Maximizing WCDMA network packet traffic performance: multi-parameter optimization by gradient descent minimization of a cost function

WCDMA networks have many parameters which determine their performance. Ensuring a desired quality of service means a proper choice of network and cell parameters. One approach to choosing these parameters automatically is to minimise a cost function with respect to these parameters. The minimum of the cost function corresponds to an optimal network performance. The choice of cost function, in the simplest ease can be some combination of key performance indicators (KPTs) of the network. Here a cost function is described which can be used to simultaneously optimize 5 network parameters, to maximize the uplink and downlink packet data traffic. A stochastic, second order gradient method is described that can be used to simultaneously perform the optimization of the cost function. The cost function and gradient algorithm are implemented on an advanced WCDMA radio network simulator. Significant increases, in the packet throughput in a dynamically optimized scenario are found, relative to the same scenario with a typical but constant parameter set.