Engineering Commons^™

Optical Encryption As A Function Of Polarization In Optical Fiber Communications, Syed H. Murshid, Hari Priya Muralikrishnan, Jayachandran Tamilarasan, Abhijit Chakravarty, John H. Caulfield

Electrical Engineering and Computer Science Faculty Publications

An optical encryption technique based on polarization property of light is proposed. Many techniques using polarization beam splitters to encrypt the signal have been proposed earlier. They are based on splitting and interference of two light signals, namely message and noise. Only by placing suitable mirrors and a second beam splitter in a suitable position, the two signals are reconstructed at the output. In this paper we report the fiber optic version of a polarization based encryption technique that also has the potential to double the data carrying capacity of the fiber. Using polarization dependent couplers in the fiber optic …

Low Cost Electronically Steered Phase Arrays For Weather Applications, Mauricio Sanchez-Barbetty

Open Access Dissertations

The Electronically Steered Phased Array is one of the most versatile antennas used in radars applications. Some of the advantages of electronic steering are faster scan, no moving parts and higher reliability. However, the cost of phased arrays has always been prohibitive - in the order of $1M per square meter. The cost of a phased array is largely impacted by the cost of the high frequency electronics at each element and the cost of packaging. Advances in IC integration will allow incorporating multiple elements such as low noise amplifier, power amplifier, phase shifters and up/down-conversion into one or two …

Performance Enhancement Using Cross Layer Approaches In Wireless Ad Hoc Networks, Murad Khallid

USF Tampa Graduate Theses and Dissertations

Ad hoc network is intrinsically autonomous and self-configuring network that does not require any dedicated centralized management. For specialized applications such as, military operations, search-and-rescue missions, security and surveillance, patient monitoring, hazardous material monitoring, 4G (4th Generation) coverage extension, and rural communication; ad hoc networks provide an intelligent, robust, flexible and costeffective solution for the wireless communication needs.

As in centralized wireless systems, ad hoc networks are also expected to support high data rates, low delays, and large node density in addition to many other QoS (Quality of Service) requirements. However, due to unique ad hoc network characteristics, spectrum scarcity, …

Energy Band Engineering Using Polarization Induced Interface Charges In Mocvd Grown Iii-Nitride Heterojunction Devices, Neeraj Tripathi

Legacy Theses & Dissertations (2009 - 2024)

Characteristics of III-nitride based heterojunction devices are greatly influenced by the presence of high density of polarization induced interface charges. Research undertaken in the current doctoral thesis demonstrates the effect of presence of one, three and six sheets of polarization induced charges in three different III-nitride based devices, namely in a photocathode, a high electron mobility transistor (HEMT) and a hyperspectral detector structure. Through a systematic set of experiments and theoretical modeling an in-depth study of the interaction between multiple sheets of polarization induced charges and their impact on energy band profile was undertaken. Various device designs were studied and …