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Analysis of Margin Adaptive Resource Allocation in MIMO Systems

J. Ravindrababu, D. Swathi, P. Sameer Khan


Two types of multiuser resource allocation problems are referred as Margin Adaptive (MA) and Rate Adaptive (RA).  The  margin  adaptive  objective  is  to minimize  the  total  transmit  power  with  subject  to constraints  on  the  users'  data  rate  and  Bit  Error  Rate (BER). The rate adaptive aims to maximize the overall system capacity with a total power constraint. The main limitation of all these methods is that, in order to offer a minimum generalized degree of freedom per user, the required bandwidth must grow with the number of users. Another drawback of those techniques is Adaptive margin. In this paper to avoid those problems using two methods has been proposed. They are full CSIT (Channel State Information at Transmitter) and statistical CSIT. In both methods, a distributed convergence criterion for power control is determined and included within iterative power allocation. The proposed methods avoid power divergence situations at any load, and are consequently more efficient to solve the MA problem.


BER, Full Channel State Information Transmitter, Margin Adaptive and Rate Adaptive Problem.

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