Performance evaluation of UWB signal transmission over optical fiber

UWB over fiber (UWBoF) technique has been proposed to increase the area of coverage for UWB communication systems. In this paper, the transmission performance of impulse UWB signals over optical fiber is analyzed. Three types of UWB signals generated based on three different techniques are considered. Since optical signals with different optical spectra would have different tolerances to fiber dispersion, the transmission performance of the three types of UWB signals is studied. First, the impact of fiber chromatic dispersion on UWB waveforms and their spectra is evaluated. Then, the transmission performance of data-modulated UWB signals in an optical fiber is investigated, with a general model to analyze the signal power spectral density (PSD) being developed. The PSD of an UWB signal with on-off keying (OOK), bi-phase modulation (BPM) and pulse position modulation (PPM) schemes is calculated. Evolution of the PSD as a function of transmission distance is then performed. The suitability of the three types of UWB signals for UWBoF applications is also evaluated. The study provides a guideline for the design and development of a practical UWBoF system.