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In this paper we will show the construction of acoustic active noise control in hear defenders by the help of Filtered-x Least Mean Squares structure and using a low power fixed point digital signal processor. This system is implemented for 20dB to 30dB attenuation of broad band noise and ca 60dB for sinusoidal interference. This is well suited for industrial applications.

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This paper mainly focuses on the throughput enhancement of legacy IEEE 802.11 MAC protocol. The two parameters, throughput and QoS are now main challenge for multimedia applications in wireless networks. Throughput parameter are very poor as compare with PHY data rate, even data rate goes infinite high. After certain PHY data rate, throughput are almost independent of data rate when data packets are fixed size. This is only due to large amount overhead adding with every data packets. So overhead reduction is the best solution to enhance the throughput for future communications. In this paper, I discussed two important overhead reduction mechanisms, which sufficiently improve the throughput performance. One is frame aggregation and another is block acknowledgement scheme. In performance analysis graph of both schemes, shows that the throughput performance are below 100 Mbps. But industries are seeking higher data rate for multimedia applications. i.e more than 100 Mbps. So it is easy make a comment that the above two important components are not sufficient enough for IEEE 802.11n individually. To fulfil the throughput performance of IEEE 802.11n, I proposed a new MAC mechanism. The new Frame Aggregation and BlockAcknowledgement (FABA) MAC mechanism is the collecting of some features of above two important components, which improve the throughput performance as our desire. In this research work I also simulate the FABA scheme, which shows the throughput performance more than 160 Mbps when the number of burst within TXOP duration is 5 and PHY data rate 600 Mbps.