Detail Intelligent Antenna System for cdma2000   Oleh:  Soni, R. A. ; Buehrer, R. M. ; Benning, R. D. Jenis: Article from Bulletin/Magazine Dalam koleksi: IEEE Signal Processing Magazine vol. 19 no. 4 (2002), page 54-67. Topik: antenna; intelligent; antenna system; CDMA 2000 Ketersediaan Perpustakaan Pusat (Semanggi) Nomor Panggil: SS26.6 Non-tandon: 1 (dapat dipinjam: 0) Tandon: tidak ada     Lihat Detail Induk Isi artikel Third - generation (3G) cellular code division multiple access (CDMA,) systems can provide an increase in capacity for system operators over existing second - generation (CDMA) systems. The gain in capacity for the base station to mobile (forward) link can be attributed to improvements in coding techniques, fast power control, and transmit diversity techniques. Additional gains in the mobile to base station (reverse) link can be attributed to the use of coherent quadrature phase shift keyed (QPSK) modulation and better coding techniques. While these enhancements can improve the performance of the system, system operators expect that with increased demand for data services, even greater capacity enhancements may be desired. There are essentially three methods, which we describe, based on diversity, spatial beamforming, and a combination of diversity and beamforming, to improve the performance of system through the use of additional antennas at the base station transmitter and receiver. The performance improvements are a function of the antenna spacings and the algorithms used to weight the antenna signals. We focus on the possibilities for the cdma2000 3G system that do not require standards changes. We highlight the performance enhancements that can be obtained on both the reverse and forward links through use of an antenna array architecture that supports a combination of beamforming and transmit diversity. We focus on the performance enhancements for the forward link. Opini Anda Klik untuk menuliskan opini Anda tentang koleksi ini! Kembali

Copyright © 2006, 2007 Unika Atma Jaya, all rights reserved