 Cell-Specific Antenna Ports Ports Region frame Regular 18 (10.7%) 24 (14.3%) 32 (19.0%) 18 (10.7%) 24 (14.3%) 32 (19.0%) 30 (17.9%) 36 (21.4%) 40 (23.9%) 30 (17.9%) 36 (21.4%) 40 (23.9%) frames 42 (25%) 48 (28.6%) 52 (31.0%) 42 (25%) 48 (28.6%) 52 (31.0%) MBSFN 12 (7.1%) 12 (7.1%) 12 (7.1%) 12 (7.1%) 12 (7.1%) 12 (7.1%) 24 (14.2%) 24 (14.2%) 24 (14.2%) 24 (14.2%) 24 (14.2%) 24 (14.2%) frames 36 (21.4%) 36 (21.4%) 36 (21.4%) 36 (21.4%) 36 (21.4%) 36 (21.4%) antenna-ports, and is 12 resource elements (7.1%) for one and two antenna ports, and 24 resource elements (14.3%) for three to eight antenna ports. Note that the overhead due to UE-specific reference signals is only present in resource blocks in which UE-specific reference signals are transmitted. The relative overhead due to synchronization signals and physical broadcast channel depends on the operation bandwidth. A total of 528 resource elements per 10 ms radio frame are used for the synchronization signals and physical broadcast channel for four CRS ports, corresponding to approximately 0.6% and 0.3% overhead for 10 and 20 MHz operation bandwidth, respectively. The overhead due to PDU headers is proportional to data packet size and is approximately 2.7%, 0.51%, and 0.32% for physical-layer data rates of 1, 10, and 100 Mbits/s, respectively. This overhead is not included in the self-evaluation results. The relative overhead due to CSI-RS depends on the number of antennas and the periodicity. In a typical case, it is about 0.12% per antenna port (0.48% for four antenna ports and 0.96% for eight antenna ports). The relative overhead due to UE-specific RS is estimated at approximately 7% in the case of rank 1 and rank 2 transmission, and 14% for rank 3 to 8 transmission. In the uplink, the L1/L2 overhead includes the Demodulation Reference Symbols (DM-RS) that are used in uplink channel estimation for coherent demodulation and that are transmitted once every 0.5 ms. It further includes the Sounding Reference Signal (SRS) used for uplink channel state esti- mati