Some of those issues could be resolved as chip circuitry gets smaller and LTE modems are integrated in processors over the coming years, McGregor said.

Qualcomm's latest Snapdragon chips integrate 3G/4G inside the chip, and the company has said its quad-core chips will be used in LTE phones in the future. Nvidia's Icera 410 LTE modem isn't integrated, and a company spokesman said the part is best suited for tablets and clamshell devices. Nvidia's integrated Tegra processor with a CPU and modem is coming in 2013, and that chip will go into devices such as tablets and smartphones.

Smartphone chip supplier Texas Instruments has because of cost and heat concerns.