Clearwire said Thursday it has signed a wholesale agreement with New Jersey-based Locus Telecommunications to provide prepaid 4G mobile broadband service.

The service will be available in Chicago later this year, although the companies did not disclose details on specific timing and pricing. Locus said it currently offers wireless service and calling cards in more than 70,000 locations around the country and has more than 300,000 subscribers for its prepaid wireless service.

Competition between 4G providers has been heating up as companies jostle for customers and the revenues that come from data-intensive activities such as streaming movies and gaming. Clearwire was the first operator to launch in Chicago, although its product portfolio does not include mobile phones. It was not clear from Clearwire and Locus’ announcement what kind of products will be available for the prepaid 4G service.

Locus said its prepaid 4G service will offer average mobile download speeds of 3 to 6 megabits per second. Typical 3G speeds clock in between 800 kilobits to 1.2 megabits per second.