The University of Minnesota filed federal patent infringement lawsuits against the nation’s four largest wireless service providers on Wednesday.

The institution alleges that Verizon Wireless, AT&T, Sprint and T-Mobile are illegally using technology developed in part by a University researcher to make their wireless communication services faster and more reliable.

All four companies declined to comment on the suits.

The researcher mentioned in the suits, Georgios Giannakis, is a University professor and the director of the University’s Digital Technology Center. He declined to comment through a spokesman because he will be a witness in the cases.

The quality of the technology and the fact that it makes the companies a lot of money were key reasons for the lawsuits, said University General Counsel William Donohue.

“Our faculty have developed an important piece of technology, which the University has [patented],” he said. “We think it’s important for us to protect that and to make sure that people pay a reasonable royalty if, in fact, they want to use important technology like this from the University.”

The University made almost $40 million in royalty revenues from licensing and commercializing its various inventions last year, according to the suits.

The University’s complaints, filed in Minnesota’s U.S. District Court, mention no specific dollar amount but ask for royalties and damages from the companies.

Donohue said the University doesn’t often engage in lawsuits like these, adding that he’s only dealt with a few in more than 15 years with the institution.

The University has enlisted Boston-based Fish and Richardson, a top national law firm specializing in patent and technology law, to help the school’s legal team argue the case. The historic firm counts Thomas Edison, the Wright brothers and the inventor of the telephone among its past clients.

Because the phone companies are so large, Donohue said, he expects these lawsuits to go on for a long time, though the companies could settle. He expects the companies to submit answers to the complaint in the next several weeks.