On the Frequency-Selective Scheduling Gain in SDMA-OFDMA Systems

Details On the Frequency-Selective Scheduling Gain in SDMA-OFDMA Systems On the Frequency-Selective Scheduling Gain in SDMA-OFDMA Systems

2012-01-30

arxiv.org/abs/1201.6282v2

Computer Science

Networking and Internet Architecture

7 pages, 8 figures

Scientific paper

Orthogonal Frequency Division Multiple Access (OFDMA) is a multi-user version of the Orthogonal Frequency Division Multiplexing (OFDM) transmission technique, which divides a wideband channel into a number of orthogonal narrowband subchannels, called subcarriers. An OFDMA system takes advantage of both frequency diversity (FD) gain and frequency-selective scheduling (FSS) gain. A FD gain is achieved by allocating a user the subcarriers distributed over the entire frequency band whereas a FSS gain is achieved by allocating a user adjacent subcarriers located within a subband of a small bandwidth having the most favorable channel conditions among other subbands in the entire frequency band. Multi-User Multiple Input Multiple Output (MU-MIMO) is a promising technology to increase spectral efficiency. A well-known MU-MIMO mode is Space-Division Multiple Access (SDMA) which can be used in the downlink direction to allow a group of spatially separable users to share the same time/frequency resources. In this paper, we study the gain from FSS in SDMA-OFDMA systems using the example of WiMAX. Therefore, a complete SDMA-OFDMA MAC scheduling solution supporting both FD and FSS is proposed. The proposed solution is analyzed in a typical urban macro-cell scenario by means of system-level packet-based simulations, with detailed MAC and physical layer abstractions. By explicitly simulating the MAC layer overhead (MAP) which is required to signal every packed data burst in the OFDMA frame we can present the overall performance to be expected at the MAC layer. Our results show that in general the gain from FSS when applying SDMA is low. However, under specific conditions, small number of BS antennas or large channel bandwidth, a significant gain can be achieved from FSS.

Affiliated with

Also associated with

No associations

Rating

On the Frequency-Selective Scheduling Gain in SDMA-OFDMA Systems does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with On the Frequency-Selective Scheduling Gain in SDMA-OFDMA Systems, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and On the Frequency-Selective Scheduling Gain in SDMA-OFDMA Systems will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-360142