The Mobile World Congress (MWC) will kick off in Barcelona Sunday and the fans would finally have the list of the best 2012 wireless devices in hand.

They will get to see all versions of the devices from tablets to TVs, but this year, the star of the show is expected to be smartphones.

Here is a complete list of all the companies who plan to demonstrate their new technologies to fire up the smartphone market competition with their releases. Some are confirmed announcement while others are gleaned from rumors based on the companies' teasing statements.

Nokia: The popular handset manufacturer has officially stayed mum in the recent past. However, according to recent rumors, Nokia plans to reveal at least two Window phones in the trade show.

First, a mid-priced Windows Phone called Lumia 610 and the second, an international version of Lumia 900 Windows Phone -- a device that will be launched on AT&T's 4G LTE network next month in the U.S.

Nokia has also unveiled a teaser video that clearly has to do with a device sporting a high-end camera.

Assuming the specs, the new global version of Lumia 900 is going to stay the same sans LTE and the upgraded camera but one can expect a device sporting a 4.3″ AMOLED ClearBlack display, a single core 1GHz processor, a large 1830 mAh battery, 8 megapixel camera with a wide aperture sensor and Carl Zeiss optics and a 1.3MP front-facing camera with the same technology.

Microsoft: The company may unveil an operating system targeted at desktops and notebooks. Windows 8 is also rumored to foster considerably tighter integration with Windows Phone. Microsoft has gone big with its renaissance mobile platform in each of the last two Mobile World Congresses. In fact, Windows Phone 7 debuted there two years ago.

Meanwhile, Microsoft has been relatively tight-lipped but at least two major revisions are expected in 2012: Tango, which focuses on lower-end hardware for wider-scale internationalization, and Apollo, which is shaping up to be a more thorough revamp.

LG: LG is doing everything it can to steal the show. The company has released eight phones last week, including the Optimus 3D Max, Optimus Vu, three L-Style handsets, and Optimus 4X HD.  Optimus 4X HD should be the most promising of the pack with an Nvidia quad-core processor and Android 4.0 Ice Cream Sandwich.

Further, a stellar quad core-powered X3 will come out of cover at the MWC 2012. The company has not revealed anything about the device, which could be its first quad core-powered device.

It has been rumored that the device is expected to run on a quad-core Tegra 3 processor with a large 4.7-inch 720p display, Android 4.0 Ice Cream Sandwich, dual cameras with the rear one having an 8 megapixel sensor. To top it all, the LG phone is expected to pack in a powerful 2,000mAh battery.

HTC: HTC has already revealed three of the devices it intends to showcase at the event - the HTC One S, E and X.

All the three devices are expected to run on Android 4.0 Ice Cream Sandwich. They are likely to be released in the Q2 of 2012.

HTC One X will feature a 1.5GHz quad-core Tegra 3 processor and would be showing some impressive performance, compared to the present generation devices.

Samsung: It has been rumored that there are remote chances that Samsung will unveil the much-touted Galaxy S III at the WMC.

The company has already announced Galaxy S Blaze 4G, Galaxy S Ace 2 and Mini 2. Further, there are speculations about an upgraded version of Galaxy S2.

Sony: The company is expected to bring Xperia U and Xperia P Android phones. The P would have a 4-inch screen and a 1GHz, dual-core ST-Ericsson processor, and the U is rumored to be a more affordable phone with a 3.5-inch display and a 5-megapixel camera.

Further, recent reports speculate that Sony will launch a Window Phone device at the MWC.

Asus: Asus plans to spark the MWC with its long-awaited Padfone -- a device that was announced nearly nine months ago.

A phablet (a hybrid of phone and tablet) which runs on the Ice Cream Sandwich is likely to be unveiled at the show. But Ausus might go beyond that too. It has released a teaser video titled Twice the Detail, Twice the Fun, which naturally suggests that the company might roll out of a dedicated tablet with a high-res display.

Others: Further, there would be many more wireless telecommunication providers who are debuting and coming up with new devices to wow the consumers either with the best technologies or with aggressive price marketing.

ZTE, one of two companies trying to carve out a niche in the United States market for midrange Android phones, has already announced the Mimosa X, the first phone to ship with an Nvidia Icera modem as well as a Tegra 2 processor.

Huawei is expected to make some announcements. Acer has also announced the launch of its unique Liquid Glow handset targeted at the entry-level crowd. Motorola seems slated to have a very small presence at the show.

In short, the MWC 2012 promises to be the show that would offer the world the fastest, sleekest and the most powerful mobile devices.