Novatel Wireless claimed in a lawsuit filed on Thursday that ZTE and Franklin Wireless have infringed five of the patents behind its popular MiFi mobile hotspot devices.

The MiFi Intelligent Mobile Hotspot devices connect to the Internet via a cellular data radio and can share that Internet connection with several other devices via Wi-Fi.

This lets cellular subscribers enjoy their mobile data accounts on multiple platforms and gives laptops and other devices Internet access outside Wi-Fi coverage areas. MiFi products are sold by 25 carriers around the world, including AT&T and Verizon Wireless in the US and 3 in the UK.

Novatel says it invented the product category and holds many US and international patents on the technology. But there are also portable hotspots made by China-based ZTE, including Verizon's FiveSpot. Novatel is suing both ZTE and its US subsidiary, ZTE USA, as well as Franklin, a maker of wireless access devices.

In its complaint, Novatel claims both Franklin and ZTE infringed US Patent No. 5,129,098, entitled "Radio Telephone Using Received Signal Strength in Controlling Transmission Power," as well as Patent No. 7,318,225, for a software-reconfigurable modem, and Patent No. 7,574,737, "Systems and Methods for Secure Communication over a Wireless Network."

Novatel also claims that Franklin violated Patent No. 7,319,715, "System and Methods for a Multi-Mode Wireless Modem," and that ZTE infringed on Patent No. 6,785,556, covering a software-configurable wireless modem with multiple operating modes.

The company is seeking compensatory damages, plus enhanced damages of three times that amount for "willful infringement," and court costs. Novatel is also asking the court to block ZTE and Franklin from continuing to infringe the patents.

Neither ZTE nor Franklin could immediately be reached for comment.