systems is a collection of contributions coming out of the International Conference on Communications, Signal Processing, and Systems (CSPS) held August 2012. This book provides the state-of-art developments of Communications, Signal Processing, and Systems, and their interactions in multidisciplinary fields, such as audio and acoustic signal processing. The book also examines Radar Systems, Chaos Systems, Visual Signal Processing and Communications and VLSI Systems and Applications. Written by experts and students in the fields of Communications, Signal Processing, and Systems."

"This book provides an overview of the latest research and development of new technologies for cognitive radio, mobile communications, and wireless networks. The contributors discuss the research and requirement analysis and initial standardization work towards 5G cellular systems and the capacity problems it presents. They show how cognitive radio, with the capability to flexibly adapt its parameters, has been proposed as the enabling technology for unlicensed secondary users to dynamically access the licensed spectrum owned by legacy primary users on a negotiated or an opportunistic basis. They go on to show how cognitive radio is now perceived in a much broader paradigm that will contribute to solve the resource allocation problem that 5G requirements raise. The chapters represent hand-selected expanded papers from EAI sponsored and hosted conferences such as the 12th EAI International Conference on Mobile and Ubiquitous Systems, the 11th EAI International Conference on Heterogeneous Networking for Quality, Reliability, Security and Robustness, the 10th International Conference on Cognitive Radio Oriented Wireless Networks, the 8th International Conference on Mobile Multimedia Communications, and the EAI International Conference on Software Defined Wireless Networks and Cognitive Technologies for IoT."

"Teknologi komunikasi tanpa kabel masa depan dituntut untuk mampu melayani aplikasi multimedia termasuk informasi suara dan data berkecepatan tinggi. CDMA adalah salah satu teknologi yang dapat diaplikasikan dan telah dibuktikan sebagai teknik akses jamak yang mampu untuk menyediakan berbagai macam kebutuhan layanan tersebut.Pada tesis ini akan dibahas analisa throughput dan kapasitas sistem multi sel dan multi kelas CDMA. Sistem multi sel dianalisa sampai dengan dua tier sedangkan sistem multi kelas dibagi menjadi 2 trafik yaitu kelas-1 untuk layanan suara dan kelas-2 untuk layanan data. Kinerja sistem dihasilkan dari perhitungan throughput untuk layanan kelas-2 dan perhitungan BER untuk layanan kelas-1. Analisa kapasitas dan throughput didasarkan pada pengaruh dari variasi kecepatan chip, kecepatan bit dan faktor aktivitas.Hasil analisa menunjukkan, dengan kecepatan chip yang lebih besar dapat memperbaiki BER yang dibutuhkan oleh tiap layanan informasi serta dapat meningkatkan kapasitas dan throughput sistem pada saat kondisi trafik padat. Sebaliknya, kecepatan bit yang lebih besar akan menurunkan kapasitas dan throughput total sistem. Semakin besar faktor aktivitas akan menaikkan throughput namun menurunkan kapasitas total sistem. Pengaruh interferensi pada sistem multi sel dan multi kelas dapat menurunkan throughput dan kapasitas total dari trafik informasi yang ditawarkan.

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The future technology of wireless technology of wireless communication system must be able to serve a multimedia application, included voice and high speed data information. DS-CDMA is one of communication technology which can used and have been proved as technique of multiple access that capable to provide this service requirement.In this thesis, analysis of throughput and capacity are proposed for multi cell and multi class CDMA system. System of multi cell analyzed until two tier and system of multi class divided two classes of traffic that are class-1 far voice and class-2 for data services. Performance measurement is obtained in respect of throughput for class-2 traffic and BER for class-1 traffic . Analysis of throughput and capacity according to the effect of variable quality of services, chip rate, bit rate and activity factor.The result show that with larger chip rate can maintain the required BER of each information and achieve the capacity and throughput in high traffic condition. Otherwise, with larger bit rate will decrease total throughput and capacity. With larger activity factor will decrease total capacity but can increase throughput of system. The effect of interference in multi cell and multi class system can decrease throughput and total capacity of offered information traffics."

"Konsep Orthogonal Frequency Division Multiplexing ( OFDM) adalah membagi aliran data input serial ke dalam sejumlah aliran data paralel dan mengirimkan aliran data paralel dengan rate rendah tersebut secara bersamaan. Salah satu keuntungan penggunaan OFDM dibandingkan dengan jenis modulasi lain adalah penggunaan lebar pita yang tersedia dengan lebih efisien.Simulasi dan analisa dilakukan terhadap performansi sistem OFDM pada beberapa mapper modulasi 16-my pada kondisi kanal AWGN dan kanal fading lambat. Jenis konstelasi yang digunakan adalah 16-QAM rektangular, 16-QAM star dan 16-PSK.Hasil pada kondisi kanal AWGN memperlihatkan bahwa sistem OFDM yang menggunakan 16-QAM rektangular memberikan performansi BER terbaik dibandingkan penggunaan 16-QAM star atau 16-PSK.Performansi OFDM pada kanal fading multipath dianalisa menggunakan respons impuls kanal statik. Hasil pada kedua model kanal fading multipath yang digunakan menunjukkan performansi yang relatif buruk. Algoritma forward error correction atau estimasi kanal perlu digunakan untuk mengurangi probabilitas kesalahan bit.Hasil akhir pada penggunaan kedua algoritma tersebut membuktikan bahwa pengaruh fading kanal multipath dapat dihilangkan sehingga meningkatkan performansi BER sistem OFDM.

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The concept of OFDM is to divide the serial input data stream into a number of parallel streams and to transmit these low-rate parallel streams simultaneously. One advantage of using OFDM compared to other types of modulation is better use of the available bandwidth.

The performance of the OFDM system under various 16-ary modulation mappers in AWGN and slowly fading channels are analyzed. It considers three candidate constellations : 16 rectangular-QAM, 16 star-QAM and 16-PSK.

The results for AWGN channel shows that the OFDM system using 16 rectangular-QAM gives the best BER performance compared to the same system using 16 star-QAM or 16-PSK mapper.

The performance of OFDM on multipath fading channels is analyzed using static channel impulse responses. The results of system in the two models of multipath fading channels indicate a relatively poor performance. Forward error-correcting or channel estimation algorithm is necessary to reduce the bit error probability.

The final results obtained after the use of both algorithms : convolutional coding and channel estimation, prove that fading effects can be removed, reducing almost totally the effects of the multipath channel."