Mathematical model of nonlinear coupling and its effect on rotation sensitivity of semiconductor ring laser gyroscope

Radio frequency biosensing and all-optical devices

Abstract: Detecting presence of proteins in a given sample is an essential part of diagnostics. The use of the avidin–biotin interaction is becoming an increasingly common method for the detection of proteins. Among avidin group, Streptavidin forms strongest non-covalent biological interaction with biotin. Therefore, it is stable in wide range of temperatures and exhibits similar binding as antigen–antibody binding. The strong interaction has led to a large number of diagnostic applications using Streptavidin–Biotin technology. Permittivity of Biotin–Streptavidin combination shows a frequency dependency in several dispersion regions like regions. Traditional and standard biological testing use immunoassay technology (ELISA) method use chemicals, and molecules which modifies or destroy properties of sensing bio molecule are cumbersome (several reaction steps) and time consuming. We present design and development of the Bio Sensors using RF. On the other-hand, application of conventional electronic devices which are available commercially to optical signals is a current day challenge. As the output of these devices is bipolar it is difficult to apply to optical signals which are always positive or zero. Hence, developing devices with binary output is of great importance. It would be very interesting to design and develop all-optical devices using ring lasers for communication and computing applications. The design and modeling of various all-optical devices such as Gyroscope and Modulators has been proposed.

Diode Lasers and Photonic Integrated Circuits

Abstract: Ingredients. A Phenomenological Approach to Diode Lasers. Mirrors and Resonators for Diode Lasers. Gain and Current Relations. Dynamic Effects. Perturbation and Coupled--Mode Theory. Dielectric Waveguides. Photonic Integrated Circuits. Appendices. Index.

Long-wavelength semiconductor lasers

Abstract: The current status and future applications to lightwave transmission of long-wavelength semiconductor lasers emitting near 1.3 and 1.55- mu m are described. Bit-error-rate curves for a transmission experiment at 8 Gb/s over 76 km of fiber are shown, and schematics of a high-speed distributed feedback laser and a multielectrode distributed Bragg reflector laser are presented. >

An introduction to inertial navigation

Abstract: Until recently the weight and size of inertial sensors has prohibited their use in domains such as human motion capture. Recent improvements in the performance of small and lightweight micromachined electromechanical systems (MEMS) inertial sensors have made the application of inertial techniques to such problems possible. This has resulted in an increased interest in the topic of inertial navigation, however current introductions to the subject fail to sufficiently describe the error characteristics of inertial systems. We introduce inertial navigation, focusing on strapdown systems based on MEMS devices. A combination of measurement and simulation is used to explore the error characteristics of such systems. For a simple inertial navigation system (INS) based on the Xsens Mtx inertial measurement unit (IMU), we show that the average error in position grows to over 150 m after 60 seconds of operation. The propagation of orientation errors caused by noise perturbing gyroscope signals is identified as the critical cause of such drift. By simulation we examine the significance of individual noise processes perturbing the gyroscope signals, identifying white noise as the process which contributes most to the overall drift of the system. Sensor fusion and domain specific constraints can be used to reduce drift in INSs. For an example INS we show that sensor fusion using magnetometers can reduce the average error in position obtained by the system after 60 seconds from over 150 m to around 5 m. We conclude that whilst MEMS IMU technology is rapidly improving, it is not yet possible to build a MEMS based INS which gives sub-meter position accuracy for more than one minute of operation.

Photonic technologies for angular velocity sensing

Abstract: Photonics for angular rate sensing is a well-established research field having very important industrial applications, especially in the field of strapdown inertial navigation. Recent advances in this research field are reviewed. Results obtained in the past years in the development of the ring laser gyroscope and the fiber optic gyroscope are presented. The role of integrated optics and photonic integrated circuit technology in the enhancement of gyroscope performance and compactness is broadly discussed. Architectures of new slow-light integrated angular rate sensors are described. Finally, photonic gyroscopes are compared with other solid-state gyros, showing their strengths and weaknesses.