If the network in the Shinjuku station area of Tokyo can cope with the highest density of subscribers imaginable, then you have nothing to worry about. The problem isn’t network capacity. In preparing for heterogeneous networks, operators should start by improving the macro layer. By doing this, they can create enough network capacity to handle even the most extreme case of smartphone-traffic onslaught and avoid the pitfall of premature over-investment in smaller nodes.Approximately 3.5 million subscribers every business day are on the move in the square kilometer surrounding Tokyo’s Shinjuku station. The challenge for the operator was to build a network with world-class smartphone capacity in an area with the highest concentration of smartphone users in the world.Network performance should be improved by carefully following the stepwise process of building a heterogeneous network. First, macro-network performance is enhanced. Second, all available spectrum is used. Only at this point, if additional network capacity and improved coverage are still required, should densification of macro sites be considered. The last step of the process involves adding low-power nodes. If the process is not followed in the right order then the end result is likely to be a network that is sub-optimized.
