Multi-stream aggregation (MSA): Key technology for future networks

In our recent 5G presentation here, we outlined multi-technology carrier aggregation as one of the technologies for the future networks. Some of the discussions that I had on this topic later on highlighted the following:

1. This is generally referred to as Multi-stream aggregation (MSA)
2. We will see this much sooner than 5G, probably from LTE-A Rel-13 onwards 

Huawei have a few documents on this topic. One such document is embedded below and aanother more technical document is available on slideshare here.

MSA: A key technology for the evolution of future wireless networks from Zahid Ghadialy