Two-dimensional downlink burst construction in IEEE 802.16 networks

Abstract

Several burst construction algorithms for orthogonal frequency division multiple access were proposed. However, these algorithms did not meet the downlink burst characteristics specified in the IEEE 802.16 standard. This article therefore proposes the best corner-oriented algorithm (BCO). BCO not only complies with downlink burst characteristics, but also considers the three issues to obtain high throughput, as follows: BCO maintains all free slots as a continuous area by constructing each burst in the corner of the available bandwidth area for minimizing external fragmentation; BCO shrinks the burst area to minimize internal fragmentation, if the requested bandwidth has been satisfied; and for exploring the continuous subchannels with good channel quality, BCO ensures that the burst adopts an optimal modulation coding scheme by selecting the excellent corner that can generate the maximal throughput. The simulation results indicate that BCO achieves 2-9 times the throughput achieved by the previous algorithms under a heavy load.

A best block exploring algorithm for two-dimensional downlink burst construction in IEEE 802.16 networks

“…However, traditional studies in the field of Operational Research are not applicable to burst construction because they focus on packing objects with fixed shapes and values (Hopper and Turton, 2001;Pisinger and Sigurd, 2005;Egeblad and Pisinger, 2009). Thus, many algorithms have been proposed (Ben-Shimol et al, 2006;So-In et al, 2009;Wang et al, 2008;Shih et al, 2010;Cicconetti et al, 2011;Lai and Chen, 2012;Sarigiannidis et al, 2010;Erta et al, 2007;Ohseki et al, 2007;Lee et al, 2011;Cicconetti et al, 2010;Eshanta et al, 2011;Liang et al, 2011;Baek and Suh, 2012;Vanderpypen and Schumacher, 2011;Chen et al, 2011;Nusairat, 2012;Lai and Chen, 2011) and grouped into uplink burst and downlink burst construction algorithms. Raster, BandAMC, and the method that we developed elsewhere are methods of constructing multi-rectangular uplink bursts (Ben-Shimol et al, 2006;Cicconetti et al, 2011;Lai and Chen, 2012).…”

“…BCM was also designed in a similar manner to the design of CDBA, but it sacrificed some throughput for reducing computational complexity (Nusairat, 2012). BCO maintains all free slots as a continuous area by constructing each burst in the corner of the available bandwidth area in order to minimize external fragmentation (Lai and Chen, 2011). However, the subchannels with high channel quality are not always located in the corner of the area, and the construction of a burst in the corner would inevitably involve subchannels with poor channel quality, resulting in insufficient throughput.…”

“…Channel-aware Downlink Burst Allocation (CDBA), the subchannel-aware Burst Fragmentation Packing and Scheduling algorithm (BFPS), Best Channel Method (BCM), and the Best Corner-Oriented (BCO) algorithm in our earlier work were all proposed to take into account both the subchannel diversity and IEEE 802.16 DL burst specifications (Shih et al, 2010;Chen et al, 2011;Nusairat, 2012;Lai and Chen, 2011). CDBA constructs the burst in the continuous subchannels that all uses the same highest MCS (Shih et al, 2010).…”

Survey of Down Link Data Allocation Algorithms in IEEE 802.16 WiMAX

“…al. propose search for best corner algorithms (BCO) in [32]. The algorithm avoids request fragments, assign some extra slot and reduce the unused slot by placing the request in the best corner in the two-dimension subframe.…”