Showing papers on "Automatic target recognition published in 1979"
TL;DR: In this paper, a convolve-and-backproject (CBP) algorithm is proposed to estimate the shape of a target in a 3D space around the target, where the measurements are taken by radars located in 3D spaces around the object region.
Abstract: The problem of radar target-shape estimation for perfectly conducting complex objects is formulated as an image-reconstruction problem. A convolve-and-backproject algorithm is derived when the measurements are taken by radars located in three-dimensional space around the object region. The algorithm can be used directly in that there are no restrictions on the sensor placement; the sensors are not required to lie in a plane, for example, as is often assumed in many applications. Two possible convolving functions with desirable implementation characteristics are described. The algorithm is applicable to the general problem of reconstructing the density function of three-dimensional objects and applies to the radar shape-estimation problem as a special case.
27 citations
TL;DR: In this article, the upper sideband of a sampled-speech signal with the original baseband signal for further signal processing is enhanced by shifting both bands to form a continuum from 0 Hz to the sampling frequency.
Abstract: Signal-to-noise is enhanced by including the upper sideband of a sampled-speech signal with the original baseband signal for further signal processing. The invention features shifting both bands to form a continuum from 0 Hz to the sampling frequency. Application in a speech recognition is shown.
25 citations
2 Apr 1979
TL;DR: The results show that target recognition is feasible with either of the methods tested, and 100 percent correct recognition is achieved with 15 parameters when no noise is added to the test echoes.
Abstract: This paper presents results of an experiment to determine the feasibility of an active sonar target recognition system. Echo data from 16 targets of maximum dimension 12 inches were obtained in a salt water pool. The target frequency responses in the 15-45 kHz band were used to characterize the targets. Pattern recognition techniques were applied to define and test two recognition methods. The results show that target recognition is feasible with either of the methods tested. 100 percent correct recognition is achieved with 15 parameters when no noise is added to the test echoes. If white noise is added to the test echoes, accuracy is well above 90 percent provided the signal-to-noise ratio is at least 5 dB.
8 citations