Passive source localization has wide applications in array signal processing. In the practical applications, the observations collected by an array may be “arbitrary”-field signals, i.e., which are either mixed near-field and far-field signals or multiple near-field signals or multiple far-field signals. With a cross array, a two-stage separated steering vector-based algorithm is developed to localize “arbitrary”field narrowband sources in the spherical coordinates. The key points of this paper are: i) different physical steering vectors of near-field Received 1 November 2010, Accepted 23 December 2010, Scheduled 25 January 2011 Corresponding author: Junli Liang (liangjunli@xaut.edu.cn).