Monitoring using GNSS technology has played a very important role in tracking all manner of items, ranging from dangerous firearms to cash, and to the tracking of stolen vehicles. In different environments there will be times when the surroundings pose problems to the GNSS receiver, such as in the case where shipping containers are being stacked on top of each other, thus limiting the view of t...

This paper discusses an ultra-wideband (UW) tracking system design effort for Mini-AERCam (Autonomous Extra-vehicular Robotic Camera), a free-flying video camera system under development at NASA Johnson Space Center for aid in surveillance around the International Space Station (ISS). UWB technology is exploited to implement the tracking system due to its properties, such as high data rate, fin...

Abstract To achieve more accurate measurements of the MS location, it is possible to integrate many kinds of schemes. In this paper we combine time difference of arrival (TDOA) from three base stations (BSs) and angle of arrival (AOA) information at the serving BS to give location estimation of the MS. Based on the non-line-of-sight (NLOS) environments and the knowledge of NLOS error statistics...

This paper provides analysis of identification of acoustic transfer functions between two microphones and investigation of modified application from two-microphone adaptive noise cancelling and beamforming methods. Based on this, we will perform real-time performance comparisons to obtain the best solution to speech enhancement and noise cancellation. Experiments are processed by software imple...

Determining the spatial position of a speaker finds a growing interest in video conference scenario where automated camera steering and tracking are required. As a preliminary step for the localization, microphone array can be used to extract the time difference of arrival (TDOA) of the speech signal. The direction of arrival of the speech signal is then determined by the relative time delay be...

This paper proposes an initialization for an agglomerative system applied to speaker diarization in the meeting environment. The initialization is based on a previous clustering of the temporal sequence generated by the estimation of the Time Delay of Arrival (TDOA) among pair of sensors. That initial clustering has the purpose of obtaining initial classes with speaker information from a sole s...

Time delay of arrival (TDOA) estimation between signals input to two or more microphones plays an important role in speaker localization. Most methods employ a linear array of two or more microphones and use the generalized cross correlation method or eigenspace analysis (AEDA) methods. TDOA estimation with linear arrays, however, is highly sensitive to estimation errors when the signals arrive...

Speaker diarization for recordings made in meetings consists of identifying the number of participants in each meeting and creating a list of speech time intervals for each participant. In recently published work [7] we presented some experiments using only TDOA values (Time Delay Of Arrival for different channels) applied to this task. We demonstrated that information in those values can be us...

We present a new distortion measure for compression in systems that share data in order to locate RF signal emitters and discuss its optimal use. These results are relevant in wireless location systems, electronic warfare systems, and sensor networks. The optimal bit allocation with respect to this distortion measure is accomplished through use of a genetic algorithm with a penalty function. We...

This paper addresses the source location problem by using time-difference-of-arrival (TDOA) measurements. The two-stage weighted least squares (TWLS) algorithm has been widely used in TDOA location. However, estimation accuracy of is poor and bias significant when measurement noise large. Owing to nonlinear nature system model, we reformulate localization as a constrained derive theoretical est...