This will mean that mobile data traffic will grow by eight times.
The Swedish company said it expected there will be 6.8 billion smartphone subscriptions globally by the end of 2022, up from 3.9 billion in 2016.
In its previous forecast from June this year, Ericsson had said it expected 6.3 billion smartphone subscriptions by the end of 2021.
Ulf Ewaldsson, head of strategy and technology at Ericsson, said the biggest change from its previous report was the jump in 5G subscribers to 550 million in 2022 from 150 million in 2021.
He claimed that a quarter of the new subscribers will be in North America and 10 percent in Asia.
The first 5G networks will be launched at the end of 2017 and Ericsson plans to sell 5G equipment on a “larger scale” in 2018, Ewaldsson said.
Ericsson said mobile data traffic continues to grow, driven by an increase in smartphone subscriptions and data volume per subscription, fuelled primarily by more viewing of video content.