This paper provides a stochastic geometry framework to perform the coverageand rate analysis of a typical user in co-existing VLC and RF networks coveringa large indoor area. The developed framework can be customized to capture theperformance of a typical user in various network configurations such as (i)RF-only, in which only small base-stations (SBSs) are available to provide thecoverage to a user, (ii) VLC-only, in which only optical BSs (OBSs) areavailable to provide the coverage to a user, (iii) opportunistic RF/VLC, wherea user selects the network with maximum received signal power, and (iv) hybridRF/VLC, where a user can simultaneously utilize the available resources fromboth RF and VLC networks. The developed model for VLC network preciselycaptures the impact of the field-of-view (FOV) of the photo-detector (PD)receiver on the number of interferers, distribution of the aggregateinterference, association probability, and the coverage of a typical user.Closed-form approximations are presented for special cases of practicalinterest and for asymptotic scenarios such as when the intensity of SBSsbecomes very low. The derived expressions enable us to obtain closed-formsolutions for various network design parameters (such as intensity of OBSs andSBSs, transmit power, and/or FOV) such that the number of active users can bedistributed optimally among RF and VLC networks. Also, we optimize the networkparameters in order to prioritize the association of users to VLC network.Finally, simulations are carried out to verify the derived analyticalsolutions. Important trade-offs between height and intensity of OBSs arehighlighted to optimize the performance of a user in VLC networks.
展开▼
