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This paper is mainly aimed at developing an advanced communication aid for the people having severe speech impairment. This method gives rise to a new form of communication aid which recognizes the disordered speech of the user and builds messages which are converted into synthetic speech. While employing this method, the recognition perplexity can be increased. The selected message building technique traded-off various factors including speed of message construction and range of available message outputs. The trial high lightened some issues which limit the performance and usability of device when applied in real usage situations, with mean recognition accuracy of 67% in these circumstances. A field trial by individuals with moderate to severe dysarthia and confined that they can make use of the device to produce intelligible speech output from disordered speech input.

This paper demonstrates the design and result of a low profile wide band miniaturized slit-loaded microstrip patch antenna with defected ground structures (DGS) for wireless applications. The proposed antenna is coaxially probe fed that operates at 5.5 GHz and has an array of rectangular slits etched on the patch and a pair of square-shaped dumbbell DGS loaded into the ground plane. The bandwidth of the slit-loaded microstrip patch antenna is 12 %, whereas it increases up to 17 % when DGS is loaded into the ground plane. The proposed compact antenna resonates at multiple frequencies between 1 and 9 GHz frequency range, at 4.84, 5.96, and 6.34 GHz with a bandwidth of 330, 150, and 460 MHz having return loss of −17.2, −18.5, and −27.3 dB, respectively. All the antenna geometries in this paper are simulated using an electromagnetic simulation tool named CADFEKO. The proposed multiband antenna finds useful applications with an improved performance simultaneously in W-LAN (4.8-5.8 GHz) and satellite communication bands (5.92-6.42 GHz). The plots of various antenna parameters such as return loss, voltage standing wave ratio (VSWR), gain, and bandwidth of the proposed antenna have been observed with and without DGS and the analysis of the simulated results shows that the proposed slit-loaded antenna with DGS is more efficient than conventional rectangular microstrip patch antennas (CRMPA) in terms of bandwidth of operation and miniaturization.