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Gradient estimation for stochastic optimization of optical code-division multiple-access systems. II. Adaptive detection
(IEEE, 1997-05-20)
For pt.I see ibid., vol.15, no.4, p.731-41 (1997). We develop infinitesimal perturbation analysis (IPA)-based stochastic gradient algorithms for deriving optimum detectors with the average probability of bit error being ...
Multiuser receivers for code-division multiple-access systems with trellis-based modulation
(1996-10-20)
A code-division multiple-access (CDMA) communication system is studied where a trellis-based scheme is used for data encoding and modulation. The signature sequences (spreading codes), which are assigned to the direct-sequence ...
3-D segmentation and volume estimation of radiologic images by a novel, feature driven, region growing technique
(1992)
Magnetic Resonance (MR) imaging is a 3-D, multi-slice, radiological technique that acquires multiple intensities corresponding to each voxel. The transverse relaxation time, T$\sb1$, and the axial relaxation time, T$\sb2$, ...
A multiuser receiver for code division multiple access communications over multipath channels
(1995-02-20)
A multiuser communication system is considered where K users share a channel with multipath propagation by using code division for multiple access. Data modulation is carried out by binary phase shift keying and direct ...
Delay and DOA estimation in CDMA communication systems via maximum likelihood techniques
(1997-10-20)
We present a maximum likelihood method for delay estimation in a CDMA wireless communication system. An antenna array is used at the receiver, which facilitates the concomitant estimation of the direction of arrival (DOA) ...
Stabilization and throughput of spread spectrum multiple access systems with multiple reception capability
(1992)
The task of stabilizing communication networks sharing a spread spectrum channel is addressed. A slotted system is considered and the stabilization is achieved by controlling the number of packets that are transmitted in ...
Wavelet Based SAR Speckle Reduction and Image Compression
(1995-01-15)
This paper evaluates the performance of the recently published wavelet based algorithm for speckle reduction of SAR images. The original algorithm, based on the theory of wavelet thresholding due to Donoho and Johnstone, ...
A Simple Covariance Based Characterization of Joint Signal Representations of Arbitrary Variables
(1996-01-20)
Joint signal representations of arbitrary variables extend the scope of joint time-frequency representations, and provide a useful description for a wide variety of nonstationary signal characteristics. Cohen's marginal-based ...
Design of Linear Phase Cosine Modulated Filter Banks for Subband Image Compression
(1994-01-15)
Wavelet methods give a flexible alternative to Fourier methods in non-stationary signal analysis. The concept of band-limitedness plays a fundamental role in Fourier analysis. Since wavelet theory replaces frequency with ...
Allpass Filter Design and Applications
(1995-01-15)
The Problem of allpass filter design for phase approximation and equalization in the Chebyshev sense is solved by using a generalized Remez algorithm. Convergence to the unique optimum is guaranteed and is achieved rapidly ...