Spatial Domain Resource Sharing for Overlapping Cells in Indoor Environment

Abstract

As microcell wireless systems become more widespread, intercell interference among the access points will increase due to the limited frequency resource. In the overlapping cell scenario, radio resources should be shared by multiple cells. Although time and frequency resource sharing has been described in many papers, there is no detailed report on dynamic spatial resource sharing among multiple cells for microcell wireless systems. Thus, we present the effectiveness of spatial resource sharing among two access points. We introduce two scenarios based on the zero forcing method; one is the primary-secondary AP scenario and the other is the cooperative AP scenario. To evaluate the transmission performance of spatial resource sharing, channel matrices are measured in an indoor environment. The simulation results using the measured channel matrices show the potential of spatial resource sharing.

Evaluation of inter-cell interference suppression using tunable beam-width microstrip antenna in actual indoor environment

“…x represents Hermitian transpose, and 2 ı is noise power [1]. Also, that in Cell #2 can be calculated in the same manner.…”

“…Inter-cell interference suppression methods, such as, transmitting beamforming method [1] and transmitting power control [2], have been invesgated. Transmitting beamforming improves signal to interference ratio (SIR) by suppressing eigenvalue of interference channel.…”

Experimental Results of Network-Assisted Interference Suppression Scheme Using Adaptive Beam-Tilt Switching

“…To suppress ICI between small cells, network-assisted transmit power control (TPC) technologies, which cooperatively suppress ICI by adjusting each transmit power at multiple APs and improve system throughput, have been investigated [11,12]; unfortunately, they also degrade the received power at each station (STA) because of TPC. More recently, network-assisted beamforming technologies also have been investigated [13][14][15][16]. They cooperatively suppress ICI without significantly degrading the received power at each STA except for cases in which the correlation of propagation channels between AP and desired/nondesired STAs is high.…”

Constrained beam selection scheme for WLAN systems

“…Due to the SINR improvement possible in dense AP deployment, dynamic beamforming technologies have been investigated [4,5]. These technologies cooperatively mitigate the inter-cell interference (ICI) power without significantly degrading the RSSI at desired STAs unless the spatial correlation of propagation channels between AP and desired/non-desired STAs is high.…”