The study has proposed a novel and innovative system that uses image processing techniques for converting an imprinted Braille pattern into natural language character. The processing takes place through a series of steps implemented in MATLAB. The major step is the removal of noise from the scanned image of an imprinted Braille pattern and other artifacts and then segmenting the scanned image to yield lines. These segmented lines are then further processed to yield Braille characters. The complete system is fully tested and works efficiently for both manually written as well as computer generated Braille for Urdu language and is found to give accurate results. This novel idea can be implemented for any language, thereby has a profound positive impact on the development of education material for visually challenged individuals together with other applications.

General rightsThis document is made available in accordance with publisher policies. Please cite only the published version using the reference above. Full terms of use are available: http://www.bristol.ac.uk/pure/about/ebr-terms Abstract-This paper presents a detailed investigation into off-body links for wrist mounted Bluetooth Low Energy (BLE) devices for an indoor environment and revolves around three low profile antennas (microstrip patch, printed monopole and external monopole). It studies the received signal strength across different usage scenarios and obstructions such as body shadow, wall and ceiling through measurement campaigns carried out in a 2-storey house. It is observed that RSSIs show little variation from the mean value at any position in a given room of the house. In the living room, the average RSSI for patch, printed and external monopole is close to -61,-73 and -61 dBm respectively. The study describes the effect of usual obstructions such as wall and ceiling to off-body links and shows that the range of RSSI for any antenna (30 dBm at P=0.5 for Patch Antenna) is bounded at one end by the CDF of wall plus body shadow and at the other end by CDF of Line of Sight (LOS). The effect of body shadowing is studied in greater detail. It is observed that the microstrip patch antenna in LOS, under a ceiling and behind a wall, drops by approximately 15dB, 5dB and 10dB at P=0.4 when it goes into body shadow. The study also suggests that the Access Point (AP) on the ceiling provides better off-body links as compared to it in the adjacent room. The study compares the overall performance of the three antennas across all possible usage scenarios, obstructions & polarizations and concludes that the external monopole and patch antenna performs better than printed monopole by approximately 10-13 dBm. Finally, the study shows the variation of Packet Error Rate (PER) with RSSI and determines threshold values of RSSI for acceptable PERs, for reliable and robust applications.

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In this paper, an innovative and highly optimal triple layer Wireless Sensor Network (WSN) system is analyzed and illustrated, which monitors M-ary events like temperature, pressure, humidity, etc. with the help of geographically distributed local sensors. These local sensors are made to convey signals to the fusion centre using M-ary Frequency Shift Keying (MFSK) modulation scheme over Rayleigh fading channels. At the fusion centre, coherent detection aided by Maximal Ratio Combining (MRC) takes place. With the help of various simulations, the performance and efficacy of the system has been analyzed by varying modulation levels, number of local sensors and probability of correct detection by the local sensors. Our study endeavours to prove that MFSK WSN is a highly reliable system, which is capable of correct detection of M-ary events even if the channels are highly dynamic and the sensors are faulty.

In this paper, an innovative low complexity triple layer Wireless Sensor Network (WSN) system is proposed, which monitors M-ary events like temperature, pressure, etc. with the help of geographically distributed local sensors. These local sensors convey signals to the fusion centre using M-ary Frequency Shift Keying (MFSK) modulation scheme over Rayleigh fading channels. At the fusion centre, non coherent detection based on square-law principles aided by Equal Gain Combining (EGC) takes place. With the help of various simulations, the performance and effectiveness of the system has been analyzed by varying probability of correct detection by the local sensors, modulation levels and number of local sensors. Our study endeavours to prove that MFSK WSN is a dependable system, which can achieve reliable results for the correct detection of M-ary events even over a dynamic channel and with undependable sensors. Keywords-M-ary Frequency Shift Keying (MFSK), Wireless Sensor Network (WSN), Equal Gain Combining (EGC), Bit Error Rate (BER), Signal to Noise Ratio (SNR)