We are off to London this week for the Small Cells World Summit (June 9-11, ExCel Exhibition Centre). At the show we’ll be talking about extending LTE to unlicensed spectrum (LTE-U) and demoing LTE-U showing the combination of licensed (band 2, 1800 MHz) and unlicensed (5 GHz) channels using Qualcomm Technologies, Inc.’s commercial small cell system-on-chip (SoC), the FSM9955, in conjunction with user equipment (UE).
LTE-U and Licensed-Assisted Access (LAA) augment existing LTE services by utilizing 5 GHz unlicensed spectrum. Extending the benefits of LTE to unlicensed spectrum provides:
- Higher gains with longer range, more capacity and overall better performance than either LTE or Wi-Fi used individually;
- An enhanced, seamless user experience of reliable and predictable performance with an anchor channel in the licensed spectrum;
- And, additional capacity for carriers to augment mobile broadband globally in a cost-effective manner.
The frosting on the cake: all of this is achieved while still being a “good neighbor” to Wi-Fi (in many cases, even better than Wi-Fi itself). LTE-U and LAA use several coexistence features to support fair share use among the multiple users and technologies that access those bands.
Let’s dig in to these benefits a little more. Globally, LTE has more than 20 different bands. To enable higher data rates, fragmented and discrete bands must be aggregated. These bands differ by geography and often by individual operators within a given region. LTE-U and LAA provide the opportunity to aggregate up to 40 MHz contiguously in 5 GHz while keeping an anchor in licensed spectrum.
Also, 5 GHz is global, which means that RF components such as RFICs, filters, LNA, etc., can enjoy the scale that other unlicensed technologies enjoy. This can reduce the cost per Mbps of access points.
But, in order to provide maximum benefit, LTE-U must operate harmoniously alongside billions of existing Wi-Fi devices. Qualcomm Technologies has been working to integrate LTE and Wi-Fi at the system level to promote the best possible co-existence between LTE-U and Wi-Fi networks. Engineers at the company recently deployed a state-of-the-art network comprising multiple Wi-Fi access points and LTE-U small cells—all operating in a single channel in the unlicensed 5 GHz band—to evaluate real-life performance and interference in multiple scenarios. Testing scenarios included both “adaptive duty-cycle” based coexistence, which is suitable for commercial LTE-U deployments in countries such as the U.S., China and Korea, using LTE Release 10 and beyond. LAA, which is being standardized in 3GPP for use in regions such as Europe and Japan, utilizes Listen Before Talk (LBT) based techniques to sense energy and decode preambles.
After extensive testing that replicated extremely dense radio conditions, the data concluded that LTE-U can not only provide superior performance than either LTE or Wi-Fi used individually, but fairly coexists with Wi-Fi. In many cases, shifting traffic from Wi-Fi to LTE-U can actually improve performance for Wi-Fi users, due to the efficient way that LTE uses the unlicensed spectrum.
At the Small Cells World Summit this week we’ll be demoing some of these innovations, showing how operators can make unified use of available spectrum to help increase capacity for easier, more cost-effective network deployment and operations for carriers while providing a seamless experience for their consumers. We'll also be showcasing products developed by our partners based upon the FSM family of small cell SoCs. Stop by and see it for yourself at stand #69.