The last few years have proven a tremendous opportunity for wireless investors. Picking out solid yet oversold companies was almost too easy. The wireless sector was one of the first to snap out of the market funk late in 2002, with a broad base of leaders quickly outpacing the laggards. Just take a look at where some wireless bellwethers and nifty mid caps stand today:

  • Nextel Communications (NASDAQ:NXTL): up 300% in 2 years
  • Garmin (NASDAQ:GRMN): up nearly 200% in 2 years
  • Nortel Networks (NYSE:NT): up over 200% in a year
  • Research In Motion (NASDAQ:RIMM): up nearly 600% in a year

Another company in the 600% club is Sierra Wireless (NASDAQ:SWIR). Stock in the little known Canadian manufacturer of wireless cards for laptops has been on a tear lately, growing revenues and recently reporting a profitable fourth quarter and full year. While expanding sales in North America, it's also recently made inroads in Europe, China, and other international markets.

The company recently acquired its prime rival -- private CDMA player Airprime -- that brings with it key customers such as Sprint PCS (NYSE:PCS) and Audiovox. The deal made a lot of sense: Airprime focused exclusively on CDMA wireless data devices, while Sierra Wireless' product line favored other data technologies such as GPRS. While Sierra Wireless already had CDMA products, the acquisition brought them coveted experience in Qualcomm's (NASDAQ:QCOM) CDMA broadband data technology called EV-DO, which Verizon Wireless is now rolling out nationwide.

Sierra Wireless is also branching out into the smartphone market and is poised to offer its first product -- the Voq professional phone -- by midyear. The combination cellular phone and PDA uses Microsoft's Windows Mobile operating system and is aimed at mobile professionals around the globe.

Risks certainly lie ahead, however. Many of the recent wireless high-fliers are now richly valued (some even overblown), and Sierra Wireless is not as cheap now at five times sales. Developing smartphones is very capital intensive, so a lot rides on the success of its Voq line.

A recent secondary offering brought the company $75 million to help fund the launch of Voq and other new products, but investors are banking on a beefed-up bottom line to fund future growth. With the wireless data market finally taking off though, Sierra Wireless is well-positioned to capture a good share of a growing market.

Dave Mock is co-author of Tapping into Wireless and owns shares of Nextel.