Adaptive algorithms for improving the throughput in an indoor mobile s-aloha ds-cdma system

This paper presents a novel Adaptive DSCDMA Slotted-ALOHA packet random access scheme with transmitter-based spreading codes for mobiles. It is aimed at improving the throughput and message delay delivery when traffic load values below the saturation point of the conventional DS-CDMA Slotted-ALOHA system are sensed in the channel. For this purpose, one Mobile and two Base Station assisted algorithms are envisaged to control the change of the transmission rate according to the traffic load. These algorithms revealed that the optimum behavior, obtained using a Markov Chain model, may be almost reached at a low complexity cost.Peer ReviewedPostprint (published version

An investigation into advance time division multiple access based personal communication networks : this thesis is presented in partial fulfilment of the requirements for the degree of Master of Technology in Production Technology at Massey University

This thesis examines and simulates a statistically multiplexed multiple access technique known as Advanced Time Division Multiple Access (ATDMA). The simulations were carried out in a multimedia traffic environment. Parameters that could optimise the network performance in terms of quality, reliability and capacity have been examined using a simulation model. This thesis also examines network architecture and signalling related issues. The simulation results were analysed to propose a suitable ATDMA frame structure in terms of the frame length and the organisation of traffic and reservation slots. The simulation results indicated that the performance of the ATDMA based system can be enhanced when delay insensitive data is transmitted as blocks of packets of a specific size. The simulation results also indicated that the performance of the ATDMA based system can be further enhanced when a video terminal is allocated a single traffic slot as opposed to multiple traffic slots. Further simulations have been carried out to determine the up-link traffic channel capacities and control channel capacities. This thesis also examined aspects that could further enhance the performance of an ATDMA based system

STUDI INTEGRASI JARINGAN MULTIMEDIA B-ISDN/ATM DENGAN UMTS (Universal Mobile Telecommunication System)

Perkembangan implementasi dari komunikasi multimedia mengarah pada struktur jaringan kabel yang sudah ada, namun tidak memungkinkan untuk dapat dipakai di sembarang tempat karena ketiadaan perangkat yang portable. UMTS sebagai sistem telekomunikasi generasi ketiga dipersiapkan untuk dapat mendukung komunikasi data dan multimedia serta dapat mendukung bermacam-macam layanan yang ditawarkan oleh jaringan tetap yang ada saat ini termasuk dengan jaringan B-ISDN. UMTS mempertimbangkan layanan laju data radio sebesar 144 Kbps sampai 2 Mbps untuk mendukung berbagai macam layanan data multimedia dimana jenis dari akses radio tersebut akan menjangkau dari sambungan dengan laju bit yang konstan maupun yang variabel, akses paket yang berorientasi koneksi sampai akses paket yang tak terkoneksi pada band frekuensi 2 GHz. Integrasi yang dilakukan menggunakan fasilitas infrastruktur jaringan yang sudah ada yang berbasiskan pada ATM transport dan integrasi dengan konsep IN serta mendukung pemakaian antarmuka radio serta mengadopsi IP (Internet Protocol) switching dan aplikasi protokol yang dapat digunakan untuk interaksi antara entitas yang menyilang dari antarmuka yang digunakan untuk aplikasi protokol manajemen UMTS adalah bebas, antara lain SNMP, CNIP dan CORBA. Dengan mobilitas, laju bit dan band frekuensi yang besar serta fleksibilitas yang dipunyai UMTS maka proses integrasi dengan jaringan multimedia B-ISDN/ATM dapat dimungkinkan dengan kualitas layanan yang identik dengan jaringan yang sudah ada

A resource management architecture for future mobile communications systems

This paper presents an overview of a hierarchical Resource Management architecture for future mobile communications systems. The architecture is designed to be generic and can therefore be adopted for a range of Radio Access Methodologies. In particular it provides a mechanism for radio resource management across airinterfaces such as those being defined for use with UMTS. Given the move towards packet-switched technologies both in the Core Network and the Radio Access Network [1], the architecture embraces the concept of statistical QoS applied to individual flows in the form of a commitment level. I