Field Transmission using Fiber Bragg Grating-based Dispersion Compensating Modules with Continuous Response over the Full C-band
Fiber Bragg grating-based dispersion compensating modules with continuous response over the full C-band are demonstrated. Group delay characteristics are analysed and modules are used in 10-Gbit/s and 40-Gbit/s field experiments over 820 km installed fiber.
16 x 10 Gb/s WDM transmission over 840-km SMF using eleven broad-band chirped fiber gratings
We demonstrate wavelength-division-multiplexed transmission of 16 10-Gb/s nonreturn-to-zero channels with 50-GHz spacing over 840 km of conventional single-mode fiber (SMF), or 14 times the 10-Gb/s dispersion limit, using a total of eleven chirped fiber gratings for dispersion compensation. Each grating has a nominal dispersion of -1330 ps/nm km for compensating 80 km of SMF and a bandwidth of 6.5 nm, and one grating has additional dispersion slope compensation of -35 ps/nm/sup 2/ equivalent to 480 km of SMF. The large number of closely spaced wavelengths and long transmission distance significantly stress the wavelength uniformity, bandwidth, and cascadability of the fiber gratings.
Microwave source with enhanced radiation power based on orbitron MASERs
We have proposed the design of high power microwave source in a vacuum tube based on the theory of negative mass instability. The proposed source does not operate based on a slow-wave structure but instead makes use of accelerated charged particles. In our structure, an electron emitter injects the charged particles into to the cavity. Emitted particles move around the anode, which leads to electron acceleration and emission of electromagnetic waves with a specific frequency. In this paper, we have enhanced the output power and frequency of microwave source by variation of particles initial energy and the number of anodes incorporating their specific arrangement and applied voltages. Working at room temperature, compactness, wide bandwidth, and tunability of output frequency are among the advantages of the proposed source.