1. |
- Abrahamsson, R., et al.
(författare)
-
Elimination of leakage and ground-bounce effects in ground-penetrating radar data
- 2001
-
Ingår i: Proceedings of the 11th IEEE Signal Processing Workshop on Statistical Signal Processing, 2001. - 0780370112 ; , s. 150-153
-
Konferensbidrag (refereegranskat)abstract
- We address the problem of removing specular ground surface reflections and leakage/cross-talk from downward looking stepped frequency ground-penetrating radar (GPR) data. A new model for the ground-bounce and the leakage/cross-talk is introduced. An algorithm that jointly estimates these effects from collected data is presented. The algorithm has the sound foundation of a nonlinear least squares (LS) fit to the presented model. The minimization is performed in a cyclic manner where one step is a linear LS minimization and the other step is a non-linear LS minimization where the optimum can efficiently be found using, e.g., the chirp-transform algorithm. The results after applying the algorithm to measured GPR data, collected at a US army test range, are also shown
|
|
2. |
- Andersson, Tomas, et al.
(författare)
-
Frequency estimation utilizing the Hadamard transform
- 2001
-
Ingår i: 2001 IEEE WORKSHOP ON STATISTICAL SIGNAL PROCESSING PROCEEDINGS. - NEW YORK : IEEE. - 0780370112 ; , s. 409-412
-
Konferensbidrag (refereegranskat)abstract
- Fast analog to digital conversion with only one bit per sample does not only make high sampling rates possible but also reduces the required hardware complexity. For short data buffers or block lengths, it has been shown that tone frequency estimators can be implemented by a simple table look-up. In this paper we present an analysis of such tables using the Hadamard transform. As an outcome of the analysis, we propose a class of nonlinear estimators of low complexity. Their performance is evaluated using numerical simulations. Comparisons are made with the proper Cramer-Rao bound and with the table look-up approach.
|
|
3. |
- Athley, Fredrik, 1968
(författare)
-
Optimization of Element Positions for Direction Finding with Sparse Arrays
- 2001
-
Ingår i: Proc. 11th IEEE Signal Processing Workshop on Statistical Signal Processing, Singapore. - 0780370112 ; , s. 516-519
-
Konferensbidrag (refereegranskat)abstract
- Sparse arrays are attractive for Direction-Of-Arrival (DOA) estimation since they can provide accurate estimates at a low cost. A problem of great interest in this matter is to determine the element positions that yield the best DOA estimation performance. A major difficulty with this problem is to define a suitable performance measure to optimize. In this paper, a novel criterion is proposed for optimizing element positions. The ambiguity threshold of the Weiss-Weinstein Bound (WWB) is used to optimize the element positions of a sparse linear array. The array obtained from the optimization is compared with some other sparse array structures that have been proposed in the literature.
|
|
4. |
- Larsson, Erik G., et al.
(författare)
-
An algorithm for joint symbol timing and channel estimation for OFDM systems
- 2001
-
Ingår i: Proc. of IEEE Workshop on Statistical Signal Processing. 2001. - 0780370112 ; , s. 393-396
-
Konferensbidrag (refereegranskat)abstract
- We consider the problem of joint synchronization and channel estimation for orthogonal frequency division multiplexing (OFDM) systems. A new algorithm is proposed that estimates the channel and symbol timing simultaneously by using a technique based on maximum-likelihood (ML) theory and the generalized Akaike information criterion (GAIC). Finally, we demonstrate the performance of our algorithm by simulation results.
|
|
5. |
- Nordlund, Per-Johan, et al.
(författare)
-
A Framework for Particle Filtering for Positioning, Navigation and Tracking
- 2001
-
Ingår i: Proceedings of the 11th IEEE Signal Processing Workshop on Statistical Signal Processing. - : IEEE. - 0780370112 ; , s. 34-37
-
Konferensbidrag (refereegranskat)abstract
- A framework for positioning, navigation and tracking problems using particle filters (recursive Monte Carlo methods) is developed. Automotive and airborne applications, approached in this framework, have proven a numerical advantage over classical Kalman filter based algorithms. Here the use of non-linear measurement models and non-Gaussian measurement noise is the main explanation for the improvement in accuracy, and models for relevant sensors are surveyed.
|
|
6. |
- Svensson, Lennart, et al.
(författare)
-
Land mine detection in rotationally invariant noise fields
- 2001
-
Ingår i: SSP '2001. - Piscataway, NJ : IEEE Communications Society. - 0780370112 ; , s. 170-173
-
Konferensbidrag (refereegranskat)abstract
- This paper proposes a method to detect infrared land mine signatures embedded in rotationally invariant colored noise. A common problem in statistical image processing is high dimensionality. This causes a need for large sets of training data. To overcome this, an alternative formulation of the generalized likelihood ratio test (GLRT) is presented. This formulation makes it possible to utilize the circular-symmetry, rendering a substantial decrease in model dimensionality and consequently, in the amount of training data needed. Simulations indicate that a significant gain in performance can be achieved compared to both the non-parameterized detector and the matched filter.
|
|
7. |
- Völcker, Björn, et al.
(författare)
-
On design of correlation based frequency estimators
- 2001
-
Ingår i: 2001 IEEE WORKSHOP ON STATISTICAL SIGNAL PROCESSING PROCEEDINGS. - NEW YORK : IEEE. - 0780370112 ; , s. 425-428
-
Konferensbidrag (refereegranskat)abstract
- As a complement to the Periodogram, low complexity frequency estimators are of interest. Different designs of these estimators may affect the performance significantly. In this paper we consider correlation based estimators and present a design strategy that outperforms most estimators in the same class. We give a closed form expression for the asymptotic performance together with a new method of phase unwrapping to resolve an introduced frequency ambiguity. Finally, we illustrate the performance through a design example.
|
|