Google (NASDAQ: GOOG) acquired Alpental Technologies, a Seattle-area startup that was headed by engineers from the former Clearwire and is working on 5G-related millimeter-wave technology.

Google confirmed to multiple news outlets that it acquired Alpental a few weeks ago but provided no additional information.

The startup was founded by Pete Gelbman, who spent seven years with Clearwire and was part of its CTO group, and Mike Hart, formerly a principal systems architect at Clearwire and member of the CTO's research and development team. WiMAX and TD-LTE pioneer Clearwire was acquired by Sprint (NYSE: S), which is continuing to roll out TD-LTE on Clearwire's 2.5 GHz spectrum.

Not a lot of specifics are known about what Alpentel has been working on. Gelbman's LinkedIn profile states that Alpental was "developing a new self-organizing, ultra low power Gigabit wireless technology to extend fiber optics." That has led some observers to suggest Google's interest in Alpental involves the expanding Google Fiber service that is being rolled out in cities across the United States. (In other news, Google is also reportedly pondering an investment in a new subsea cable across the Pacific Ocean, according to The Wall Street Journal.)

Hart, who was Alpental's CTO, said in his LinkedIn profile that he has been working on millimeter-wave systems, specifically, WiGig/802.11ad, "utilizing CMOS analog phased arrays and design of multi-gigabit baseband." That description complements a letter the startup sent to the FCC last year, which was cited by WSJ's Digits blog, in which Hart stated Alpental's technology makes use of the 60 GHz spectrum band.

Gelbman noted that Alpental's technology would enable a scalable, millimeter-wave networking solution for dense, urban next-generation 5G and Wi-Fi networks at the form factor and cost of an Apple (NASDAQ: AAPL) iPod.

Geekwire last summer uncovered a Securities and Exchange Commission filing in which the startup said it had attracted funding of $850,000. Craig Barratt, former CEO of Wi-Fi chip pioneer Atheros Communications, which is now part of Qualcomm (NASDAQ:QCOM), is said to have spearheaded the Alpental acquisition on behalf of Google, where he is now a senior vice president.

Google has been on an acquisition roll, making at least five purchases last month and at least three so far in June, according to Bloomberg. Along with confirming its acquisition of Alpental, Google also said it had bought multi-screen ad firm MDialog.

The most high-profile deal so far this year is Google's acquisition of Nest Labs, which makes smart digital thermostats and smoke alarms, for $3.2 billion. Nest Labs, in turn, just agreed to spend $555 million acquiring Dropcam, which makes in-home cameras that can be checked via smartphone.

Meanwhile, Google has continued expanding the reach of its Project Loon balloon-based Internet initiative. The company launched a Loon balloon in the rural outskirts of Campo Maior, Brazil, connecting Linoca Gayoso, a local school, to the Internet for the first time.

Source: Project Loon

Google noted that this was the first time it had tested LTE technology with its balloons, opening the door to enabling the company to provide an Internet signal directly to mobile phones. Project Loon is also conducting tests using LTE spectrum in the Nevada desert.

Google's balloons have had some troubles in recent weeks. During May 2014, a plummeting balloon struck a power line over Washington state, and another balloon landed in the sea of the coast of New Zealand and was mistaken for a crashing airplane.

For more:

- see this Google blog entry

- see this WSJ article and this article (sub. req.)

- see this Geekwire article

- see this Bloomberg article and this article

- see this Google+ post

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