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"The book briefs you on energy propagation around and into the body and how to estimate performance of on-body wireless links, and then dives into the nuts-and-bolts of designing antenna systems that deliver the goods. It covers on-body communication channels at microwave frequency bands and at low frequency bands, as well as ultra wideband systems for WPANs and WBANs. You get details on body-centric UWB antennas and channels, as well as advances in wearable mobile, EBG, and ?smart fabric? antennas for cellular and WLAN communications. Chapters on telemedicine applications, such as remote diagnoses, and implantable medical devices cover crucial propagation issues and other obstacles that need to be addressed. Rounding out the coverage is a section on antenna design for body-sensor networks and their emerging military and space applications. Packed with hands-on guidance from noted experts, this volume will be indispensable for your efforts in designing and improving body-centric communication systems. (Publisher)"

"Seiring dengan perkembangan teknologi seluler maka teknologi satelit merupakan bagian yang penting masuk di dalamnya. Terlebih lagi dengan akan diluncurkannya Quasi Zenith satellite yang melewati beberapa negara di Asia dan Australia diantaranya adalah Indonesia. Dengan satelit ini kinerja komunikasi seluler menjadi lebih baik.Untuk Indonesia terutama di sekitar Jakarta maka untuk mengakses satelit tersebut maka antena harus memiliki elevasi 45°. Selain itu harus dapat beroperasi pada 2.6 GHz (2.605 GHz - 2.63 GHz).Dalam penelitian ini dibuat antena mikrostrip 2x2 yang tersusun secara planar dengan bentuk patch segitiga sama sisi. Dari hasil pengukuran terbukti bahwa antena memiliki elevasi pola radiasi 45° pada frekuensi resonansinya. Sedangkan karakteristik penting lainnya adalah bandwidth impedansinya yang lebar 10.4% atau 277.11 MHz (2.80211 GHz - 2.525 GHz), sehingga dapat dipergunakan untuk aplikasi wireless communication pada Quasi Zenith Satellite.Hal tersebut diatas diperoleh dengan mengatur jarak antar elemen antena dan mengatur pergeseran fasa. Di mana pergeseran fasa dicapai dengan cara mengatur perbedaan panjang padapencatuan. Antena yang tersusun secara planar ini memiliki ukuran substrat 20 cm x 20 cm. Adapun substrat tersebut memiliki permitivitas relatifnya sebesar 2.2 dengan ketebalan substrat 0.8 mm.

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With development of Celluler technology so satellite technology is important for that. Moreover Quasi Zenith satellite will be launched and will pass some country in Asia and Australia, one of them is Indonesia. By this satellite so celluler communication performance is getting better.

For Indonesian area especially Jakarta, to access that satellite, antenna must has Radiation Pattern elevation about 45°. While the system must be operated on 2 GHz (2.605 GHz - 2.63 GHz).

In this Research, has made microstrip antenna 2x2 planar array with equilateral triangular patch. From measurement result are proven that antenna has Radiation Pattern elevation about 45° at resonance frequency. Meanwhile, another important characteristic is impedance bandwidth 10.4% or 277.11 MHz (2.80211 GHz - 2.525 GHz), so it can be used for application of wireless communication in Quasi Zenith Satellite.

It can be reached by controlling spacing patch element and progressive phase. When progressive phase can be reached by controlling difference of length of feeding. This antenna substrat has dimension 20 cm x 20 cm, with relative permitivity 2.2 and thick of substrat is 0.8 mm."

"Wireless and mobile communications is a fast growing area and has an enormous impact on almost every aspect of our daily lives. This new book examines integrated circuits, systems and transceivers for wireless and mobile communications. It covers the most recent developments in key RF, IF, analogue, mixed-signal components and single-chip transceivers in CMOS technology, a preferred technology for system on chip design. The book takes a top-down approach from wireless communications systems, mobile terminals/transceivers, to constituent blocks, and covers the whole range of analogue, mixed signal, baseband, IT and RF circuits in a systematic way."

"Tantangan terbesar pengembangan layanan komunikasi wireless adalah frequency-bandwidth yang terbatas dan mahal. Karena itu dibutuhkan tidak hanya sistem berkecepatan tinggi saja tetapi juga sistem yang mampu menggunakan bandwidth secara efisien. Walaupun sulit membangun sistem berkecepatan tinggi dengan error-rate rendah, namun pada tulisan ini diperkenalkan sebuah sistem closed-loop MIMO (Multiple-Input Multiple-Output) menggunakan detektor ML (Maximum Likelihood) sederhana untuk mengoptimalkan kapasitas dan meningkatkan performansi sistem. Pemakaian MIMO menjadi spesial karena kemampuannya dalam meningkatkan kapasitas dan performansi tanpa menambah frequency-spectral. Skenario besar konsep ini didapat dari keuntungan pemakaian matriks transformasi yang mampu mengalokasikan daya sinyal-sinyal transmisi sesuai dengan kondisi kanal. Selain itu, perkalian matriks ini dapat membentuk kanal-kanal singular yang paralel. Sehingga dengan zero inter-channels correlation, maka detektor ML dapat dirancang guna meningkatkan performansi. Pada akhirnya, simulasi komputer memberikan validasi bahwa pada SNR (Signal-to-Noise Ratio) 0 dB dapat dicapai kapasitas optimal sampai 1 bps/Hz dan SER sampai dengan 0,2 lebih baik dari sistem opened-loop MIMO.

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In order to support providing broadband wireless communication services against limited and expensive frequency bandwidth, we have to develop a bandwidth efficient system. Therefore, in this paper we propose a closed-loop MIMO (Multiple-Input-Multiple-Output) system using ML (Maximum Likelihood) detector to optimize capacity and to increase system performance. What is especially exciting about the benefits offered by MIMO is that a high capacity and performance can be attained without additional frequency-spectral resource.

The grand scenario of this concept is the attained advantages of transformation matrices having capability to allocate transmitted signals power suit to the channel. Furthermore, product of these matrices forms parallel singular channels. Due to zero inter-channels correlation, thus we can design ML detector to increase the system performance. Finally, computer simulations validates that at 0 dB SNR our system can reach optimal capacity up to 1 bps/Hz and SER up to 0.2 higher than opened-loop MIMO."

"This book is a collection of papers from international experts presented at International Conference on NextGen Electronic Technologies (ICNETS2-2016). ICNETS2 encompassed six symposia covering all aspects of electronics and communications domains, including relevant nano/micro materials and devices. Presenting recent research on wireless communication networks and Internet of Things, the book will prove useful to researchers, professionals and students working in the core areas of electronics and their applications, especially in signal processing, embedded systems and networking."

"Channel estimation memiliki definisi untuk memperkirakan koefisien filter melalui sinyal yang diterima dan informasi lain yang dikenal. Ada beberapa metode channel estimation yang dapat diguanakan seperti minimum mean square error, least square, zero-force, maximum likelihood. Dalam penelitian ini, least square dan zero-force akan dibahas lebih lanjut. Kedua jenis ini dikenal umum sebagai jenis yang paling sederhana dan paling mudah untuk diterapkan di dalam komunikasi nirkabel. Meskipun metode lain seperti minimum mean square error atau maximum likelihood telah dikenal secara luas untuk memperkirakan kanal, metode tersebut terbukti sangat kompleks untuk diimplementasikan.Penelitian ini bertujuan untuk memahami efek dan membandingkan kinerja channel estimation dengan menggunakan kapasitas multi antenna seperti Single-Input Single Output (SISO), Multiple-Input Single-Output (MISO), Single-Input Multiple-Output (SIMO) dan Multiple-Input Multiple-Output (MIMO). Least square dan metode estimasi zero-force telah digunakan dengan memakai modulasi Binary Phase Shift Keying (BPSK), hal ini dikarenakan BPSK adalah metode phase shift keying yang paling sederhana untuk di implementasikan di dalam penelitian ini. Pertama-tama, segala parameter perlu dikonfigurasi terlebih dahulu untuk digunakan di dalam simulasi. Kemudian, data dalam sistem pilot dikirim ke penerima menggunakan modulasi BPSK di setiap sistem multi antenna dengan menggunakan saluran nirkabel yang berbeda. Lalu, Alamouti encoder dieksekusi khusus untuk sistem MIMO dan MISO. Setelah itu, least square dan zero-force diterapkan dan tingkat kesalahan bit atau dengan nama lain bit error rate (BER) dapat dicapai dengan menyamakan sinyal yang ditransmisikan. Kemudian, analisa hasil data dengan membandingkan kinerja least square dan zero-force dapat dicapai. Pada akhirnya, hasil yang telah ditemukan menunjukkan bahwa least square melakukan performa lebih baik daripada metode estimasi zero force yang berlaku pada kinerja tingkat kesalahan bit dengan sinyal terhadap noise atau dengan nama lain signal to noise ratio (SNR).

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Channel estimation has a definition to estimate the filter coefficient through received signal and other known information. There are many methods that channel estimation can be used such as minimum mean square error, least square, zero-force, maximum likelihood. In this research, least square and zero force will be discussed further. These two types are commonly known as the simplest and easiest type to implement in the wireless communication. Even though other methods like minimum mean square error or maximum likelihood have been widely known to estimate channel, such methods are proven very complex to implement.

The aimed of this research is to understand the effect and compare the performance of the channel estimation method with the capacity of multiple antennas such as Single-Input Single-Output (SISO), Multiple-Input Single-Output (MISO), Single-Input Multiple-Output (SIMO) and Multiple-Input Multiple-Output (MIMO). Least square and zero force estimation method were being used with BPSK modulation, this is due to BPSK is the simplest phase shift keying.

First, the parameters need to be configured in simulation software. Then, the data within pilots system transmitted to receiver using BPSK modulation in each of the wireless antenna systems with different wireless channels. Space time block coding of Alamouti encoder were executed for MIMO and MISO system. After that, least square and zero force method were implemented and bit error rate (BER) performance can be achieved by equalizing the transmitted signal. Analysing the result by comparing the performance of least square and zero force were accomplished.

In the recent result, it was shown that the least square performs better than zero force estimation method for the performance of bit error rate with signal to noise ratio."