Improved Dynamic Power Allocation Scheme for Massive Connectivity in NOMA System

Abstract

In a wireless network, the radio resources are allocated to the users based on the Orthogonal Multiple Access (OMA) technique. The performance of the network can be improved by introducing non-Orthogonal multiple access (NOMA) whenever the number of users increases tremendously. There is much scope in improving the outage probability, bit error rate (BER), high spectral efficiency and latency. To improve this, Non-Orthogonal Multiple Access (NOMA) technique has been discussed in this paper with fair power allocation technique. The effect of fixed power and dynamic power allocation has been discussed and compared, the Bit error rate (BER) and achievable rate have been analyzed and compared. The NOMA uses Successive interference cancellation (SIC) at the receiver for decoding the individual user’s data which is a complex process. The effect of imperfect SIC has also been evaluated and analyzed. In dynamic Power allocation technique higher power is devoted to the far users due to which the near user goes into outage. A new technique has been proposed to reduce the outage power while taking the target rate and SNR of each user into consideration. The results show an improvement in outage probability in comparison with the state of art technique.