Good news for vendors of wireless broadband equipment: mobile operators are ratcheting up their capex spending this year, although some experts disagree by how much and where.

Over at ABI Research, analysts said on Monday wireless carriers will invest 4 percent more, year-over-year, in infrastructure in 2010. And providers in South America will lead the pack with a compound annual growth rate of 10 percent between 2009 and 2015, ABI said.

The GSM Association, however, said last month Asia Pacific will be top capex dog as it forks out $34 billion of the predicted $72 billion worldwide on mobile broadband technologies this year. The organization said operators in North America will funnel $19 billion into their networks and their peers in Europe will reach up to $14 billion in similar outlays.

Either way, the outcome is positive for the communications industry. ABI said wireless capex growth will outpace the 2.7 percent contraction that took place globally in 2009. That’s because, despite the lingering economic recession, more consumers are using data-greedy smartphones. So, wireless carriers are investing in 3.5G technologies such as HSPA and HSPA+, as well as 4G LTE networks.

Along those lines, AT&T Inc. (T) alone will boost its wireless backhaul outlay by between 100 and 200 percent, analysts at investment bank UBS said on Monday. Thanks to iPhone use, AT&T will continue shifting from traditional T1/T3 TDM backhaul to optical/Ethernet infrastructure, analysts wrote in a client memo.

Meantime, AT&T’s rivals, in the United States and overseas, will mirror that activity. For example, Verizon Wireless (VZ) is ahead of AT&T in preparing to launch its LTE network, and, as ABI pointed out, so is Sweden’s TeliaSonera.

The capex turnaround from last year comes in part because operators made more on mobile Internet access than perhaps they expected. Developed markets such as North America and Western Europe saw a more than 17 percent year-over-year rise in mobile Internet revenue in 2009, ABI found. The trend promises to continue throughout this year as well, the firm said.