The location of a mobile unit in the service area of a CDMA wireless communications system is determined by a location probability distribution procedure that is based entirely on analytical results derived from an integrated model of the wireless communications system, its RF environment and attribute measurement. The mobile unit measures and reports attribute values of pilot signal strength of all pilot signals visible to the mobile unit at its present location, whereupon a location probability distribution is computed based on a Bayesian probability algorithm including a set of stored model parameters.