Huawei, Vodafone Romania mix it up with FDD + TDD, 5 carrier aggregation

Huawei (Flickr)
Image: Kārlis Dambrāns/CC BY-SA 4.0

Forget three-carrier or even four-carrier aggregation. Huawei and Vodafone Romania are now talking five-carrier aggregation (5 CA) as part of a demonstration in which they achieved a 1.35 Gbps LTE connection using an end-to-end solution from Huawei.

All the major carriers in the U.S. last year revealed how they're in the process of rolling out 3 CA in various markets, and the next step is 4 CA as part of the standards related to LTE-Advanced. A spokesperson for Huawei was not immediately available for comment, but a press release states the test in Romania also involved a combination of 4x4 MIMO, “innovative mix of FDD + TDD” over 5 CA and higher order modulation – 256 QAM.

Vodafone Romania, the country’s second largest cellular phone company by subscribers, launched its Supernet 4G+ dual-carrier LTE-A services across more than 350 cities back in September, TeleGeography reported at the time. By aggregating the 800 MHz and 1800 MHz radio frequencies to increase available 4G bandwidth, Vodafone promised higher data download speeds for compatible smartphones, improved mobile HD video streaming and better 4G indoor coverage.

Carrier aggregation is a major feature of LTE-A and allows mobile network operators to combine a number of separate LTE carriers, increasing the peak user data rates and overall capacity. It also allows them to take advantage of fragmented spectrum allocations. 

RELATED: AT&T: We are deploying 3-channel carrier aggregation on LTE network

Ovum analyst Daryl Schoolar said 5 CA is just part of the LTE-A evolution, but the fact they used FDD + TDD in the test is interesting. In the U.S., most operators’ LTE networks are based on FDD-LTE (Frequency Division Duplex) rather than TDD-LTE (Time Division Duplex), which is what Sprint uses as well as operators like China Mobile.

In 2013, Samsung Electronics announced the first commercial devices capable of TDD-LTE and FDD-LTE seamless handover, launching TDD/FDD dual-mode LTE versions in the Samsung Galaxy S4 and Samsung Galaxy S4 mini, allowing for seamless voice and data communication as devices switch between the two different types of LTE networks. The company said at the time that it expected to see increased adoption of TDD-LTE in the U.S., China, Australia, the Middle East, Northern and Eastern Europe and Southwest Asia.

RELATED: Sprint’s iPhone 7 could go up to 200 Mbps in some markets due to 3-channel carrier aggregation

Last fall, Sprint confirmed to FierceWireless that Apple's iPhone 7 supports 2- and 3-channel carrier aggregation on Sprint’s 2.5 GHz spectrum band. Sprint’s Günther Ottendorfer explained that Sprint’s approach to carrier aggregation technology uses multiple bands inside its 2.5 GHz spectrum holdings, noting that Sprint could potentially offer up to four or five channels of service using carrier aggregation in its 2.5 GHz spectrum because Sprint owns roughly 160 MHz of 2.5 GHz spectrum in the nation’s top 100 markets.

Samsung also is likely to be the first handset vendor to come out with a model to support a new feature that Sprint started talking about late last year. In December, Sprint unveiled what it described as a breakthrough innovation specifically for TDD-LTE networks called High Performance User Equipment (HPUE), a type of power class certified by 3GPP on Dec. 6, 2016, that’s designed to provide better coverage and faster data speeds.

Sprint demonstrated the technology for media and analysts in New York City, showing the new technology is capable of extending its 2.5 GHz coverage by up to 30% to match its mid-band 1.9 GHz spectrum performance, including indoors. Sprint co-led the development of HPUE in conjunction with the Global TDD LTE Initiative (GTI) and companies such as China Mobile, SoftBank, Qualcomm Technologies, Samsung, ZTE, Broadcom, MediaTek, Skyworks Solutions, Alcatel, Motorola, LG and Qorvo.

Sprint expects Samsung to support HPUE in devices slated for commercial launch this year.