South Korean mobile phone maker LG Electronics was already known to plan the release of a series of handsets running under Microsoft's Windows Phone 7 operating system, and one of these devices has just received FCC approval, the LG E900.

Interestingly enough, it seems that the phone passed through the Federal Communications Commission with GSM 850 and 1900 radio frequencies on board, suggesting that it would be released on the market on AT&T's airwaves, Engadget notes in a recent post.

In a way, this should not come as a surprise, since AT&T did announce previously that it should be premier carrier for Windows Phone 7.

However, two other LG handsets based on Microsoft's new OS were spotted at FCC lately with support for the carrier's network, and that might not sound too promising for other carriers in the country.

However, it might not be too long before LG Windows Phone 7 devices with support for other networks make it into the wild too, for there are little chances that AT&T would be the exclusive carrier for Windows Phone 7.

Until more on this emerges, we should note that the LG E900 is expected to land on the market with Bluetooth and Wi-Fi 802.11 b/g/n 2.4GHz connectivity on board, as well as with a 1GHz Snapdragon processor inside.

We've already spotted the device into the wild in leaked photos and videos, when it was rumored to land on the market as the LG Optimus 7.

In addition to E900, FCC has just approved another LG device, this time an Android-based one, the LG E720, which packs only support for EDGE connectivity.

There are no other details on the handset's arrival on the United States market, and there are great chances that it won't make it there, especially since no 3G support is mentioned in the FCC filing.