Now that AT&T's purchase of Time Warner finally has passed government muster, T-Mobile US and Sprint will run their own proposed merger before the regulatory gauntlet next week as they go before a U.S. Senate antitrust panel.

T-Mobile and Sprint, analysts say, aim to win merger approval by convincing regulators that they'll increase competition by selling 5G residential broadband services. Their 5G wireless services would compete with phone companies' broadband in rural areas. It would also compete with cable TV companies in urban and suburban settings.  

In their regulatory filing, the companies noted that "as a combined company, the carrier will have the luxury of deploying all of Sprint's 2.5 (gigahertz) spectrum for 5G. If Sprint were a stand-alone, the carrier would need some of its 2.5 (gigahertz) for (4G) wireless," Cowen & Co. analyst Colby Synesael said in a report to clients.  

T-Mobile and Sprint, in a regulatory filing on Tuesday, said they need to merge to create a stronger competitor to Verizon Communications and AT&T. AT&T closed its purchase of Time Warner last week as it won an antitrust case vs. the Department of Justice.