An experimental evaluation of the subscriber antenna pattern effect in a MIMO-OFDM system

The antenna pattern impact on a 2/spl times/2 MIMO-OFDM broadband system is studied by evaluating radiation efficiency, received power, antenna pattern correlation, and the spatial characteristics of various antennas and pairs of antennas. Four different multiple antenna portable devices are described and analyzed. Three of the devices were developed with current Motorola cell-phone plastics where the antennas were mounted. The fourth device was developed on a laptop. Antennas and pairs of antennas for the different devices are compared, first apart from the environment through analysis of anechoic chamber measurements of the antenna patterns, and then in indoor environments through field measurements. Spatial characteristics in an outdoor environment are predicted by incorporating the measured portable antenna patterns into the suburban propagation environment estimated in previous data collection efforts with vehicle rooftop antennas.