A novel adaptive beamforming method is proposed without the knowledge of the direction of arrival of the signal of interest. It is a combination of the traditional beamspace processing method and a recently proposed t...
详细信息
ISBN:
(纸本)9781424422401
A novel adaptive beamforming method is proposed without the knowledge of the direction of arrival of the signal of interest. It is a combination of the traditional beamspace processing method and a recently proposed technique called "Domain Weighted Principal Component Analysis (DW-PCA)" and can be applied to the case where the signal of interest is stronger than the interfering signals in both single-path and multi-path environments. Its effectiveness is verified by simulation results.
This paper is concerned with the problem of antenna array calibration in a non-stationary signal environment. In detail, this study focuses on calibration of the antenna array geometry by employing properties of the d...
详细信息
ISBN:
(纸本)9781424422401
This paper is concerned with the problem of antenna array calibration in a non-stationary signal environment. In detail, this study focuses on calibration of the antenna array geometry by employing properties of the differential geometry of the array manifold vector. The proposed algorithm is totally blind, since the only available information to the array system is the received signal emitted by a moving source of unknown characteristics. The only assumption made is that the movement of the source has an angular component and that the position of one sensor with regards to the reference point is known. It is shown through Monte Carlo simulations that this method significantly improves the ability of the array system to estimate characteristics of the moving source, such as its direction of arrival (DOA), in addition to reducing the positioning errors of the array elements.
This paper is devoted to under-determined linear mixtures of independent random variables (i.e. with more inputs than outputs). Blind identifiability of general under-determined mixtures is first discussed, and the ma...
详细信息
ISBN:
(纸本)0780385454
This paper is devoted to under-determined linear mixtures of independent random variables (i.e. with more inputs than outputs). Blind identifiability of general under-determined mixtures is first discussed, and the maximum number of sources is given, depending on the hypotheses assumed. Then an algorithm proposed by Taleb, essentially usable for 2-dimensional mixtures, is extended to the complex field. A procedure is proposed in order to avoid the enormous increase in complexity. Computer simulations demonstrate the ability of the algorithm to identify mixtures of N QPSK sources received on 1 or 2sensors.
This paper presents a novel synthetic aperture method, which can be used to reduce the average sidelobe level of a random spherical volumetric array. The technique exploits a general property of random arrays in which...
详细信息
ISBN:
(纸本)1424403081
This paper presents a novel synthetic aperture method, which can be used to reduce the average sidelobe level of a random spherical volumetric array. The technique exploits a general property of random arrays in which the average sidelobe level is inversely proportional to the number of elements present.
The design of frequency invariant beamformers for traditional tapped delay-line array system can be formulated as a convex optimization problem and solved efficiently using the interior-point methods. This approach is...
详细信息
ISBN:
(纸本)9781424422401
The design of frequency invariant beamformers for traditional tapped delay-line array system can be formulated as a convex optimization problem and solved efficiently using the interior-point methods. This approach is extended to the recently proposed broadband beamforming system with sensor delay-lines and some variations are proposed to cope with the specific requirements in the design. Design examples are provided to show the effectiveness of the proposed method.
Autofocus is imperative for inverse synthetic aperture radar (ISAR) imaging. In this paper an approach for ISAR autofocus is developed by use of second order statistics (SOS) of returned signals. The ISAR observation ...
详细信息
ISBN:
(纸本)0780385454
Autofocus is imperative for inverse synthetic aperture radar (ISAR) imaging. In this paper an approach for ISAR autofocus is developed by use of second order statistics (SOS) of returned signals. The ISAR observation model is established, the approach is verified and the relationship of the developed approach to other methods is investigated. The results of processing real data confirm the validity of proposed approach.
We consider the problem of achieving high data rates for uplink transmission on multi-input, multi-output (MIMO) channels. We propose a soft decision space-time detection scheme of linear complexity in a turbo-coded a...
详细信息
ISBN:
(纸本)0780385454
We consider the problem of achieving high data rates for uplink transmission on multi-input, multi-output (MIMO) channels. We propose a soft decision space-time detection scheme of linear complexity in a turbo-coded architecture with a new form of iterative processing. Simulation results illustrate that the coded MIMO system is within 1.5 dB of the Shannon capacity limit on uncorrelated flat Rayleigh fading MIMO channels, where the receiver only possesses channel state information.
Conventional MUSIC (MUltiple signal Classification)rraethod, which is a well-known super-resolution technique that employs amonostatic configuration, degrades severely when themultiple targets are deterministic becaus...
详细信息
ISBN:
(纸本)1424403081
Conventional MUSIC (MUltiple signal Classification)rraethod, which is a well-known super-resolution technique that employs amonostatic configuration, degrades severely when themultiple targets are deterministic because the rank of the covariancematrix collapses to the value of one regardless of the number of targets. FRM (Frequency Response Matrix) [2, 7], with its multistatic configuration, is also a super-resolution technique and can complament, MUSIC in the target randomness spectrum. This paper demonstrates that conventional MUSIC performs better for targets with strongly random (complex) amplitudes and FRM performs better for target with weakly random amplitudes (best for deterministic amplitudes).
This paper presents a new methodology for airborne wideband space-time adaptive processing (W-STAP) radar systems. In W-STAP, the wideband target signal is first decomposed into a series of narrowbandsignals. This is...
详细信息
ISBN:
(纸本)0780385454
This paper presents a new methodology for airborne wideband space-time adaptive processing (W-STAP) radar systems. In W-STAP, the wideband target signal is first decomposed into a series of narrowbandsignals. This is referred to as a sub-banding process. The different signals are then combined into a single reference sub-band (usually the center). STAP processing is then performed at this reference band. The combination process is done through a transformation from the different sub-bands into the reference one using the focusing approach [1]. In this method, non-sinaular transformation matrices are used. Compared to the conventional approach proposed in [2], the focusing technique provides greater Computational efficiency in wideband STAP systems.
For a set of T independent N-variate Gaussian training samples (T < N), we derive a test for discriminating between stationary autoregressive models of order m, AR(m), and time-varying autoregressive models of orde...
详细信息
ISBN:
(纸本)1424403081
For a set of T independent N-variate Gaussian training samples (T < N), we derive a test for discriminating between stationary autoregressive models of order m, AR(m), and time-varying autoregressive models of order m, TVAR(m).
暂无评论