The U.S. mobile phone industry is running out of the airwaves necessary to provide voice, text and Internet services to its customers, according to CNNMoney.

The problem is known as spectrum crunch. It threatens to increase the number of dropped calls, slow down data speeds and raise customer rates.

The biggest driver is consumer demand for email, apps and video on mobile phones.

The iPhone, for instance, uses 24 times as much spectrum as an old-fashioned cell phone, and the iPad uses 122 times as much.

According to CNNMoney, AT&T's wireless data traffic on its network has grown 20,000 percent since the iPhone debuted in 2007.

When spectrum runs short and service degrades sharply, calls get dropped and data speeds slow down.

When the spectrum wall will be reached is debatable, but almost everyone in the industry agrees that a crunch is coming, maybe as early as next year.

The Federal Communications Commission has been working to free up more spectrum for wireless operators.