environment. © 2009 by Taylor & Francis Group, LLC Long Term Evolution: 3GPP LTE Radio and Cellular Technology Repeatability of Continuous Sequences 50.00 45.00 40.00 35.00 30.00 25.00 20.00 15.00 CH2 cont 10.00 CH6 cont CH13 cont # of Measurements Figure 12.13 Nine consecutive measurements showing good repeatability. Having shown that it is possible to do measurements with good repeatability, the next step was to compare a MIMO 802.11n configuration with a standard SISO 802.11g configuration. The throughput in the 802.11n MIMO 3 X 2 con- figurations was compared with the 802.11g mode of the router. For both operation modes, the modulation format was set to the most complex implemented-for 802.11n MCS 15 with 20-MHz bandwidth, 130 Mb/s rate medium access control (MAC) data, and for 802.11g, 54 Mb/s physical link rate. Three measurements were taken and averaged for each of the frequency channels. The results are shown in Figure 12.14 and show how 802.11n with MIMO dra- matically improves the throughput compared to 802.11g, which uses only SISO. This means an absolute increase of at least 25 Mb/s and represents on average nearly three times the throughput offered in the older standard. It was also possible to Comparison of WLAN Standards 802.11 n 802.11 g Channel # Figure 12.14 Comparison of WLAN standards. © 2009 by Taylor & Francis Group, LLC Measuring Performance of 3GPP LTE Terminals see effects of removing or attenuating one or two antennas at the router. For more information about this, as well as how different types of antennas affected the throughput, see Olano et al. [57]. A new setup for active measurements of throughput of MIMO systems in the reverberation chamber has been described. The chosen communication standard was WLAN 802.11n, which was the first communication standard to commer- cialize devices implementing MIMO. WLAN has traditionally been a computer networking standard and, compared to cell phone standards, presents some special features regarding its operation and characterization. However, w