Multiple-input multiple-output (MIMO) radio channel measurements

Summary form only given. Multiple antennas at both the transmitter and receiver have the potential to significantly increase the capacity of a wireless communications channel. That is, using multiple-input (MIMO) techniques with these antennas, multiple independent channels can be supported in the same bandwidth, but only if the scattering environment is rich enough. Recent research has shown that high theoretical capacity is possible-data rates as high as 40 bits/s/Hz have been demonstrated (in an indoor slow fading environment). However, in cellular mobile radio, the channel differs in several important ways from the indoor channel. Therefore, to determine the potential of MIMO techniques for 3G and 4G wireless systems, we conducted the first field tests to characterize the mobile MIMO radio channel in a typical cellular environment. We present field test results showing the potential increase in capacity using 4 transmit and 4 receive antennas at both the base station and terminal in a mobile environment.