Capacity Calculation and Sub-Optimal Power Allocation Scheme for OFDM-Based Systems

Somnath Das, Abhishek Chakraborty, Sanjay Kumar

Birla Institute of Technology, Mesra, Ranchi, India.

DOI: 10.4236/cn.2012.44034                

Abstract

For emerging cellular wireless systems, the mitigation of inter-cell interference is the key to achieve a high capacity and good user experience. This paper is devoted to the performance analysis of interference mitigation techniques for the downlink in an orthogonal frequency division multiple access (OFDMA) network, with a focus on the Long Term Evolution-Advanced (LTE-A) standard. Here we have derived a general closed-form equation of system capacity taking multiple cells into consideration and then we have investigated a coordination technique for interference mitigation. For the given interference constraint, how power should be transmitted into each OFDM sub-carrier for prevailing channel condition such that the total transmission rate of the base station can be maximized.

Keywords

Interference Reduction; LTE-A; OFDMA; Power Loading; System Capacity

Conflicts of Interest

The authors declare no conflicts of interest.

References

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