Empirical Analysis of 2 × 2 Outdoor-Indoor MIMO Channels for FBWA Applications

The use of multiple antennas at both sides of the communication channel strongly improves the performance of the wireless communication system, increasing spectral efficiency and/or channel reliability. These advantages are very suitable for wireless local area networks (WLAN) and wireless metropolitan area networks (WMAN). This paper focuses on the study of fixed wireless broadband access (FWBA) services in metropolitan areas, making two main contributions. First, the experimental characterization of a 2times2 MIMO channel at a frequency of 2.4 GHz in canonical outdoor-indoor scenarios is presented. The channel characterization performed includes the analysis of the spatial correlation between the MIMO system subchannels and its impact on the channel capacity. Second, on the basis of the capacity results obtained, a proposal is made for the use of a 2times2 MIMO system in outdoor-indoor scenarios for FBWA applications in metropolitan environments. The proposal is based on the hypothesis, verified experimentally, that the path loss due to building penetration can be practically compensated by the diversity gain of 2times2 systems