Showing papers by "Alwyn J. Seeds published in 1995"
TL;DR: The problem of beam squinting in phased arrays is analyzed and the concept of true-time delay is introduced, and the advantages of realizing variable delay lines by optical rather than by microwave means are reviewed.
Abstract: This tutorial review paper deals with various methods for solving a basic problem of wideband phased arrays, i.e. beam squinting, using optical technologies. The problem of beam squinting in phased arrays is analyzed and the concept of true-time delay is introduced. The advantages of realizing variable delay lines by optical rather than by microwave means are reviewed, together with principles of operation. Among the techniques described are switched-path length delay lines, fiber stretchers, tunable lasers with highly dispersive fiber, and coherent techniques incorporating dispersive delay. Recent experimental results are discussed in the light of practical system requirements. >
230 citations
07 Aug 1995
TL;DR: In this article, the noise and stability problems of this approach were studied and the output of two or more DFB lasers injection locked to the same optical comb was analyzed. But the authors did not consider the effect of the DFB laser injection on the stability of the system.
Abstract: Microwave frequency synthesis can be realised by mixing the output of two or more DFB lasers injection locked to the same optical comb. The noise and stability problems of this approach are studied.
20 citations
TL;DR: Reflection spectrum tuning of InGaAsP/InP asymmetric Fabry-Perot modulators using anodic oxidation followed by anodic oxide removal is reported for the first time in this article.
Abstract: Reflection spectrum tuning of InGaAsP/InP asymmetric Fabry-Perot modulators (AFPMs) using anodic oxidation followed by anodic oxide removal is reported for the first time. 30-40 nm tuning of the reflection spectra of double and single Bragg stack mirror AFPM structures with better than lambda /100 accuracy has been achieved. >
5 citations
01 Dec 1995
TL;DR: In this paper, the noise and stability problems of this approach were studied and the output of two or more DFB lasers injection locked to the same optical comb was analyzed. But the authors did not consider the effect of the DFB laser injection on the stability of the system.
Abstract: Microwave frequency synthesis can be realised by mixing the output of two or more DFB lasers injection locked to the same optical comb. The noise and stability problems of this approach are studied.
2 citations
01 Dec 1995
TL;DR: In this article, a simple method of generating microwave signals by using a single DFB laser integrated with an extended cavity is presented, achieving high spectral purity by locking to harmonics of an electrical drive signal applied to the laser bias current.
Abstract: A simple method of generating microwave signals by using a single DFB laser integrated with an extended cavity is presented. High spectral purity is achieved by locking to harmonics of an electrical drive signal applied to the laser bias current.
07 Aug 1995
TL;DR: In this article, a simple method of generating microwave signals by using a single DFB laser integrated with an extended cavity is presented, achieving high spectral purity by locking to harmonics of an electrical drive signal applied to the laser bias current.
Abstract: A simple method of generating microwave signals by using a single DFB laser integrated with an extended cavity is presented. High spectral purity is achieved by locking to harmonics of an electrical drive signal applied to the laser bias current.