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5th generation mobile communication system using higher frequency band has gotten much attention, and massive-MIMO technologies have been expected to improve spectral efficiency dramatically. In order to reduce the complexity of massive-MIMO base station, the combination of analog beamforming (APAA: Active Phased Array Antenna) and digital MIMO signal processing for the multi-beam multiplexing is one of the promising approaches. In this paper, channel capacity evaluation with 44GHz-band APAA measurement results will be carried out and the possibility of large capacity transmission in LOS environment is shown. 44GHz band channel parameters -AoA, AoD, delay spread, etc. -will be shown and transmit performance results using cluster model are presented.

Heterogeneous wireless systems such as a combination of mobile broadband wireless access (MBWA) and wireless local area network (WLAN) are candidates to attain the large capacity in the next generation mobile communication systems. For capacity expansion, small cells of multiple wireless network are deployed densely in these systems. Because a number of the cells overlap, users must discover a lot of cells at once for cell selection. As a result, radio resources are much used for cell discovery in dense small cell environment. We have proposed the efficient network selection scheme using the positioning information and the map information. Using the map information, users can select the cell which has a better channel quality without cell discovery. In this paper, for further enhancement of system performance, new selection scheme considering the traffic load is evaluated. Using this load information, user select a network based on the expected throughput and their location. Consequently, users can avoid the congested network and select one which has a low traffic demand. We discuss the user throughput of the proposed scheme by comparing with the conventional one where users select by measured instantaneous signal strength. The simulation results show that the proposed scheme can improve the average user throughput by 52.8 % in comparison with the conventional one. These performances can be achieved by feasible positioning accuracy.