A parasitic patch loaded staircase shaped UWB MIMO antenna having notch band for WBAN applications

A staircase-shaped quasi-fractal antenna is presented to meet the requirements of compact electronics operating in UWB or E-UWB spectrum. A conventional broadband monopole antenna is converted into UWB antenna utilizing three iterations of fractal patches. The resultant antenna offers wide impedance bandwidth ranges 2.3–17.8 GHz, having a notch band at 6.1–7.2 GHz. Afterwards, a two-port MIMO antenna is created by placing the second element orthogonally with an edge-to-edge distance of 8.5 mm, that is λ/15 where λ corresponds to free space wavelength at the lowest cut-off frequency. Hereafter, a meandered line-shaped stub is inserted to reduce the mutual coupling between closely spaced MIMO elements to less than −25 dB. As the intended application of the proposed work is On-body, Specific Absorption Rate (SAR) analyses are carried out at 2.4, 5.8 and 8 GHz, showing an acceptable range for both 1-g and 10-g averaged tissues standards. Moreover, various parameters of the MIMO antenna are studied, and a comparison is made between simulated and measured results as well as those of the state of the art

"Development of wireless fire products”

The project was to develop a radio controlled door holder system as the first in a range of radio based products for Stephenson Gobin Eng Co. Ltd. Stephenson Gobin manufacture and market a wide range of electromechanical products, including retaining devices for fire doors and smoke vents. Typical installations are in hospitals, nursing homes, shopping centers, hotels or any building open to the public. The author discusses why a radio controlled door holder system is commercially and technically viable. Various wired and Wirefree door holder systems are evaluated on merits of safety and ease of installation. Stephenson Gobin developed a bi-stable latching door holding device which consumed no current in a state that was capable of holding a fire door open. This was due to a rotating magnetic slug assembly which only drew current to latch from one state to other. The device needed to be controlled wirelessly and possible methods of communication were assessed. Communicating using the license free radio frequency spectrum was selected due to the falling costs of radio components and the huge growth in the radio communication sector. The author developed and tested the hardware and software necessary to communicate with and actuate such a device