Qualcomm announced its third-generation 5G Modem-RF System today, and as you'd expect from any third generation of a new technology, the Snapdragon X60 continues to move it forward in a meaningful way. One of the big new features is mmWave-sub6 aggregation, and Qualcomm says that the feature allows for maximum throughput of 5.5Gbps.
5G is a combination of mmWave - which are high-frequency bands that are super-fast, but can be obstructed by the tiniest thing, like a drop of water, a window, or a piece of paper - and sub6, lower-frequency bands that can penetrate buildings, but aren't as fast. Moreover, your smartphone isn't as powerful as a cell tower, so while the tower might be able to send you that speedy mmWave signal, your phone can't send one back, and it will need to send a sub6 signal.
Aggregation of these two segments of 5G should allow them to work more seamlessly together, and it's going to be an important piece of the 5G puzzle. It's similar to how important carrier aggregation was to 4G LTE, and in fact, the Snapdragon X60 is adding sub6 carrier aggregation as well. That means that we can also see double the sub6 speeds that we saw in the Snapdragon X55.
Along with being built on a 5nm process - while the Snapdragon X55 was 7nm - Qualcomm introduced the smaller QTM535 mmWave antenna module. This is also important to the evolution of 5G, because a smaller antenna means that it can fit into thinner and sleeker form factors.
The big focus with the Snapdragon X60 is continued development of 5G, helping carriers move from non-standalone to standalone 5G. Like the X55, it uses Dynamic Spectrum Sharing to make use of both 4G LTE and 5G, but eventually, the world is going to move to the latter.