Interference Effects of Multi-User Ultrawideband (UWB) Communication Systems
Ultrawideband (UWB) communication systems are based on the transmission and reception of extremely short duration (picosecond or nanosecond) bursts of radio-frequency energy. The resulting waveforms have extremely wide bandwidth, on the order of multiple gigahertz. Because the signal energy is spread over such a wide bandwidth, UWB signals may contribute relatively little interference to other systems that share portions of the UWB communications band. Multiple UWB signals can share a frequency band through a technique known as time-hopping.
The project involved modeling a number of UWB transmitters to calculate the interference noise level at a victim receiver, picked to be a certain distance away. The model for the transmitters turning on and off was based on a Markov chain, and the UWB signals were viewed as Gaussian noise; initially the analysis was done where all the transmitters were at a constant distance away from the receiver. An event-driven Monte Carlo simulation was then developed on MATLAB to represent a random-distance distribution of multiple transmitters. This led to the conclusion that many transmitters may cause major problems in worst cases, thus it is very important to thoroughly examine those cases.