Smartphones and tablets are expected to contribute to a 12-fold increase in mobile data traffic between 2012 and 2018 as it grows at a compound annual growth rate of 50 percent.

According to Ericsson’s latest Mobility Report, the increase in smartphone sales saw mobile data traffic double between the third quarters of 2011 and 2012 with smartphone-based data traffic expected to exceed the average. During the third quarter 40 percent of phones sold were smartphones.

Much of the increase in data is expected to be taken up by video, which currently makes up 25 percent of total smartphone traffic and 40 percent of tablet data traffic.

Senior VP and head of strategy at Ericsson, Douglas Gilstrap, said the availability of smartphones and tablets have changed the way people use the internet and increased expectations around mobile network quality as a result.

Total mobile subscriptions reached 6.4 billion by the end of the third quarter with a global mobile penetration rate of 91 percent. Total mobile subscriptions are expected to hit 6.6 billion by the end of the year and reach 9.3 billion in 2018.

Global mobile subscriptions during the third quarter increased 9 percent year-on-year and by 2 percent on the prior quarter, with China accounting for around 40 million (35 percent) of all additional subscriptions during the period.

There were 13 million new LTE subscriptions in Q3 with technology with 55 million expected by the end of the year. LTE subscriptions are expected to hit 1.6 billion by 2018.

In terms of coverage, LTE was estimated to reach 455 million people by the middle of 2012 with more than half the world’s population expected to be able to access the technology within five years.

3G (WCDMA and HSPA) technology currently covers more than half the world’s population and continues to grow faster than LTE in absolute terms, adding 65 million subscriptions during the most measurement period.