A folded reflectarray antenna with scanning beam ability is studied. In this configuration, the antenna waveguide feed position is shifted in x and y directions to tilt the antenna beam in E and H planes. The simulated results show that longer the shifted distances, the higher the tilted angle can be reached. The test antenna is designed at 60GHz. Index Terms -Folded reflectarray antenna, Beam scanning, Twist reflectarray, linear polarizing grid and rectangular waveguide.

Syngas from biomass residues is an alternative fuel to address the ever-increasing fossil fuel supply problem and the issue of releasing toxic gases from the fossil fuel burning process. Syngas is also a renewable fuel and features environmentally friendly fuel. This study was conducted to investigate the performance of the syngas produced from oil palm shells (PKS) using fluidized bed gasifier. In this study, the produced syngas was tested for its combustion performance from the aspect of gas combustion temperature and resulting emission concentrations such as nitrogen oxide (NOx), carbon monoxide (CO) and sulfur dioxide (SO2). The resulting syngas was studied at different ratio of air velocities to fuels. From the test, the ratio of velocity of air to fuel affects the gas combustion temperature and emission emission concentration. By increasing the air velocity to fuel ratio during the gasification process produces more positive effects primarily in improving the temperature of the gas burner combustion and reducing carbon monoxide (CO) emissions. However, the concentration of sulfur dioxide release (SO2) and nitrogen oxide (NOx) increase.