Ericsson is aiming to make mobile networks better at handling HD video by improving the performance of regular base stations and adding small cells in a coordinated way.
With less than two weeks to go before the telecommunications industry congregates at Mobile World Congress in Barcelona, Ericsson on Wednesday announced some of the products and technologies it will launch and demonstrate there.
The growing popularity of applications, including streaming video and music, that need a lot of bandwidth to work means operators have to rethink how they build their mobile networks, according to Ericsson.
To improve "app coverage" Ericsson suggests improving the existing network and adding small cells.
One way to improve network performance is to re-use GSM spectrum for use by 3G and LTE networks in a more efficient way, said Sebastian Tolstoy, head of radio strategy and business development at Ericsson.
Using a number of different technologies, Ericsson can carve out spectrum in the 900MHz and 1800MHz band for use by 3G and LTE while not affecting GSM voice quality. For example, a technology called VAMOS (Voice services over Adaptive Multi-user channels on One Slot) allows operators to double GSM's voice capacity without the need for additional transceivers.
To show how downlink bandwidth in HSPA networks can be improved, Ericsson and Qualcomm will demonstrate how an extra amount of bandwidth in the 1500MHz band can be used as a complement to existing frequency bands to improve downlink performance. The concept is called supplemental downlink and the result is up to a 150 percent improvement of data rates at the cell edge, according to Tolstoy.
Vendors trying to show off their technical prowess using demos of what they're working on is a recurring part of Mobile World Congress. This year Ericsson will show how bandwidth can be increased to 1G bps by using eight antennas in a tablet. Sending and receiving data using multiple antennas is possible thanks to a technology called MIMO (Multiple-Input Multiple-Output), which is already used in both Wi-Fi and LTE networks.
In addition to MIMO, Ericsson will also use a technology called carrier aggregation, which is part of LTE-Advanced and speeds up networks by combining two or more swaths of bandwidth into one channel in the same or different frequency bands.
The company will also conduct a separate bandwidth aggregation demo using commercial devices and chipsets from Sierra Wireless and Qualcomm. Bandwidth will increase to 150M bps, thanks to the use of two times 10MHz of spectrum for download traffic, according to Ericsson. Today operators like Verizon Wireless in the U.S. and Everything Everywhere in the U.K. today use 10MHz of spectrum for download traffic.
The addition of these technologies over time will still not be enough for networks to handle growing data volumes. Small cells working together with existing base stations are needed for that, according to Ericsson.
"We believe that its most efficient to add small cells in very specific areas, such as stadiums or large indoor shopping malls ... What we don't recommend is deploying small cells in an uncoordinated way," Tolstoy said.
By coordinating the roll-out of small-cell coverage, capacity improvements will be bigger. With a so-called combined cell, which is also part of LTE-Advanced, the same spectrum can be used for base stations and small cells without interference ruining the performance. That will also be demoed at Mobile World Congress.
One thing Ericsson didn't talk about during its London event on Wednesday was its products and plans for using Wi-Fi to help offload cellular networks.
While data communications is rightfully getting a growing amount of attention, telephony is still the biggest revenue generator for mobile operators. At this year's Mobile World Congress, VoLTE (Voice over LTE) is expected to be one of the big trends, as operators are getting ready to launch commercial services.
"What we will show this year in Barcelona is the maturity of VoLTE," said Magnus Furustam, vice president and head of Ericsson's Core and IMS product area.
That includes the world's first LTE-FDD (Frequency-Division Duplex) to LTE-TDD (Time-Division Duplex) voice call with China Mobile, ST-Ericsson and device partner Renesas Mobile. LTE-TDD uses one channel for both upload and download traffic, compared to LTE FDD, which uses separate channels for download and upload traffic.
As of early January, 13 commercial LTE-TDD networks have been launched in countries such as Australia, Brazil, India, Russia and the U.K. That compares to more than 10 times as many networks based on the FDD version on LTE, according to industry organization GSA (Global mobile Suppliers Association).
Three in Sweden and Aero2 in Poland already use both versions in their networks. That is also what U.S. operator Sprint would be able to do if its acquisition of Clearwire is approved. Operators in China and India are also planning to use a combination, according to Ericsson.
"It is important for us to show that we can have a seamless service between these two variants," Tolstoy said.