Showing papers by "Alwyn J. Seeds published in 1992"
TL;DR: The first experimental demonstration of a heterodyne optical phase-lock loop (OPLL) using semiconductor lasers without external cavities or other linewidth narrowing methods was reported in this article.
Abstract: The first experimental demonstration is reported of a heterodyne optical phase-lock loop (OPLL) using semiconductor lasers without external cavities or other linewidth narrowing methods. For a total loop propagation delay of 3 ns and a loop filter bandwidth of 700 MHz, a phase error variance of 1.02 rad2 was achieved in 500 MHz measurement bandwidth.
183 citations
Journal Article•
22 citations
01 Dec 1992
TL;DR: In this paper, two novel approaches for the generation and distribution of reference and control signals for phased array antennas are proposed: a "nondispersive prism" and a "lens fed model array".
Abstract: Following an outline of established optical techniques for the generation and distribution of reference and control signals for phased array antennas, two novel approaches are put forward: (i) a ‘nondispersive prism’, controlling agile single beams or monopulse patterns, and (ii) a ‘lens fed model array’, which can control multiple, independent antenna beams. The prospects of fibre-optic transmission for other functions in the array are also considered.
20 citations
01 Aug 1992
TL;DR: In this article, a computer model for the performance of a semiconductor laser amplifier under static and dynamic input conditions is presented, where the model is used to study the behavior of the amplifier with sinusoidally intensity-modulated input signals.
Abstract: A computer model for the performance of a semiconductor laser amplifier under static and dynamic input conditions is presented. In particular, the model is used to study the behaviour of the amplifier with sinusoidally intensity-modulated input signals. The distortion arising from gain modulation at low modulation frequencies is investigated. It is shown that at microwave modulation frequencies the gain takes an average value and the response becomes linear. Semiconductor laser amplifiers are therefore suitable for applications in microwave optoelectronics, such as reference signal distribution in optically controlled phased-array antennas.
9 citations
01 Jun 1992
TL;DR: In this paper, a review of recent European work on components, subsystems, and applications of microwave optoelectronics is reviewed, with particular emphasis on areas, such as coherent techniques and the use of optical amplifiers, which are likely to have a strong impact on new system design.
Abstract: Recent European work on components, subsystems, and applications of microwave optoelectronics is reviewed, with particular emphasis on areas, such as coherent techniques and the use of optical amplifiers, which are likely to have a strong impact on new system design. Microwave optoelectronic components capable of operation well into the millimeter-wave region have been developed to commercial availability by a number of European manufacturers. Optical amplifiers seem likely to make microwave bandwidth networks with excellent signal to noise ratio a practical reality. Techniques for the generation of coherent optical signals have advanced substantially, so that it seems likely that coherent processing will become the preferred choice for optical beamforming in phase array antennas and many other signal processing applications. >
1 citations