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.
In wireless communications, the signal that a base station receive cannot be regarded as a point source because of the multipath propagation. A distributed source model is more suitable for the realistic scenario due to some environmental phenomenon. This paper presents subspace based method for distributed source direction of arrival estimation. Using nested sparse circular arrays, we are capable...
In this paper, we present a simplified mutual coupling matrix (MCM) for Sparse Circular Arrays (SCA) that is used for underdetermined direction of arrival (DOA) estimation. The array type used in this paper is composed of dense and sparse parts that obtains very low mutual coupling (MC). This leads to a banded-like MCM. By incorporating the MCM in the DOA estimation problem, SCA is capable of DOA...
This paper presents a novel array configuration which improves the accuracy for high-resolution direction of arrival (DOA) estimation using the concept of Khatri-Rao (KR) product. We extended the concept of two-level nested array and found a novel array configuration which has larger array aperture and more degree of freedom compared with that of the two-level nested array. The performance of the...
This paper proposes a novel sparsity-aware method that can estimate more sources than the number of sensors available based on the I1 optimization technique. This approach enforces sparsity by £1 penalization and restricting error by £2-norm which enables the reconstruction of sparse signals. By using the Khatri-Rao (KR) subspace approach, we obtain an increase in the degrees of freedom (DOFs). Thus,...
This paper presents a radio-based real-time moving object tracking method based on Kalman filtering using phase-difference compensation technique and nonuniform pulse transmission scheme. Conventional methods often require time, amplitude, phase information and their derivatives for each receiver antenna, however its location estimation accuracy does not become good even with many transmitting pulses...
This paper presents an accurate, radio-based and real-time moving object tracking method and its application to sports analysis. The present tracking method is based on Kalman filtering using a phase difference compensation technique and a non-uniform pulse transmission scheme. Conventional Kalman-based tracking methods often require time, amplitude, phase information and their derivatives for each...
This paper presents a novel array configuration based on the combination of the sum and difference co-arrays. There have been many studies on the array antenna configurations which enhances the array degree of freedom (DOF), however the maximum DOF of the configurations based on the difference co-array is often limited. We try to further enhance the DOF by combining the concepts of the sum coarray...
This paper presents an optimum linear array geometry for 2q-th order cumulant-based array processing for high-resolution direction of arrival (DOA) estimation. The concept of Khatri-Rao (KR) product gives the difference co-array which makes larger virtual array aperture. The virtual array geometry depends on the original physical array configuration, and the minimum redundancy array (MRA) can be regarded...
In this paper, the problem of direction-of-arrival (DOA) estimation for quasi-stationary signals is addressed using non-uniform circular arrays called nested circular array. We use the Khatri-Rao (KR) subspace approach to obtain an increase in the degrees of freedom. Thus, the nested circular array is capable of resolving more sources than the number of sensors. We therefore perform overdetermined...
This paper presents a weighted version of shooting method for high-resolution Direction Of Arrival (DOA) estimation based on Sparse Spectrum Fitting (SpSF). SpSF is one of the sparse DOA estimation methods based on ℓ1-regularization which uses the penalty term in optimization. The regularization process often takes long time and is very sensitive to the penalty term, but it is difficult to know its...
This paper presents a radio-based real-time moving object tracking method based on Kalman filtering using phase-difference compensation technique and nonuniform pulse transmission scheme. Conventional Kalman-based tracking methods often require time, amplitude, phase information and their derivatives for each receiver antenna, however its location estimation accuracy does not become good even with...
Automatic speech recognition for real-world applications such as a robot should deal with speech under noisy environments. This paper presents coarse phoneme recognition which uses a phoneme group instead of a phoneme as a unit of speech recognition for such a real-world application. In coarse phoneme recognition, the design of the phoneme group is crucial. We, thus, introduce two types of phoneme...
This paper presents multiple snapshot spatial smoothing with improved aperture (MS-SSIA) for high-resolution direction of arrival (DOA) estimation by uniform linear array (ULA). Spatial smoothing preprocessing (SSP) is often used for DOA estimation of correlated sources, but it reduces the effective array aperture and leads to low DOA estimation accuracy. SSIA is a method that solves this SSP problem;...
This paper presents a computationally efficient Direction-Of-Arrival (DOA) estimation method for Uniform Rectangular Array (URA), which is effective for both correlated and uncorrelated sources. The proposed method is an extension of our previous study for Uniform Linear Array (ULA), basically based on the relation between the elements of array covariance matrix, does not need iteration, angular peak-search...
This paper presents a novel coding tree depth estimation method for H.265/HEVC using neighboring block information. There have been some complexity reduction methods for H.265/HEVC by estimating coding tree structure from neighboring blocks, while preserving almost the same image quality and compression rate. The coding tree structure is not estimated for all the frames, its interval is determined...
This paper presents an accurate source number detection method for low-cost array system based on nested array and Khatri-Rao product approaches. Source number estimation accuracy can be enhanced by increasing the number of array elements, but it is often limited due to hardware and software cost. The authors have already proposed a low-cost array receiver system using switches which can reduce receiver...
A simple discrete version of B-splines is proposed. The proposed discrete version has different values from B-splines at the discrete points, but it is proven that the proposed discrete version tends to B-splines when the sampling interval goes to zero. They can be evaluated more quickly than the former discrete B-splines, only by RRS digital filters.
This paper proposes a high-resolution DOA (Direction Of Arrival) estimation method using GROUSE and EM algorithms for low-cost array antenna system. The low-cost array antenna system, which uses less receiver modules than array elements, often leads worse DOA estimation accuracy when comparing with the full-cost array antenna system. The proposed method first employs the modified GROUSE algorithm...
This paper presents a computationally efficient Direction-Of-Arrival (DOA) estimation algorithm by Uniform Linear Array (ULA), which is effective for highly-correlated sources but also works for uncorrelated sources. The proposed algorithm is basically based on the relation between the elements of array covariance matrix, does not need eigendecomposition, iteration or angular peak-search, and leads...
This paper presents a method of synthesizing covariance matrix elements of array input signal based on the relation between the relative location of array elements for high resolution 2-D Direction-Of-Arrival (DOA) estimation. Antenna array generally has the same number of array elements and receiver modules which often leads large receiver hardware cost. The authors have already studied a way of...
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.