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Summary: Pilot contamination has come up as one of the major limitations of massive multiple‐input multiple‐output. In the recent past, the pilot contamination resulted by the pilot reuse in inter‐cell system has been successfully handled. In this paper, three efficient algorithms have been proposed to reduce the pilot contamination in intra‐cell system. These schemes emphasize on assigning the available pilots to the users based upon their channel qualities by considering the interfering degree of the various pilot sequences. The first proposed algorithm is based on water filling approach, which attains the system throughput very close to that of brute‐force exhaustive search algorithm (ESA) and performs the best among the three proposed algorithms in terms of system throughput. The second algorithm is designed for achieving better user fairness (by assigning less interfering pilots to the poor channel conditioned users). The third algorithm improves the system throughput as compared to the second algorithm without losing much in terms of user fairness. Furthermore, the computational complexity incurred by all the proposed algorithms is much less than that of ESA. [ABSTRACT FROM AUTHOR]

Carrier frequency offset (CFO) results in multiaccess interference and intersymbol interference and degrades the bit error rate performance. Mitigating the effects of CFO always burdens the receiver with respect to architecture and power. This disadvantage increases with increase in number of users. In the present work, bit error rate analysis of multiuser group orthogonal-orthogonal frequency division multiple access scheme for variable rate and single rate over pedestrian channel in the presence of CFO is presented. Through analysis, it is proved that by incorporating carrier interferometry codes in the scheme, CFO effects can be removed without burdening receiver. It is also shown by analysis that effect of CFO is rate dependent. Finally, simulation results are provided to confirm the analytical results. [ABSTRACT FROM AUTHOR]