Capacity Optimization of IR Ultra-wide Band System Under the Coexistence with IEEE 802.11n
Zhuo Li and Qilian Liang
Considering the potential interference of ultra-wide band (UWB) system to OFDM based narrowband wireless communication system, such as IEEE 802.11n system, this paper investigates the optimal power allocation scheme for Impulse Radio UWB (IR-UWB) user in order to maximize the total transmission rate of UWB within the coexisting frequency range shared with IEEE 802.11n, with the constraints that its interference to IEEE 802.11n user is below a certain acceptable threshold. Therefore, UWB user could reach its best performance regarding to transmission rate, while the coexisting IEEE 802.11n user tends to work normally with permissible interference from UWB user. Simulation results show that the optimal power allocation scheme significantly increases the capacity of UWB user compared with equal power allocation scheme.
Keywords: Ultra-wide band (UWB), IEEE 802.11n, capacity optimization, water-filling, spectrum management, smart grid.