In this paper new techniques that deal with the issue of spectrum management have to be developed. It is possible to increase the spectral efficiency by either shifting carrier frequencies closer together or altering the roll off factor .The second approach does not seems to be efficient than the first, due to increase in bandwidth, which leads to increase in noise, interference, multipath fading The first concept is able to control the Guard band dynamically. Possibilities to reduce the guard band between successive channels dynamically are to beinvestigated, thus improving spectral efficiency. This can be done efficiently by Multicarrier modulation Multicarrier modulation which has an ability to increase in the data rates and simultaneously we can decrease in the interference due to multipath fading channels. Multicarrier modulation schemes are of two types namely, Non-contiguous orthogonal frequency division multiplexing and Non-contiguous non orthogonal frequency division multiplexing. The proposed paper aims to investigate the various features of Multicarrier, Multipath system to address the challenges in wireless communications and provide a solution for the optimum utilization of the resources.

SRAM cells are used in many applications such as micro and multi core processor. SRAM cell improves both read stability and write ability at low supply voltage. The objective is to reduce the power dissipation of a novel low power 12T SRAM cell. This method removes half-select issue in 6T and 9T SRAM cell. This work proposes new functional low-power designs of SRAM cells with 6T, 9T and 12 transistors which operate at only 0.4V power supply in sub-threshold operation at 45 nm technology. The leakage power consumption of the proposed SRAM cell is thereby reduced compared to that of the conventional six-transistor (6T) SRAM cell. 12T cell obtains low static power dissipation.