Total mobile smartphone and tablet subscriptions in North America reached 330 million in the first quarter of 2012, or about one-third the number in either China or India, Ericsson said in a 28-page report released Tuesday.

In all, about 6.2 billion mobile phones and tablets used by some 4.2 billion subscribers were connected over wireless networks globally in the quarter, Ericsson said.

By 2017, the total of mobile subscriptions is projected to reach 8.9 billion worldwide, a number that doesn't include a vast number of machine-to-machine connections.

In North America, the 330 million mobile subscriptions should grow to nearly 500 million by 2017, Ericsson said.

Some 1 billion of the current worldwide mobile subscriptions are for smartphones. Ericsson projects that number will grow to about 3.1 billion of the total in 2017.

Ericsson, which manufacturers a broad portfolio of wireless switching gear, also said 4G LTE networks with download speeds of greater than 10 Mbps grew the fastest over the past year in North America.

Ericsson didn't estimate the number of North American LTE subscribers who are served by major U.S. carriers.

LTE networks remain only a tiny fraction of all wireless networks.

GSM 3G is still the largest wireless network globally, with nearly 5 billion mobile subscriptions.

In 2017, Ericsson says there will be approximately 1 billion LTE subscriptions worldwide, and 3 billion over GSM and 3 billion over Wideband CDMA/HSPA.

Matt Hamblen covers mobile and wireless, smartphones and other handhelds, and wireless networking for Computerworld. Follow Matt on Twitter at @matthamblen, send e-mail to [email protected] or subscribe to Matt's RSS feed .

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