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We design a tapped-delay line (TDL) structured wide-band smart antenna array using vector-space projection (VSP) method. The structure consists of a one-dimensional antenna array with a TDL attached to each antenna. By controlling the weight coefficients at the TDL taps using VSP method, we achieve beamforming the array over wide frequency bands. Constraints and associated projections are furnished to meet the design specifications. We demonstrate the capability of VSP method adapted to solve this array design task. Index Terms--Broad-band operation, smart antenna arrays, tapped-delay line (TDL), vector space projections (VSP).

We use vector space projection (VSP) methods to design wide-band adaptive and self-healing arrays. Rectangular arrays are assumed but the VSP algorithm can be applied to any confirmation. In the VSP method, we formulate a set of design constraints and then iteratively improve on a trial solution by operations known as 'alternating projections.' When all of the constraint sets are convex and the intersection of these sets is not the empty set, we can meet the design specifications in a finite dimensional setting. In our simulations, we show that reasonable design constraints are readily met. We demonstrate that VSP is useful for broad-band self-healing, i.e., the reconfiguration of the array when some broad-band elements fail to operate. Finally we compare our results with a known design procedure for broadband antenna arrays. Index Terms--Broad-band operation, self-healing, smart antenna arrays, vector space projections (VSPs).

A new method of rejecting narrowband interference in direct-sequence spread spectrum (DS/SS) communications is presented. A typical approach is to reject the interference using a filter with large attenuation at the interference frequencies before despreading. The interference rejection method presented in this paper incorporates vector space projection techniques to suppress the correlated interference. Several signal characteristics are formulated which lead to constraint surfaces in the vector space of possible solutions. These constraint surfaces describe interference rejection solutions which introduce minimal distortion to the spread spectrum signal and simultaneously remove the interference. The constraint surfaces essentially correspond to spread spectrum signal estimates which, after interference rejection, conform to known characteristics of the transmitted spread spectrum signal. The formulation of the surfaces relies on prior knowledge about the spread spectrum signal correlation and spectral properties.

We address the problem of recovering a CT image from partial fan-beam data and prior knowledge. The method used is that of convex projections also known as the method of projections onto convex sets (POCS). We consider several incomplete-data geometries including those associated with limited source travel and beam-blocking internal opacities. To enable the recovery we use several prior-knowledge constraints including one associated with the directivity of the image vector. The overall recovery algorithm can be practically implemented by exploiting the Toeplitz structure of key operators.

Abstract - Photonics is becoming an increasingly important area of study for those involved in applications typically considered within the domain of electrical engineering. This report describes how the conventional undergraduate electrical engineering curriculum can accommodate, and be enriched by, an infusion of optical-related subjects., Electical engineering graduates with qualifications needed by the photonics industry can be produced by enriching the electrical engineering curriculum. Basic and elective courses on Photonics should be included in university and college curricula since Photonics is significant to the electrical engineering and not merely an applied technology which can be rendered obsolete in time. Photonics is applicable to several important areas such as computers, communications and circuits among others.

We consider the problem of reconfiguring array antennas whose performance has been degraded by the failure of one or more elements. We show that the method of vector-space projections is well suited for this task and enables the recovery of reasonable antenna performance when as many as 30% of the elements are inoperable. Index Terms--Antenna arrays, self-healing arrays, smart antennas, vector-space projections.

A new technique for designing linear and arbitrary-phase finite-impulse response (FIR) filters with various types of constraints is proposed. The approach is based on the method of vector space projections. We describe the constraint sets and their associated projections that capture the properties of the desired filters. In filter design, as in many other engineering problems, one is primarily interested in meeting design constraints, i.e., finding a feasible solution, not necessarily an optimum one. Vector space projection methods are well-suited for this purpose. We furnish numerous examples of FIR filter design by vector space projections, including the important and difficult arbitrary phase/magnitude problem. Examples that demonstrate the advantages and flexibility of this method over other known methods are furnished. Index Terms--All-pass filters, convex projection, FIR filters, linear and quadratic constraints.

We design a tapped-delay line (TDL) structured wide-band smart antenna array using vector-space projection (VSP) method. The structure consists of a one-dimensional antenna array with a TDL attached to each antenna. By controlling the weight coefficients at the TDL taps using VSP method, we achieve beamforming the array over wide frequency bands. Constraints and associated projections are furnished to meet the design specifications. We demonstrate the capability of VSP method adapted to solve this array design task. [ABSTRACT FROM AUTHOR]