s, there is a strong correlation between padding and allocation size. However, if 24 bytes of data could be transmitted without padding on three, four, or five slots, it would simplify the scheduling by allowing more flexibility in the resource allocation. This problem would have been more critical in the IEEE 802. .16m standard due to the use of rate matching and variable slot sizes, i.e., with fixed MCS, the burst sizes supported in different MIMO modes or over unequal subframe sizes would have been significantly different. The use of conventional MCS signaling and rate-matching together would have limited the set of FEC block sizes and MCS granularity. Therefore, the IEEE 802.16m standard adopted a different approach from the legacy standard for data burst modulation and coding that does not rely on MCS selection. CHAPTER 9 The IEEE 802. 16m Physical Layer (Part I) FEC Block Burst CRC Burst Randomizing Selection Encoder Collection Modulation Addition Partition Function Addition (CTC) Repitition FIGURE 9-45 Coding and modulation procedures for traffic channels [2] Figure 9-45 shows the IEEE 802.16m channel coding and modulation procedures. A cyclic redundancy check is appended to a burst (i.e., a physical layer data unit) prior to partitioning. The 16- bit CRC is calculated over the entire bits in the burst. If the burst size including burst CRC exceeds the maximum FEC block size, the burst is partitioned into KFB FEC blocks, each of which is encoded separately. If a burst is partitioned into more than one FEC block, a FEC block CRC is appended to each FEC block before FEC encoding. The CRC of an FEC block is calculated based on the entire bits in that block. Each partitioned FEC block, including 16-bit FEC block CRC, has the same length. The maximum FEC block size is 4800 bits. Concatenation rules are based on the number of information bits and do not depend on the structure of the resource allocation (number of logical resource units and their size). The IEEE 802. 16m utilizes convolutional turbo code with a 