Showing papers by "Geoffrey G. Messier published in 2001"

An indoor IS-2000 transmit diversity evaluation using propagation measurements

Abstract: Several transmit diversity schemes have been proposed to improve the forward link performance of next generation IS-2000 CDMA systems. These techniques are expected to perform particularly well in indoor environments. A simulation that processes propagation measurements is used to illustrate how indoor transmit diversity performance varies with base station configuration. Dynamic impulse response measurements are collected using IS-95 base station pilot signals. These measurements characterize the forward channel in an indoor office environment for three base station configurations. The propagation data is processed in a simulation to evaluate the performance of space time spreading, time delay transmit diversity, phase sweep transmit diversity and orthogonal transmit diversity for the different base station configurations.

CDMA forward link performance evaluation using propagation measurements

Abstract: Many IS-95 CDMA networks currently deployed in the field are forward link capacity limited. The introduction of IS-2000 is intended to improve forward link performance and increase system capacity. However, the performance improvement provided by IS-2000 will vary with propagation environment. A technique for collecting forward channel impulse response measurements using IS-95 pilot signals is presented. This technique is used to characterize the forward channel in residential and urban regions in Calgary, Canada. The propagation data is then processed in a simulation in order to generate a comparison of IS-95 and IS-2000 performance that is specific to these environments. The results illustrate how the propagation environment can affect the performance improvement provided by IS-2000.