Mostly common deployment of LTE in North American market is FDD based. There have been some operators who made move in TDD deployment.
Previously I discussed LTE throughput that can be achieved in Downlink for LTE FDD case
Today, we will talk about How much throughput you can achieve (in theory) for LTE Downlink TDD scenario.
However, for TDD case, the computation is not as simple as it may sound. This is because of different UL and DL sub-frame configurations and special subframe configurations in TDD Radio
Frame. If you don’t know what I am talking about. Watch the video of TDD Radio frame once again : )
Depending upon the TDD configurations you consider. TDD radio frame can have different throughput analysis.
For this detail below. The analysis is chosen for subframe configuration 0 because it has the least number of downlink subframes.
For this detail below. The analysis is chosen for subframe configuration 5 because it has the most number of downlink subframes.
For this analysis, special subframe configuration 0 is selected because it has the least number of OFDM symbols within the DwPTS field of the special subframe
For this analysis, special subframe configuration 4 is selected because it has the most number of OFDM symbols within the DwPTS field of the special subframe
The table below presents the maximum throughput (in theory) which can be achieved if all Resource Elements are allocated to the data channel i.e., Physical Downlink Shared Channel (PDSCH)
and there are no overheads added. Please remember that these values are not achievable in practical scenarios. However, it gives you an idea to compare realistic throughputs with this maximum expected theoretical throughput.
expected theoretical throughput.
Theoretical Throughput in LTE TDD if all Resource Elements are allocated to the PDSCH ( Credits: LTE in Bullets )
Few observations from the table above.
In case of both TDD and FDD, Physical Downlink Shared Channel (PDSCH) is used to transfer application data and throughput.
The throughput achievable depends upon :