%0 Journal Article %1 harishkumargvenkatbabu2011dynamic %A Harish Kumar, G. Venkat Babu, Upadhayay M D %D 2011 %E Das, Dr.Vinu V %J International Journal on Communication %K Multiuser OFDM Sub-Channel %N 1 %P 4 %T Dynamic Sub-Channel Allocation in Multiuser OFDM Systems to Achieve Variable Data Rate %U http://doi.searchdl.org/01.IJCOM.2.1.162 %V 2 %X This paper investigates the problem of dynamic multiuser subchannel allocation in the downlink OFDM systems. In traditional TDMA or FDMA systems, resource allocation for each user is non-adaptively fixed. Since the subchannel allocations among the users are not optimized, a group of users is likely to suffer from poor channel gains resulting from large path loss and random fading. To resolve this problem a low-complexity adaptive subchannel allocation algorithm is proposed in this paper. By adaptively assigning frequency subchannels, n take advantage of channel diversity among users in different locations, which is called Multiuser diversity. The capacity of MU-OFDM is maximized when each subchannel is assigned to the user with the best channel-to- noise ratio for that subchannel. However, fairness among the users cannot generally be achieved with such a scheme. In this paper, a set of proportional fairness constraints is imposed to assure that each user achieve a required data rate, that ensures quality of service. In the proposed algorithm, subchannel allocation is performed by assuming an equal power distribution.

@article{harishkumargvenkatbabu2011dynamic, abstract = { This paper investigates the problem of dynamic multiuser subchannel allocation in the downlink OFDM systems. In traditional TDMA or FDMA systems, resource allocation for each user is non-adaptively fixed. Since the subchannel allocations among the users are not optimized, a group of users is likely to suffer from poor channel gains resulting from large path loss and random fading. To resolve this problem a low-complexity adaptive subchannel allocation algorithm is proposed in this paper. By adaptively assigning frequency subchannels, n take advantage of channel diversity among users in different locations, which is called Multiuser diversity. The capacity of MU-OFDM is maximized when each subchannel is assigned to the user with the best channel-to- noise ratio for that subchannel. However, fairness among the users cannot generally be achieved with such a scheme. In this paper, a set of proportional fairness constraints is imposed to assure that each user achieve a required data rate, that ensures quality of service. In the proposed algorithm, subchannel allocation is performed by assuming an equal power distribution. }, added-at = {2012-09-20T09:11:54.000+0200}, author = {{Harish Kumar, G. Venkat Babu}, Upadhayay M D}, biburl = {https://www.bibsonomy.org/bibtex/252cf8cb2beb838dd7f34a71035c87fbe/ideseditor}, editor = {Das, Dr.Vinu V}, interhash = {2059a5698aa04c65879f8462630621f6}, intrahash = {52cf8cb2beb838dd7f34a71035c87fbe}, journal = {International Journal on Communication}, keywords = {Multiuser OFDM Sub-Channel}, month = {march}, number = 1, pages = 4, timestamp = {2012-09-20T09:11:54.000+0200}, title = {Dynamic Sub-Channel Allocation in Multiuser OFDM Systems to Achieve Variable Data Rate }, url = {http://doi.searchdl.org/01.IJCOM.2.1.162}, volume = 2, year = 2011 }