Analisa Unjuk Kerja Sistem Downlink Dedicated Channel (DCH) Pada Wideband CDMA

Sistem seluler Wideband Code Division Multiple Acces (WCDMA) saat ini berkembang sangat pesat pada tugas akhir ini dilakukan Analisa Unjuk Kerja Sistim Downlink Dedicated Channel (DCH) pada Wideband CDMA. Untuk menganalisa performa atau unjuk kerja dari sistem Downlink DCH pada Wideband CDMA dicari nilai kesalahan bit pada saat pengiriman yang biasa dikenal dengan nama Bit Error Rate pada Cyclic Redundancy Check (CRC) dan channel coding dengan input Dedicated Traffik Channel (DTCH) dan Dedicated Control Channel (DCCH) dicari nilai Bit Error Rate (BER) pada sistem Downlink Dedicated Channel (DCH) Wideband CDMA dan dicari nilai Block Error Rate (BLER) pada sistem Downlink Dedicated Channel (DCH) Wideband CDMA. Analisa ini menggunakan piranti lunak Matlab 7.0.1 untuk mengetahui jumlah kesalahan Bit Error Rate (BER) dengan jenis kanal Multipath Fading. Dari hasil simulasi dengan Input 106 pada 7 dB dengan menggunakan Eb/No dari 1 hingga 7 dB maka didap atkan Bit Error Rate dengan nilai Bit Error Rate BER 1,8 x 10^-6.

Mobile Commerce Technology

With the introduction of the World Wide Web, electronic commerce has revolutionized traditional commerce and boosted sales and exchanges of merchandise and information. Recently, the emergence of wireless and mobile networks has made possible the admission of electronic commerce to a new application and research subject—mobile commerce, which is defined as the exchange or buying and selling of commodities, services, or information on the Internet through the use of mobile handheld devices. With services provided by mobile commerce, consumers may use the microbrowsers on their cellular phones or PDAs to buy tickets, order meals, locate and book local hotel rooms, even write contracts on the move. In just a few years, mobile commerce has emerged from nowhere to become the hottest new trend in business transactions. NTT DoCoMo’s i-mode (2003) is by far the most successful example of mobile commerce. Introduced in February 1999, i-mode has attracted over 36 million subscribers worldwide. With i-mode, cellular phone users can easily access more than 62,000 Internet sites, as well as specialized services such as e-mail, online shopping and banking, ticket reservations, and personalized ringing melodies that can be downloaded for their phones. The i-mode network structure not only provides access to i-mode and i-mode-compatible contents through the Internet, but also provides access through a dedicated leased-line circuit for added security. i-mode users are charged based on the volume of data transmitted, rather than the amount of time spent connected. In Spring 2001, NTT DoCoMo introduced its next-generation mobile system, based on wideband CDMA (W-CDMA), which can support speeds of 384Kbps or faster, allowing users to download videos and other bandwidth-intensive content with its high-speed packet data communications.