The very main focus of LTE is to offer higher throughput. In LTE the throughput increases when we add more carriers(carrier aggregation). If we use higher modulation technique then the throughput increases by almost 30% further and when we increase the number of transmit and receive antennas the throughput gets doubled. This is all possible only under ideal conditions. Lets have a look at the throughput for different combinations of CA, MIMO and modulation techniques in downlink.

First lets have a look at the theoretical throughput values for every addition of component carrier (CC) in case of a 2x2 MIMO. The throughput doubles with the addition of each 20MHz carrier.

LTE Throughput Information

 

At present 64QAM is commonly used by all network operators and slowly they will be activating 256QAM in their networks. Now lets have a look at the theoretical throughput values for every addition of component carrier (CC) in case of a 2x2 MIMO with 64QAM and 256QAM in downlink. With the use of 256QAM the overall throughput increases by 33% in downlink.

Most of the smartphones that are available in the market supports 2x2 MIMO in LTE. Some devices do have the hardware to support 4x4 MIMO but the network does not support it at present (except in a very few countries). There are also plans for the network operators to support 4x4 MIMO but that would take some more time as the testing are in progress. Now lets have a look at the theoretical throughput values for every addition of component carrier (CC) in case of a 2x2 MIMO and 4x4 MIMO with 64QAM in downlink. With the use of 4x4 MIMO the throughput doubles when compared to the 2x2 MIMO.

 

Finally lets compare the theoretical throughput values for every addition of component carrier (CC) in case of a 4x4 MIMO with 64QAM and 256QAM in downlink.

There is also carrier aggregation in uplink but is only up to 2CA. Lets have a look at the theoretical throughput values for single band LTE and 2CA with the use of 16QAM and 64QAM modulation techniques in uplink.

 

Below is a table that represents the percentage increase in throughput values with the use of Carrier Aggregation, MIMO, modulation techniques in downlink and uplink.

NOTE: X and Y could be any LTE band.