Experimental analysis of wireless data-transmission systems in space platforms

This paper presents an experimental analysis of the use of wireless data-transmission systems in manned space platforms. Previous studies have analyzed the general advantages of substituting radio systems for some of the harnesses in the platforms. This paper presents a detailed experimental characterization of the radio channel in the environment of a space platform at frequency bands of 2.5 GHz and 17 GHz. For this purpose, a mockup, based on the Columbus Space Laboratory, was built. The probability distribution functions of the fading have been obtained for narrow-band as well as wideband parameters, such as the mean square delay and the coherence bandwidth of the channel. Moreover, a study of the operating mode of a commercial wireless system, based on the IEEE 802.11 b standard, has been performed, by monitoring the bit-error rate. The error rates of the IEEE 802.11 b system in the typical environment of a small or medium-sized office are compared with those of a space-platform environment. The results and conclusions can be extended to other environments that present geometrical and structural characteristics similar to those of a space platform, such as ships and submarines.