You probably know that LTE is divided in categories, shorthand "Cat" which you can see everywhere in Techship's available documentation and website. But is higher always faster? And is a Cat-4 always a Cat-4?
The answer surprisingly is no. Let's take an example with LTE Cat-12 which has been around for quite a while, it boasts 600Mbps DL and 150Mbps UL capabilities. So does that mean an LTE Cat-13 module is even faster? No, an LTE Cat-13 provides 400Mbps DL and 150Mbps UL. Meaning that the uplink performance is the same, but the downlink performance is different between these two categories. This generally stems from a separation of DL/UL performance in the 3GPP standards, meaning that modules from 3GPP standard before 12 conforms to a combined UE category system, and after 12 it separates the DL/UL categories. This means that what is typically defined as an LTE Cat-7 device (300Mbps DL/150Mbps UL) is actually LTE Cat-7 UE DL and LTE Cat-13 UE UL.
And our mystical comment about LTE Cat-4? Well not all Cat-4's are the same either. LTE Cat-4 was introduced in 3GPP Release-8 with 150Mbps DL and 50Mbps UL using 64QAM. In a later release, support for 256QAM DL was introduced, meaning that newer chipsets supporting LTE Cat-4 can utilize this high downlink modulation scheme. An example being a lot of today's 5G RedCap modules supporting LTE Cat-4 based on 3GPP Release-16.
If you want to know more about 3GPP releases, you can contact our experts, or dig through the archives at 3GPP.