The wide-band nature of ultra-wide band impulse radio (UWB-IR) systems, recently proposed as the winner candidate for IEEE 802.15.3a standard, presents as a drawback the poor coverage, mainly in faded scenario where, according to FCC Part 15 rules for power spectral mask emission, the power is extremely limited. So, in order to achieve a target BER typical of multimedia applications, it is impossible to assure high performance without requiring the user terminals very close to UWB stations. The only way to solve this limitations is a diversity approach, and, since the employment of multiple-antenna systems does not seem to be expensive, in this contribution multiple-antenna UWB-IR systems are taken into account, by proposing coding schemes and corresponding detectors, (in the general case of partial channel knowledge) in order to improve performance in terms of coverage and BER