Browsing Faculty Research Publicatons by Issue Date
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Generalized array pattern synthesis by the method of alternating orthogonal projections
(1980)A geometric formulation of the "nullsteering" array antenna pattern synthesis problems for arbitrary array geometries is proposed. The formulation allows the use of some simple intuitive techniques for the construction ... 
Application of routh approximant method for reducing the order of a class of timevarying systems
(1980)A class of timevarying systems is considered for simplification, and a method is proposed to approximate a highorder timevarying system by a timeinvariant lower dimensional system. 
Simplified analytical procedure for fourelement nonuniformly spaced arrays
(1980)A simplified analytical procedure is suggested for the design of a fourelement symmetrical uniformly excited nonuniformly spaced linear antenna array. The errors resulting from the simplification are shown to be negligible ... 
Calculation of cutoff frequencies in optical fibers for arbitrary profiles using the matrix method
(1981)We here propose a simple numerical procedure to calculate the cutoff frequencies in optical fibers with any arbitrary refractive index profile including discrete numerical data from profile measurement. The cutoff problem ... 
FIR filter structures having low sensitivity and roundoff noise
(1981)A class of structures for FIR filters is presented, which exhibits reduced coefficient sensitivity and superior roundoff noise properties as compared to the direct form realization. It is shown that using fixedpoint ... 
Feedback communications over fading channels
(1981)A communication system using noiseless feedback for Rayleigh fading channels is proposed. Pilot tone signaling is used to provide channel amplitude and phase information for the detection of antipodal signals. Channel ... 
Propagation characteristics of single mode optical fibers with arbitrary index profiles: A simple numerical approach
(1982)We present here a rapidly converging numerical procedure for the direct evaluation of the propagation constant and its first and second derivatives in single mode optical fibers with arbitrary refractive index profiles. ... 
On the index for array optimization and the discrete prolate spheroidal functions
(1982)A class of array optimization problems is considered in which we seek to optimize the array response in a specified angular sector. The optimization of array directivity is shown to be a special limiting case of these ... 
FIR filter structures having low sensitivity and roundoff noise
(1982)A class of structures for FIR filters is presented, which exhibits reduced coefficient sensitivity and superior roundoff noise properties as compared to the direct form realization. It is shown that using fixedpoint ... 
Analytical approximations for the propagation characteristics of dualmode fibers
(1983)In this paper we present accurate analytical approximations for the modal fields of dualmode optical fibers with power law profiles based on a scalar variational analysis. We propose single parameter and two parameter ... 
Matrix method for determining propagation characteristics of optical waveguides
(1983)We have transformed the scalar wave equation into a matrix eigenvalue equation, the diagonalization of which gives the guided modes and a discrete representation of the radiation modes. The method is simple and can be used ... 
Invertibility of linear dynamical systems over commutative rings
(1983)This correspondence is addressed to the question of invertibility of linear dynamical systems. Specifically, inversion over principal ideal domains is discussed in view of the fact that 2D systems can be considered as 1D ... 
Linear phase IIR filter with equiripple stopband
(1983)A simple technique of introducing transmission zeros into a low pass allpole filter function to make its stopband transmission equiripple is described. The zeros are introduced through a transformation which maps the ... 
Performance degradation in fast frequencyscanned circular arrays
(1983)The performance deterioration that sets is when a circular array is scanned fast using the method of frequency scanning is considered. The highspeed effects are a loss in the mainbeam amplitude and a change in sidelobe ... 
An escalator structure for adaptive beamforming
(1983)The standard LMS algorithms for adaptive beamforming though straightforward, suffer from the main draw back of having slow, convergence rate. This is normally attributed to the wide range of spread of eigenvalues of the ... 
Sensitivity reduced optimal linear regulator with prescribed closedloop eigenvalues
(1984)In this note, the design technique given by Sebakhy and Sorial [1], based on both pole placement and optimal control, is extended to obtain a sensitivity reduced optimal linear regulator with prescribed closedloop ... 
Phase compensation of array dispersion effects for wideband signals
(1984)When a phased array is used in a large bandwidth system, such as a pulsecompression system, significant distortions can arise [1][4]. Apart from depending on array system parameters, such as aperture length, type of feed, ... 
On the constrained synthesis of array patterns with applications to circular and arc arrays
(1984)Synthesis of array patterns involving optimization with linear and nonlinear constraints is considered. The general solution for the composite weight vector can be decomposed into a part which satisfies the linear constraints ... 
Alternative lownoise realizations for narrowband recursive digital filters
(1984)Alternatives to Munson and Liu's structures [1] are given, which also realize a secondorder section having both poles and zeros, with low sensitivity and roundoff noise. Instead of realizing zeros separately from poles, ... 
Fading statistics of transhorizon microwave signals over a troposcatter path in northern India
(1984)An experimentel microwave troposcatter communication link established between the Indian Institute of Technology, Delhi, and the Central Electronics Engineering Research Institute, Pilani, is described. The link, which ...