Performance Evaluation of Practical Passive Source Localization Using Two Software Defined Radios

Passive source localization has been a hot topic for many years. It is traditionally implemented using multiple spatially distributed stationary sensors. In this letter, a passive localization solution using two sensors is proposed. To demonstrate the solution in the real-world environment, a localization system is developed using commercial-off-the-shelf software defined radios. One stationary sensor and one mobile sensor are developed to take time difference of arrival and frequency difference of arrival measurements at multiple time instants to localize a non-cooperative signal tower. To improve the localization accuracy, the measurement error is systematically analyzed. Moreover, the methods to select appropriate measurements are discussed. The localization performance of the system is evaluated via the experiments implemented in a large outdoor area with a sensor-target range of several kilometers.