Source: Flickr/Carl Lender.

One company could be participating as both a buyer and a seller in the FCC's upcoming incentive auction. During Comcast's (CMCSA -1.92%) fourth-quarter earnings call earlier this month, CFO Mike Cavanaugh told analysts, "We will be filing to participate in the upcoming forward spectrum auction."

Later this year, the FCC will hold an auction for spectrum in the 600 MHz range, which is currently owned by television broadcasters such as Comcast's NBCUniversal. The auction will have two parts: a "reverse" auction where broadcasters give up their spectrum licenses, and a "forward" auction where companies bid on it. Comcast will possibly bid against wireless carriers such as Verizon (VZ -1.10%), AT&T (T -0.67%), and T-Mobile (TMUS -0.40%). Back in October Comcast management said its NBCUniversal subsidiary will likely participate in the "reverse" portion of the auction.

What does this mean for carriers?
Comcast's decision to "take a paddle" in the spectrum auction doesn't mean it's going to play a significant role in the auction similar to how DISH Network bid up prices in last year's AWS-3 auction. CEO Brian Roberts notes that the auction may provide an opportunity for Comcast to acquire a strategic asset at a low price, so it's taking the opportunity to join the auction. It doesn't cost anything just to participate.

That's good news for wireless carriers, especially T-Mobile, which will benefit from a reserve of spectrum licenses for smaller carriers. Comcast technically qualifies to bid on the reserve as well, but with Comcast likely looking to score a bargain, T-Mobile should be able to acquire whatever spectrum it needs from the reserves. T-Mobile CFO Braxton Carter said the Un-Carrier could spend as much as $10 billion in the upcoming auction, but believes he'll be able to secure everything it needs for closer to $1 billion.

Surely there won't be any bargains outside of the reserve, as AT&T and Verizon are both hungry for spectrum licenses as their network capacity becomes crowded. While AT&T is losing phone connections, it's adding millions of Internet of Things connections every year. Verizon continues to add smartphone and tablet subscribers, and must expand its network bandwidth in order to maintain its lead in service quality and demand premium pricing. 

Note that the spectrum licenses up for auction this year likely won't be able to be used for another 39 months after the auction is completed. So, this requires some very long-term planning.

But what does Comcast want with wireless spectrum
Comcast has a lot of assets in hand already that could enable it to launch a regional wireless service provider. It already has millions of Wi-Fi hot spots throughout its footprint as a cable provider. Additionally, it activated a mobile virtual network operator agreement with Verizon in October, allowing it to tap Verizon's network to provide some form of wireless service. It's also been in talks with other carriers about a hybrid Wi-Fi-cellular phone service.

Adding some strategic spectrum licenses could lower the long-term costs of the service while improving the quality, but, as mentioned, the price has to be right for Comcast to actually buy any licenses.

With AT&T's acquisition of DirecTV, it suddenly became Comcast's biggest competitor in pay-TV service. AT&T is able to bundle wireless service with its new satellite TV offering, which is able to compete in the same footprint as Comcast.

In order to fight back, Comcast appears to be looking into a wireless service of its own, so it can offer the so-called "quadruple-play bundle" -- television, Internet, home phone, and wireless. If Comcast can use its Wi-Fi hot spots to cut down on costs, it should be able to undercut AT&T's wireless pricing and maintain its foothold with video and Internet subscribers.

While Comcast will be eligible to participate in the incentive auction, it would be a surprise if it walked away with licenses that cost much more than the FCC's reserve price. It already has enough assets to launch a wireless service to remain competitive with AT&T. Other wireless carriers don't have much to worry about.