Urban wideband measurements at 1.8 GHz with different chirp bandwidths

Wideband measurements of mobile radio provide both small-scale and large-scale characterisation of the multipath fading envelope of the received signal and time delay channel descriptors. In this paper, a wideband chirp sounder, with different sweep rates is used to provide time domain channel characterisation of the urban city of Dublin. The average power delay profile (APDP) is determined from the collected data for three chirp bandwidths; 10, 36 and 72 MHz. Small-scale characterisation is achieved by consecutive impulse response measurements over a few wavelengths. By repeating the measurements at different geographical locations, large-scale channel characterisation can be obtained. From the APDPs, the fading envelope and time domain channel descriptors such as the average delay, delay spread, time delay widths are extracted. The results are presented in the form of cumulative distribution functions, which are compared with empirical distributions. These various channel descriptors provide valuable information to assess the behaviour and the performance of digital mobile communication systems for intersymbol interference in multipath, frequency selective fading media