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"Analisis throughput proposed an integrated system consisting of multicode - multicarrier code - division multiple - access (MC-MC-CDMA) with slotted aloha (S-Aloha) scheme with dual medium has been done, named MC-MC-CDMA S - ALOHA...."

"Pada sistem komunikasi bergerak, fading menyebabkan penurunan unjuk kerja. Unjuk kerja sistem dapat diperbaiki dengan menggunakan efek capture. Efek capture adalah dapat diterimanya suatu sinyal tanpa kesalahan pada receiver pada saat terdapat banyak sinyal yang dikirim secara simultan pada kanal. Dalam tesis ini dianalisa unjuk kerja metode akses slotted ALOHA-CDMA pada LEO dengan efek capture pada kanal ber-fading yang terdistribusi Rician. Unjuk kerja yang dianalisa meliputi probabilitas paket sukses, throughput dan delay akses kanal.Dari hasil perhitungan terlihat bahwa makin besar w (track makin uniform), probabilitas paket sukses slotted ALOHA-CDMA makin tinggi, throughput semakin besar dan delay kanal slotted ALOHA-CDMA makin kecil. Makin besar faktor Rician K dan makin banyak jumlah kode Nc probabilitas paket sukses dan throughput kanal slotted ALOHA-CDMA makin besar. Makin kecil rasio capture probabilitas paket sukses dan throughput kanal slotted ALOHA CDMA makin besar. Makin besar faktor Rician dan makin banyak kode, delay kanal semakin kecil. Rasio capture makin besar, delay kanal semakin besar. Dengan diikutsertakan efek capture, throughput kanal slotted ALOHA CDMA lebih tinggi dan delay lebih rendah dibandingkan dengan tidak diikutsertakan efek capture.

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In mobile communication, fading can lower performances of the system. We can improve the performances by using capture effect. Capture effect is a condition that a packet can capture the receiver even though the packet arriving at the receiver overlaps in time with other packet. This paper presents an analysis of performances of access method slotted ALOHA-CDMA in LEO satellite system which include the influence of both fading in Rider'? and capture effect. The performances of system are characterized by probability of packet success, channel throughput and delay.

It is shown from the results that whenever traffic non uniformity decreases, the probability of packet success and throughput increase and delay slotted ALOHACDMA decreases. The increasing of Rician parameter and number of code in the network cause the increasing in probability of packet success and throughput and the decreases in delay. If capture ratio decreases, probability of packet success and throughput of slotted ALOHA-CDMA increases. Whenever capture ratio increases slotted ALOHA-CDMA channel delay increases."

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Teknologi komunikasi nirkabel dari Internet of Things (IoT) saat ini sudah digunakan dalam banyak kasus. Pada tahun 2016 (3rd Generation Partnership Project) 3GPP memperkenalkan teknologi baru yang disebut Narrowband Internet of Things (NB-IoT). Dengan target melayani pasar perangkat IoT, NB-IoT dirancang untuk menjadi lebih baik dalam menangani sejumlah besar perangkat, dibandingkan dengan teknologi seluler yang ada. Tantangan terbesar untuk melayani sejumlah besar perangkat dalam teknologi nirkabel adalah random access. Penelitian ini menyajikan hasil simulasi prosedur random access pada kestabilan NB-IoT dengan sejumlah besar perangkat. backoff window adalah fokus utama dalam penelitian ini untuk mengevaluasi kinerja NB-IoT yang memiliki kemampuan untuk meminimalkan paket Loss sehingga dapat mengirim lebih banyak paket yang di-acknowledge. mekanisme backoff dengan limitasi pengulangan diasumsikan bekerja pada satu tingkat Coverage Enhancement (CE). Hasil penelitian menunjukkan bahwa probabilitas pengiriman paket juga memiliki peran dalam kinerja, di mana semakin tinggi probabilitas untuk mengirimkan paket, semakin tinggi paket Loss terjadi. Jumlah pengguna (M) maksimum untuk PPKT 10% adalah 45 dengan persentase rata-rata Loss sebesar 49,59%, 35 untuk PPKT 20% dengan persentase rata-rata Loss sebesar 49,49%, dan 30 untuk PPKT 30% dengan persentase rata-rata Loss sebesar 47,86%.

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Next generation wireless communication technology of Internet of Things (IoT) nowadays is already used in many use cases. In 2016 3GPP (3rd Generation Partnership Project) started introducing a new technology called Narrowband Internet of Things (NB-IoT). Targeting to serve the market of IoT devices, NB-IoT is designed to be better in dealing with massive number of devices in a cell, compared to the existing cellular technologies. The biggest challenge to serve massive number of devices in wireless technologies is the random access. This research presents a simulation result of NB-IoT’s random access procedure under massive number of devices in steady-state condition. A backoff window is the main focus in this research to evaluate the NB-IoT performance, it has the ability to minimize packet loss so it can send more an acknowledged packet. the backoff mechanism with retry limit is considered with one coverage enhancement (CE) level. The result shows that a probability of transmitting packet also has a role in performance, where the higher of probability to generate uplink packet, the higher the lost packet will occur. The maximum number of users (M) for PPKT 10% is 45 with an average percentage of loss rate is 49.59%, 35 for PPKT 20% with an average percentage of loss rate is 49.49%, and 30 for PPKT 30% with an average percentage of loss rate is 47.86%.

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"This book provides a comprehensive treatment of the theoretical foundation and algorithmic tools necessary in the design of efficient tag counting and monitoring algorithms in emerging RFID systems. The book delivers an in-depth analysis on the following problems ranging from theoretical modeling and analysis, to practical algorithm design and optimization: Stability analysis of the frame slotted Aloha protocol, the de facto standard in RFID tag counting and identification; Tag population estimation in dynamic RFID systems; Missing tag event detection in the presence of unexpected tags; Missing tag event detection in multi-group multi-region RFID systems. The target readers are researchers and advanced-level engineering students interested in acquiring in-depth knowledge on the topic and on RFID systems and their applications."