Nov 13, 2013
Qualcomm products mentioned within this post are offered by Qualcomm Technologies, Inc. and/or its subsidiaries.
In our fourth blog post on smartphone power and battery life, we will explore the innovations around connectivity and how they deliver a better user experience. Our previous posts can be found below.
- Smartphone Battery Life and SoC Power Benchmarking
- The Thermal Efficiency Behind Smartphone Trends
- Power vs. Performance Management of the CPU
This is a connected world. Most of us “possess within our pockets, a device that is capable of accessing the entirety of information known to man.” That is an impressive feat, enabled by some equally impressive technologies. Qualcomm Technologies, Inc. (QTI) continues to provide leadership in connected technology by pairing highly capable application processors with equally effective connectivity solutions including one of the most advanced generations of 3G and 4G LTE modems as well as GNSS location, and the latest Wi-Fi solutions. When packaged together, QTI processors offer some of the very latest in mobile computing and communications technology.
LTE Advanced Carrier Aggregation
Earlier this year at Mobile World Congress, QTI was the first to demonstrate the next generation of mobile connectivity with LTE Advanced Carrier Aggregation. Several months later, QTI was again first to commercialize that capability on a smartphone in the form of the Samsung Galaxy S4 LTE-A, powered by the Snapdragon™ 800 processor. The foundational feature of the LTE Advanced standard is carrier aggregation.
Carrier Aggregation (CA) helps combine the fragmented spectrum resources of wireless operators. Most operators are limited to relatively small chucks of spectrum of 10MHz or less. The narrower the band, the lower the bandwidth, and the lower the data speed. CA allows for the LTE modem to “aggregate” or combine two separate channels and treat them as one wider, faster channel. If used to combine two 10 MHz channels to form a wider 20 MHz channel, this feature is designed to double a user’s 4G data speeds, reaching up to 150 Mbps.
As one of the key benefits of LTE Advanced (or LTE-A), CA enables downloads to be completed nearly twice as fast as LTE. That means anything that is using data, including YouTube videos, Facebook pages, e-mail syncs, or web browsing, may load close to half the time of other 4G LTE modems. This directly leads to improved battery life, because when you can download content faster, the modem can go to sleep faster, thereby keeping your battery charged longer.
Another benefit of LTE-A is lower latency as compared to LTE. Think of latency as the time you have to wait in line at a grocery store for a cashier. While the latency of LTE on its own is much lower compared to 3G, LTE-A has even more “cashiers” to serve you. With more cashiers open, your wait time is dramatically decreased so you are served much faster.
LTE-A can also take the online mobile gaming experience to the next level. Low latency is essential to a great experience with fast-paced online games. In the case of first-person shooter games, LTE-A can mean the difference between life and death! Say you are playing Modern Combat 3. A fraction of a second in latency delay might mean your sniper shots are off target or you cannot get behind cover before that grenade goes boom. Armed with your rifle and LTE-A, you can show those n00bs who is 1337.
Many of our competitors are years and generations behind in their implementation of LTE standards. While several are still attempting to release their first generation product, QTI has already commercialized its third.
Envelope tracking is another recent Qualcomm Gobi modem innovation. This technology applies to the RF (Radio Frequency) power amplifier, designed to allow its voltage to be adjusted to match the envelope of the output signal so as to achieve higher power efficiency. Without Envelope Tracking (ET), the excessive power (shown in yellow below) is dissipated as heat. Snapdragon-powered devices with ET are designed to reduce the thermal footprint by up to 30% and RF power consumption by up to 20%. Snapdragon processors coupled with the industry’s first modem-assisted ET for 3G and 4G LTE devices are now commercial on the Samsung Galaxy Note 3.
End users should expect longer battery life and longer connections. Uploading your favorite photos and videos from your mobile device to the web will not only be faster but will no longer take an excessive toll on your battery, thanks to ET. The thermal reduction through reduced energy and heat also helps OEMs craft thinner and cooler phones. You can learn more about Envelope Tracking here.
Connected Mode Discontinuous Reception
Connected Mode Discontinuous Reception (CDRX) is a feature that can turn off the LTE receiver when communications are not being actively sent or received.
This can lead to significant system power savings of up to 15% lower power for web browsing and up to 20% for YouTube streaming. Simple as it sounds, CDRX implementation requires careful implementation, extensive testing, and optimization in the field to make sure this works as desired. There are a number of scenarios that need to be accounted for in design of CDRX. What if the network thinks your LTE receiver is “ON” while is it actually “OFF” and you end up missing an important call? By working closely with OEM and infrastructure vendors to test and enhance critical features such as CDRX on real-world wireless networks, QTI is enabling Snapdragon processors with the power savings you need without sacrificing your important calls or data.
Network Socket Request Manager
There is a downside to the fact that so many user apps are now data connected. The typical user has dozens of apps on their smartphone, many of which “phone home” or connect to the network several times and every hour. Apps for weather, news, and social networking attempt to sync for the latest updates and then disconnect shortly thereafter.
The problem is that each app schedules these connections independently of the others. These frequent and short connections force the modem to wake up and burn power. In addition, the connect-and-disconnect signaling can congest the network, slowing it down.
Network Socket Request Manager (NSRM), a proprietary QTI feature, is designed to effectively schedule and coordinate these access attempts, thereby reducing the time the modem is connected and awake. These connection attempts are “gated” through software for a configurable period of time. After that time has elapsed or the user brings the phone out of standby, the gate is opened, allowing the queued connection attempts from the apps to access the network as a single bundled batch versus allowing each app to connect individually. This is designed to reduce the number of connection attempts, reduce data sent, and reduce the signaling overhead.
QTI lab testing showed that “for a mix of twelve commonly used applications, NSRM achieves up to a 30% reduction in the number of connections per hour in the device.” In turn, that reduction also resulted in “up to a 30% reduction in standby power.” Such significant power savings in standby should accumulate during any “day-of-use” type scenario, since our phones are in standby mode the majority of the day. The data below highlights the additional benefit NSRM provides on top of standards-defined power-savings features. When it comes to saving power, Qualcomm Gobi modems are engineered to really go above and beyond the standards to improve battery life of your mobile device!
In addition, this feature will benefit everyone on the network. The heavy signaling from many apps on the sometimes already congested network negatively impacts the bandwidth available to everyone. By reducing the load on the operator, this can improve everyone’s speeds and overall user experience. Learn more in the technical NSRM whitepaper.
Location Services with iZAT
Qualcomm Technologies connects users through more than just the modem. The Qualcomm iZAT suite of technologies combines several global positioning satellite constellations, including Beidou, GLONASS, as well as the traditional GPS network. By using multiple services, iZAT is designed to pinpoint your location faster and more reliably, no matter where you are.
Headed indoors or deep inside the urban jungle? Qualcomm iZat uses Wi-Fi in addition to the built-in sensors such as a gyroscope, accelerometer and compass, to provide indoor location-based services. So whether you’re in a stadium, a shopping mall, a museum or an airport, surrounded by multiple layers of concrete, you’ll still be able to locate where you need to be with iZat.
You can learn more about iZat here.
Our next post will explore some of the new user experiences enabled by the powerful Snapdragon AP.