Orange and Ericsson have successfully used the 3.4-3.6 GHz (3.5 GHz) frequencies for testing data speeds, coverage and FDD carrier aggregation. This live LTE-Advanced FDD trial, which was authorized by the French regulator ARCEP, was carried out in October-November 2014 on Orange's network in Bordeaux, France, using Ericsson's pre-commercial equipment.

The first phase of the trial was performed at the Orange Labs in Paris. In this trial, speeds of 300 Mbps were achieved by using the 3.5 GHz band in aggregation with the 2.6 GHz band, thereby confirming the potential of 3.5 GHz FDD technology to increase mobile broadband capacity. The second phase was carried out on Orange's live mobile network and was based on Ericsson's pre-commercial FDD 3.5 GHz radio base station equipment.

For the trial, new antennas supporting the 3.5 GHz band were installed at the Le Ponant and Meriadeck sites in the center of Bordeaux. A range of streaming-based services were tested allowing the team to continuously monitor network performance between the base station and the mobile prototype throughout the live trial. The data throughputs acquired during the tests were measured, both before and after carrier aggregation of the two bands. A peak performance of 150 Mbps at a distance of up to 700 m was achieved in the 3.5 GHz band when used alone, and speeds of 300 Mbps was attained when used in aggregation with the 2.6 GHz band.

"This live FDD trial demonstrated that the 3.5 GHz band can be successfully used in urban and suburban environments in stand-alone mode or in aggregation with another band to provide advanced mobile broadband services using a FDD access scheme for high peak data rate applications to enhance user experience," said Alain Maloberti, Senior Vice President, Orange Labs Networks.

This project has provided an opportunity to gather essential experience on the ways future multi-frequency networks could be optimized from cost and performance perspectives. One of the most rewarding results of the trial is the confirmation that the existing network grid can be reused for a 3.5 GHz macro grid; in Bordeaux, the trials used the same grid as for the 1800 MHz and 2.6 GHz bands.

"This live FDD trial also demonstrated that the macro coverage of 3.5 GHz spectrum is suitable for providing substantial capacity gains that can satisfy future consumer needs," said Thomas Noren, Vice President, Head of Radio Product Management, Ericsson.

The successful trial's results re-confirm that the FDD access scheme is a promising solution for the 3.5 GHz band to provide mobile operators additional capacity for advanced services and applications in Europe.