A Clustering Approach for Multiband Neighbor Discovery on 60 GHz WLAN

Abstract

The 60 GHz mmWave unlicensed band has a very large spectrum available, divided into four orthogonal channels, which allows up to 7 Gbps data rate. On the other side, the propagation in the 60 GHz band is subject to severe path loss attenuation, which can be mitigated using highly directional antennas. This high directionality brings a new challenge to neighbor discovery; the devices now need to know the exact neighbors’ physical location to successfully communicate with them. In order to expedite the neighbor discovery process, multiband protocols have been proposed in the literature in which a separate band is used for the exchange of control messages in an omnidirectional mode. Nonetheless, these proposals suffer from the control channel bottleneck problem due to the numerous messages that need to be exchanged in this channel. In this work, we propose a scheme that divides the network nodes in clusters and for each cluster we allocate one separate control channel and also a separate mmWave channel for beamforming only. The former separation allows decreasing the number of control messages exchanged in each control channel, and the latter allows the simultaneously execution of multiple beamforming. In conjunction to this clustering scheme, we propose a multiband protocol in which only the cluster leader performs beamforming and uses the control channel to propagate the information obtained during this process. We compare the existing protocols with our proposed clustering protocol in terms of average transmission time, overhead, and accuracy of neighbor discovery information.

Wi-Fi Assisted Contextual Multi-Armed Bandit for Neighbor Discovery and Selection in Millimeter Wave Device to Device Communications

“…Although the authors made a successful practical experimental setup, their algorithm still does direct NDS with nearby devices and does not choose the best nearby device as in our case. In [ 30 ], the authors proposed a clustering scheme that splits the network nodes into clusters. Each cluster assigns one separate control channel and a particular mmWave channel for beamforming only.…”

“…In [ 31 ], the authors suggested exploiting the context info associated with user position, handled by a separate control channel to advance the cell discovery process with minimizing its time delay. The schemes in [ 30 ] and [ 31 ] need an extra control channel, which increases the ND overhead, unlike our proposal that does not require any extra control channel. Employing linear programming, the authors of [ 32 ] proposed a distributed random mmWave-based discovery algorithm, where each device finds the relevant algorithm parameters, i.e., transmission and beam steering probabilities, using the information provided from the microwave band.…”