Statistical characteristics of an ensemble of ultrawideband communications channels under the conditions of multipath signal propagation in rooms

Abstract

The estimates of data rates in the ultrawideband direct chaotic scheme of data transmission in rooms, which can be achieved at a specified level of error probability under the conditions of multipath signal propagation in wireless communications networks, are presented. The estimates have been obtained via direct numerical simulation of energy reception of chaotic signals at the output of communications channels. The channel impulse responses were formed according to the statistical model developed by the IEEE 802.15 working group for indoor applications. In the approximation of a dominant reverberation interference (multipath propagation), the portion of channels making it possible to transmit data with rates from 10 to 50 Mb/s and the practically important error probability (Pb ∼ 10−5−10−4) is determined for the chaotic signal bandwidths Δf = 500 and 2000 MHz. It have been first revealed that, in the given ensemble of channels, the small portion of channels (5–20%) with high levels of error probability Pb substantially affects the dependence of the error probability averaged over the given type of channels (\( \bar P_b \) (R)) on the transmission rate. It has been demonstrated that quantity \( \bar P_b \) (R) is the practically important characteristic of noise immunity for the significant portion (∼80–95%) of channels of the given type.