10Gbps NRZ-DPSK repeaterless transmission system for terrestrial applications

We investigated the performance of 10Gbps NRZ-DPSK repeaterless transmission system over 300km. The system is demonstrated experimentally over standard Single-Mode Fiber (SMF). The results showed the capability of terrestrial repeaterless transmission systems as a cost effective solution for improving broadband penetration particularly for rural areas

Investigation on the microwave properties of kenaf and rice-husk fiber reinforced pla composite utilizing one-port coaxial transmission line reflection method

The paper investigates the microwave properties of natural fiber reinforced biodegradable plastic composites in order to recognize their potential as alternatives to common printed circuit board (PCB) for electronic communication industries. Thus, the paper reports on measured dielectric properties for two new composites under study: Kenaf/Poly Lactic Acid (PLA) and rice husk/PLA and their results are compared. The sample is made from equal weight percentage loading (50%wt - 50%wt) of kenaf and PLA. Another sample has also equal weight percentage loading (50% wt - 50%wt) of rice husk and PLA. The complex dielectric permittivity (ε = ε′ - jε″) and loss tangent (tan δ) of the two samples of natural fibers plastic composites have been studied in the frequency range of 500 MHz to 10 GHz. The dielectric permittivity is measured by scattering parameter (S-parameter) using a Vector Network Analyzer (VNA). The concentration dependence of permittivity and loss tangent is analyzed for each sample. It is observed that from 500 MHz to 3.32 GHz, real permittivity (ε′) values are consistent throughout the wide frequency range, at approximately 3.3. However, the permittivity seems to decrease at higher frequencies starting from 3.35 GHz for both samples, down to 2.5 at 10 GHz. Measured results show that kenaf/PLA mixture has higher permittivity (ε′) than the rice husk/PLA composite across the wide frequency range. Meanwhile, loss tangent (tan δ) is low and remains similar for both types of fiber compositions

Determination of the relationship between the moisture content and microwave dielectric properties in kenaf stem

A brief history of kenaf stem moisture content measurement by sensing the dielectric properties of kenaf stem is presented. The basic principles are also described for using microwave dielectric properties of kenaf stem for sensing moisture through their correlation with moisture content. Development of these techniques will provide useful instruments for on-line monitoring of moisture content in kenaf stem processing to separate between bast and core of kenaf stem and thus increase the quality of natural fibre, prevent spoilage in storage and transport, improve processing, and provide information important for yield determinations in precision agriculture applications

A dielectric composite and method for producing the same.

The present invention relates to a dielectric composite for electronic component comprising a fiber mixed with a polymer coated with a conductive material characterized in that the fiber is a natural fiber and method for producing the same. The natural fiber is an attractive option due to their relatively cheapness, ability to recycle, low density, biodegradable and low environmental concerns. Compared to synthetic fiber made from glass, carbon and steel, natural fiber has a high aspect ratio and high strength to weight ratio. The composite with low dielectric constant is suited for use in printed circuit boards (PCB) for high frequency, high speed application and low power consumption of circuits in electronic component. This factor contributes to produce a high performance electronic component