Accession Number:

ADA415205

Title:

Uniform Circular Antenna Array Applications in Coded DS-CDMA Mobile Communication Systems

Descriptive Note:

Master's thesis

Corporate Author:

NAVAL POSTGRADUATE SCHOOL MONTEREY CA

Personal Author(s):

Report Date:

2003-03-01

Pagination or Media Count:

77.0

Abstract:

Presently, the uniform linear array ULA is the most commonly used antenna system for a sectorized cell system like commercial cellular systems. However, in many omni-directional cell communication systems, such as ground-based military communications, interest in using the uniform circular array UCA has greatly increased. This thesis examines the use of an equally spaced circular adaptive antenna array at the mobile station for a typical coded direct sequence code division multiple access DS-CDMA communication system. The author analyzed the performance of a randomly orientated adaptive UCA in the forward channel base station to mobile station of a coded multi-cell DS-CDMA system. Using a 3- and 4-element UCA, the capacity and performance of different cellular systems under a range of shadowing conditions, with and without antenna sectoring at the base station and for various user capacities, were simulated using the Monte Carlo method. The results for both ULA and UCA are compared and presented in this thesis. The simulation results show that, generally, the performance of the system with the adaptive UCA is better than, or at least on par with, the system with the adaptive ULA. In addition, the 4-element adaptive array can null out up to three interfering signals, thereby increasing the systems capacity. Furthermore, sectoring techniques significantly reduced the amount of inter-cell interference and improved the systems performance, thereby increasing the number of mobile stations allowed within the cell. The capacity of the system with the 3- and 4- element adaptive UCA was increased by 5.8 times with 60 degree sectoring and 2.8 times with 120 degree sectoring, respectively. 37 figures, 9 refs.

Subject Categories:

  • Electrical and Electronic Equipment
  • Radiofrequency Wave Propagation
  • Radio Communications

Distribution Statement:

APPROVED FOR PUBLIC RELEASE