The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
Falling is a common health problem for elderly. To address the problem, we are currently developing an acoustic fall detection system, FADE, which automatically detects a fall and reports to the caregiver. Of great importance of the fall detection system is a low false alarm rate that can be achieved by knowing where the acoustic signal comes from. The previous work showed the sound source localization...
The Multiple Signal Classification (MUSIC) algorithm is widely used to estimate the direction of arrival (DOA) of signals impinging on a sensor array. In this work, we analyze the performance of the MUSIC algorithm in the presence of white noise, and when only a random, sample independent subset of the entries in the data matrix are observed, in both the sample rich and deficient regimes. We derive...
A new method of direction finding based on the single channel array is proposed in this paper. By regularly adjusting the beamformer weights of the array, we can calculate corresponding output average power. After making different weighted average on these powers, we can construct a noiseless sparse representation model of the signal power. Then the problem of direction finding is converted into one...
To the problem of making plans, arranging schedules and forecasting for transit agency, the passenger of public traffic is of importance. Compared with the existing application technology, a new passenger statistics solution is introduced. A kind of self-designed contact sensor pedal is used to sample footprint data and identify the direction when passenger gets on and off. The principles of kinesiology...
A method to estimate direction of arrival (DOA) of multi-band signals is proposed in this paper. The authors apply the compressed sensing theory which can reconstruct sparse data in a few measurements, to multi-band signals. Compared to various DOA estimation methods, this approach has produced a considerable improvement of DOA estimation accuracy. Moreover, this proposal can estimate more waves than...
This paper proposes a line-of-sight estimation method using the inter-satellite ranging system based on antenna arrays. GNSS-like technology is inherited such that an existing GNSS receiver is modified to operate as a transceiver and locally generate the inter-satellite ranging signals. Carrier phase measurements are the fundamentals for precise estimation. A robust integer-cycle ambiguity resolution...
This paper describes an approach to designing an ultra-short baseline (USBL) system with a three-dimensional receiving USBL array. In particular, a five-element USBL receiving array based on a five-vertex convex polyhedron (square pyramid) is investigated. The receiving array is oriented as an inverted pyramid and we assume that the receiving USBL array is mounted rigidly on the lower part of the...
We present a hidden Markov model based localization using array sensor. In this method, we use the eigenvector spanning signal subspace as a feature for location. The eigenvector does not depend on received signal strength (RSS) but on direction of arrival (DOA) of incident signals. As a result, the eigenvector is robust to fading and noise. In addition, the eigenvector is unique to the environment...
This paper demonstrates the use of a bed-based optical pressure sensor array to unobtrusively recognize sitting and lying postures as well as lie-to-sit postural transitions. Young healthy, older healthy, older post-stroke, and older post-hip-fracture participants performed a bed entry and exit routine. Data was collected using a pressure sensor array and video cameras. Lying and sitting postures...
In this paper, the Pareto optimum of the max-min beamforming problem with general power constraints is discussed. Conditions without a balanced signal to interference plus noise ratio are identified and based on the discussions an improved direct and iterative solution of the max-min beamforming problem is proposed. Numerical results show the performance gain of the presented solution compared to...
An accurate direction-of-arrival (DOA) estimation algorithm with sparse sensor array is proposed. By dividing the nonuniform linear sparse array (NLSA) into two uniform linear sparse arrays (ULSA), the subarray response vectors yield a property of rotational invariance in the estimation of rough DOA without ambiguity using the so-called generalized ESPRIT. According to the estimated rough DOA, the...
As the phased array radar works in a multi-objective environment, it's necessary to refer to the priority of targets when allocating resources during scheduling. The determination of priorities of targets needs to be fast and efficient, and consider multiple factors. Artificial neural network has adaptive and self-learning ability, and good fault-tolerance features, especially for processing problems...
A LED spectrum measurement system using a low-cost spectrum sensor array is proposed in this work. We note that since the spectral transmittance properties of the spectrum sensors are off ideal, a robust mapping process to transform the sensor outputs to the information of LED spectrum is demanded. For mapping the raw data from the low-cost spectrum sensor array to the spectrum component of LED lights,...
Derivation of monopulse angle accuracy for phased array radar to achieve Cramer-Rao lower bound is presented in this paper. Antenna element positions originating from antenna center are used for difference beam taper in this monopulse angle estimation. For uniform linear array, the accuracy is 1.16 times higher than conventional monopulse method. In other words, SNR can be reduced by 1.3 dB to achieve...
In this paper, we consider the direction of arrival (DOA) estimation problem under the coexistence of noncircular and circular signals. By exploiting the difference between the circularity of noncircular and circular signals, a method is proposed, which estimates the DOAs of noncircular and circular signals separately. The maximum number of detectable directions by the proposed method is twice that...
A new method for passive localization using an array sensor system based on spatial smoothing processing (SSP) with support vector machine (SVM) is proposed. The array sensor uses only one array antenna as the receiver to observe the signal subspace spanned by eigenvector through array signal processing. The signal subspace represents the radio wave propagation of interest. Based on the eigenvector,...
The intelligent robots which obtain their required information from the sensors and the precision instruments mostly have physical mistakes. In this research, first their common mistakes are analyzed, further an efficient model to decrease mistakes and reach to maximum accuracy is presented. This model ables to scan the entire 360 degree surroundings with accuracy using only one sensor, and after...
Recently, the development of mobile communications is making radio wave environments more complicated. To model radio wave environment appropriately, DOA (directions of arrival) estimation of individual incoming waves with array antenna is much effective [1]. For the purpose, many DOA estimation methods have been developed [1]. Among them, the high-resolution DOA estimation methods such as MUSIC and...
Direction-Of-Arrival (DOA) estimation is one of significant techniques for high-speed mobile communication to know wave propagation environment [1]. High resolution DOA estimation algorithms like MUSIC [2], and ESPRIT [3] have already been widely used in many wireless communication applications. Generally planar array structures are used for 2-D DOA estimation. Planar arrays often well estimate azimuth...
SUMWE (SUbspace-based Method Without Eigendecompositon) is one of the high-resolution DOA (Direction Of Arrival) estimation methods for coherent waves [1]. SUMWE employs spectrum peak search in DOA estimation like MUSIC method [2], that often leads large computational cost. Recalling that Root-MUSIC method [3] without spectrum peak search greatly reduces the computational cost, similar root-finding...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.