![]() ![]() The peak data rate is then 0.75 x 50.4 Mbps = 37.8 Mbps. The total approximate overhead for the 5 MHz channel is 17.86% + 4.76% + 2.6% = 25.22%. ![]() The other channels (PSS, SSS, PBCH, PCFICH, PHICH) added together amount to ~2.6% of overhead.Downlink RS signal uses 4 symbols in every third subcarrier resulting in 16/336 = 4.76% overhead for 2×2 MIMO configuration. ![]() Assuming that on average it is 2.5 symbols, the amount of overhead due to PDCCH becomes 2.5/14 = 17.86 %. PDCCH channel can take 1 to 3 symbols out of 14 in a subframe.We now have to subtract the overhead related to control signaling such as PDCCH and PBCH channels, reference & synchronization signals, and coding. The MIMO data rate is then 2 x 25.2 = 50.4 Mbps. Then we calculate the data rate assuming 64 QAM with no coding (64QAM is the highest modulation for downlink LTE):Ħ bits per 64QAM symbol x 4,200 Res / 1 msec = 25.2 Mbps We first calculate the number of resource elements (RE) in a subframe (a subframe is 1 msec):ġ2 Subcarriers x 7 OFDMA Symbols x 25 Resource Blocks x 2 slots = 4,200 REs ![]()
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