By Brian Blum, Texas Instruments

Bluetooth Low Energy (BLE) is fast-becoming the hottest buzz-word in low-power wireless communications. Within five years, we have seen a variety of standard and proprietary networking protocols emerge, begin to show promise, and occasionally open up new market spaces and fundamental opportunities for technical innovation. Is BLE just another low-power radio frequency (RF) networking protocol or something new to get excited about?
BLE Enters the Low-Power Wireless Arena
Bluetooth Low Energy – Not Just Another Radio Frequency Networking Protocol

Figure 1. BLE-slave heart rate sensor data stored on BLE-master watch.
Existing and emerging RF networking wireless protocols are seen increasingly at trade shows and are appearing in products sold in diverse worldwide markets. Z-Wave battles ZigBee HA for control over the home automation market. ZigBee PRO Smart Energy gains continued acceptance from states, utility companies and nations worldwide. ANT builds momentum in the sports and fitness arena. RF4CE promises to replace the hundreds of millions of feature-enhanced, two-way functionality infrared remotes. Many other proprietary and standard networking protocols (e.g., WirelessHART, 6LoWPAN, SimpliciTI) continue to show promise across an expanding range of markets including medical, industrial, and commercial building automation and control. These technologies are also being applied to help resolve critical world concerns including homeland security and environmental monitoring. Given this growing ecosystem of low-power wireless technologies, is it necessary to adopt yet another low-power RF standard or technology?

Bluetooth Low Energy (BLE), formerly Nokia Research's Wibree protocol and after that, Ultra Low Power Bluetooth, is a new low-power, open, RF networking standard under development by the same team that developed the "classic" Bluetooth technology (Bluetooth SIG) found in most of today's cellular phones, laptops and even automobiles. BLE is designed to enable connectivity of power-sensitive devices operating on primary cells – alkaline or coin cells – for long periods of time ranging from months to potentially several years. The Bluetooth creators recognize and are responding to the need and opportunity for an open wireless network focused on very low-power, low-cost operation in relatively close proximity to the user. This personal area network, or PAN, is capable of piggy-backing on existing Bluetooth technology's popularity and ubiquity.
A Uniquely Different Standard
What potentially may make BLE truly unique in the wireless sensor network technology space is its ability to take advantage of existing worldwide annual Bluetooth bit rate/enhanced data rate (BR/EDR) device sales. BLE was designed so that new Bluetooth chipsets with only very minor modifications to the PHY and virtually no additional silicon cost will be able to operate as dual-mode devices. These devices will continue to support existing Bluetooth BR/EDR technology, while enabling operation as a master to a BLE single-mode slave. In other words, Bluetooth dual-mode devices are those that can operate as both traditional Bluetooth master/slave devices, as well as BLE masters. A single-mode device, however, will support only the new BLE standard (both master and slave roles supported) and will remain simple, low cost, and consume less power.

Several of the biggest Bluetooth chip suppliers, including Texas Instruments, are committed to integrating dual-mode technology into tens of millions of devices beginning in 2010. This commitment will help to ensure an infrastructure that will support the launch of BLE in the sensors and fitness, healthcare, mobile accessory, home and entertainment, automotive, and watch and wearable device markets. The short lifetime of most cellular and smart phones should contribute considerably to the relatively quick and massive infrastructure deployment necessary to enable the adoption of BLE sensors and other single-mode devices.
A Smart, Low-Power Fit
One of the most likely set of products to take off during BLE's early inception is within the fitness and sports arena. Sports performance monitoring devices allow you to count your daily number of steps, monitor and record heart rate throughout workouts or periods of physical activity, track specific workout routines in gyms and fitness clubs, and utilize intelligent weight scales or performance analysis equipment. Wireless-enabled performance monitoring devices can connect all of this equipment seamlessly through a gateway device to make use of the information gathered.

This gateway can be a cell phone or PC that connects back to the Internet where the information can be saved and later analyzed as part of a weight loss or health program, or possibly by your doctor, physician or coach. Utilizing a cell phone's dual-mode capabilities coupled with new single-mode BLE sensors can lead to a better understanding of an individual's health and lifestyle.

The medical, healthcare and assisted living markets can utilize BLE to monitor vitals for the elderly or those with health ailments or diseases such as diabetes. Throughout the home or within an assisted living center, BLE can be used to enable novel sensor and actuator technologies that can transmit data back to a central monitoring station. This action can be accomplished through the existing cellular phones or Bluetooth-enabled PC infrastructure. Sensors would monitor blood pressure, real-time blood glucose levels, motion within the home, or the taking of medication. Actuators could dispense medication, issue reminders to exercise or wash, and open doors using secure identification via a watch or other wearable device. While other low-power RF technologies can solve this problem using deployed infrastructure, BLE offers connectivity through already existing dual-mode, Bluetooth-enabled cellular phones. As a result, it can be less costly and easier to provide a family member with daily updates or contact an emergency dispatch service should a problem arise.

BLE technology can also offer a low-cost, low-power interface to a cellular phone, laptop, or other Bluetooth-enabled products. Dual-mode BLE capabilities integrated into cell phones will allow for watches and other personal user identification (PUID) devices to manage cell phone functions. This includes using your watch to monitor caller ID, mute or ignore a call or to silence your ringer when your phone is in a hard to reach place. Proximity functionality designed into your BLE watch or cell phone will enable security and tracking capabilities beneficial across a range of markets. A BLE watch can be used to lock your laptop when you walk away and unlock the laptop when you return. Tagged items such as your wallet, car keys or even a child could be monitored so that a warning is issued as soon as these devices or persons are "out of range".

There are potentially far more products, markets and breakthrough technologies that BLE technology enables. What is most important to remember is that the technology goes beyond yet another short range radio frequency standard. BLE technology takes direct advantage of the prolific rollout of dual-mode support in cellular handsets because the infrastructure will already be in place – at no additional cost – to interface to sensors and actuators within your personal space. This means that wherever you go the data that your BLE-enabled devices collect or the actions they take can be recorded, sent back to the internet, and later viewed or analyzed. Low-power BLE devices will be very small and battery replacement will be rare. If you carry a cellular phone today, chances are that by 2011 you will already be carrying BLE technology.

To learn more about Bluetooth Low Energy, visit:

Brian M. Blum is a ZigBee product marketing engineer with Texas Instruments where he is responsible for 802.15.4 and ZigBee Low Power RF product line. He received his Master's of Computer Science with a focus on Wireless Sensor Networking from University of Virginia. Brian can be reached at