Story highlights The volume of illegal robocalls is increasing in the U.S.

Federal Trade Commission held a Robocall Summit to address problem

The FTC is offering $50,000 prize for the best idea for blocking robocalls

During election season, phones across the country ring with more unsolicited, automated calls than usual. So it's especially timely that on Thursday the U.S. Federal Trade Commission held a Robocall Summit to "explore innovations designed to trace robocalls, prevent wrongdoers from faking caller ID data, and stop unwanted calls."

A "robocall" is an automated phone call that plays a prerecorded message. If you hear a live person and it's a telemarketing, advocacy, or survey call, it could still be illegal if it's unsolicited, but it's not a robocall. Robocalls from political campaigns or get-out-the-vote efforts are allowed (and legal) under the FTC's Telemarketing Sales Rule , as well as under most state robocall laws (except when made to cell phone numbers and a few other exceptions).

Unsolicited commercial telemarketing calls are illegal, and rampant, in the U.S. According to new FTC statistics , this problem is getting worse, fast. In the last year, the number of consumer complaints about unwanted telemarketing calls soared 70% to an all-time record of 3,840,572 during fiscal year 2012.

Fed up with the phone spam, over 217 million Americans have already added themselves to the National Do-Not-Call Registry . But this only solves part of the problem.

Much phone spam comes from companies, groups and scammers that choose to ignore the law. Also, a large proportion of consumer phone spam complaints cannot be investigated because of evasion measures such as "spoofing" -- or hiding -- the originating phone number or caller ID information.

To address the robocall problem, the FTC announced a contest at the Summit to find technological ways to curb illegal robocalls. The FTC Robocall Challenge challenges the public to suggest plans to block illegal robocalls on landlines and mobile phones. Ideas must include a technical proposal -- so options to, say, prevent caller ID spoofing would qualify, but nontechnical suggestions such as "give phone spammers the death penalty" are not eligible.

The winning solution will receive a $50,000 cash prize, as well as opportunities for promotion, exposure, and recognition by the FTC. Entrants retain ownership of their proposed solutions.

If you're interested in entering, the deadline for entries is January 17, 2013. The winner will be announced April 1, 2013. (Hopefully people won't think it's an April Fool's Day joke.)

For now, here's what to do if you get an unsolicited commercial phone call -- whether a robocall or from a live person:

1. Hang Up. Do not press 1 or any other numbers to get off the list.

2. Consider blocking the number.

3. File a complaint with DoNotCall.gov . It helps, but isn't necessary, to have the number from which the call was initiated.

Remember that political and get-out-the-vote robocalls are legal, so there's no point in filing complaints about these with DoNotCall.gov. However if these calls really annoy you, then you might consider complaining about them to your government representatives.

The opinions expressed in this post are solely those of Amy Gahran.