Uplink-Oriented Deployment Guidelines and Auto-Configuration Algorithms for Co-Channel W-CDMA Heterogeneous Networks

The operation of wireless cellular networks can be efficiently supported by secondary small cells that are deployed at traffic hotspots within the coverage area of the primary macro cells. To this end, we examine the conditions under which the secondary base stations can share the same communication channel with the primary base stations under the constraint of a predefined quality of service, typical for uplink communications. In particular, requiring a target signal-to-interference-and-noise ratio (SINR) for each transmission accommodated in a common interference-limited channel, we formally assess the impact of the secondary infrastructure in a W-CDMA system on the global achievability of the uplink target SINRs via distributed closed-loop power control. The effects of cell load and inter-cell coupling are distinguished. As a result, we define solutions to the problems of base station placement, cell coverage optimization, and target SINR adaptation in W-CDMA heterogeneous networks, as well as discuss their compatibility with standard downlink-oriented deployment guidelines. Analytical conclusions are validated numerically by 3GPP-compliant simulations of a W-CDMA heterogeneous network.