In late 2006, Finland’s Nokia announced Wibree, a new short range wireless technology it had developed to enable short-range communication between electronic devices. The crucial difference between Wibree and existing Bluetooth technology is that Wibree ran on as little as one tenth the power of Bluetooth.
What is Wibree?
Wibree is a digital radio technology (intended to become an open standard of wireless communications) designed for ultra low power consumption (button cell batteries) within a short range (10 meters / 30ft) based around low-cost transceiver microchips in each device.
Wibree, also known as Bluetooth Ultra Low Power, consumes only a fraction of the power compared to other such radio technologies, enabling smaller and less costly implementations and it is easy to integrate with Bluetooth solutions.
Origins of Wibree
In 2001, Nokia researchers determined that there were various scenarios that contemporary wireless technologies did not address. To address the problem, Nokia Research Center started the development of a wireless technology adapted from the Bluetooth standard which would provide lower power usage and price while minimizing difference between Bluetooth and the new technology. The results were published in 2004 using the name Bluetooth Low End Extension. After further development with partners, e.g., within EU FP6 project MIMOSA, the technology was released to public in October 2006 with brand name Wibree. After negotiations with Bluetooth SIG members, in June 2007, an agreement was reached to include Wibree in future. Bluetooth specification as a Bluetooth ultra-low-power technology, now known as Bluetooth low energy technology
Wibree: Technical Specifications
Wibree is similar in many respects to the now prevalent Bluetooth standard. Both use the 2.45 GHz band to transfer data and have a 1 Mbps transfer rate (although the newer Bluetooth 2.0 standard already incorporates a 3.0 Mbps transfer rate) and a rage of about 10 meters (m). The two complementary technologies differ in size, price, and most of all power consumption. Wibree would use only a fraction of the power consumed by today’s Bluetooth chips, resulting in a much longer battery life and more compact devices. While Bluetooth can be used to transmit audio and media files, Wibree is designed to extend this network by serving applications that transmit only small amounts of data and where size and cost are priorities. Many applications that were not cost-effective using existing Bluetooth technology, such as wirelessly controlled toys, watches, medical and sports sensors, and a range of other applications that have not been conceived yet, might be developed using Wibree technology
There are two types of Wibree implementations –one based on the Wibree standalone chip, and another based on the Wibree-Bluetooth dual-mode chip – which serve different purposes and are installed on different devices. Stand-alone Wibree chips would be implemented in small, low cost devices such as wireless mouse and keyboards, sensors, and toys. The Wibree-Bluetooth dual-mode chips are in mobile phones, allowing users to benefit from both worlds – Bluetooth 2.0 high speed and Wibree’s low power and extended ability to communicate with a new generation of smaller wireless devices.
There is an irony in the fact that the origins of Wibree were the alternative proposal for the radio and Media Access Controller (MAC) for the 802.15.4 standard, which is now the basis of ZigBee and other short range radio networks.
Wibree comprises a physical layer, light weight protocol stack and application-specific profiles. It is designed to connect mobile phones and PCs to a range of coin-cell battery-powered devices that require battery lifetimes of years. Nordic Semiconductor became one of the first members joining the Wibree open initiative and is member of the Wibree specification group. Other members include CSR, Broadcom, Epson, Suunto, and Taiyo Yuden.
The specification details a short-range RF communication technology featuring ultra low power consumption, a lightweight protocol stack and integration with Bluetooth. Wibree operates in the globally accepted 2.4 GHz ISM (Industrial, Scientific & Medical) band. It features a physical layer bit rate of 1Mbit/s over a range of 5 to 10 meters. The specification features two implementations: dual-mode and stand-alone. In the dual-mode implementation, Wibree functionality is integrated into Bluetooth circuitry.
Wibree is designed to work side-by-side with and complement Bluetooth. It operates in 2.4 GHz ISM band with physical layer bit rate of 1 Mbit/s. Main applications include devices such as wrist watches, wireless keyboards, toys and sports sensors where low power consumption is a key design requirement.
Wibree is not designed to replace Bluetooth, but rather to complement the technology in supported devices. Wibree-enabled devices will be smaller and more energy-efficient than their Bluetooth counterparts. This is especially important in devices such as wristwatches, where Bluetooth models may be too large and heavy to be comfortable. Replacing Bluetooth with Wibree will make the devices closer in dimensions and weight to current standard wristwatches.
Wibree Implementations
There will be two types of Wibree implementations: – one based on the Wibree standalone chip, and another based on the Wibree–Bluetooth dual-mode chip – which will serve different purposes and be installed on different devices.
Stand-alone Wibree chips would be implemented in small, low cost devices such as wireless mouse and keyboards, sensors, and toys. The Wibree stand-alone chip is designed for use with applications which require extremely low power consumption, small size, low cost and where only small quantities of data are transferred. It’s an ideal solution for small devices (like heart rate monitors) that use only short data message and must have long battery life. Examples of devices that would benefit from the Wibree stand-alone chip are: watches, sports and wellness devices and human interface devices (HID) such as wireless keyboards.
The Wibree-Bluetooth dual-mode chips would probably be implemented in future mobile phones, allowing users to benefit from both worlds – Bluetooth 2.0 high speed and Wibree’s low power and extended ability to communicate with a new generation of smaller wireless devices. The Bluetooth-Wibree dual-mode chip is designed for use in Bluetooth devices. In this type of implementation, Wibree functionality can be integrated with Bluetooth for a minor incremental cost by utilizing key Bluetooth components and the existing Bluetooth RF
Wibree vs. Bluetooth
Wibree differs from Bluetooth in several fundamental ways.
- Data Transfer Speed: Recent Bluetooth specifications, notably 2.0, are designed with an emphasis on throughput, or data transfer speed. Bluetooth 2.0 devices can exceed speeds of 350 kb/s under ideal conditions. This is about three times the maximum speed of planned Wibree devices, which transfer data no faster than.128 kb/s. The tradeoff comes to light in terms of power, space and weight savings. Current Bluetooth-enabled wristwatches must replace their large, specialty batteries on a monthly basis.
- Use of Frequency Hopping: Bluetooth uses a frequency hopping technology to avoid interference from other devices operating in the same frequency. Wibree does not use frequency hopping.
- Packet Length: Bluetooth uses fixed packet length. This increases power usage as unnecessary transmission occurs. Wibree has a variable packet length and transmits only when necessary.
- Battery Usage: Bluetooth drains your cell phone battery as it needs quite a lot of power to remain active. Wibree aims to survive for a full year on a button sized battery. In contrast to Bluetooth, Wibree goes into sleep mode when not transmitting. In sleep mode the radio will be off and will save a lot of power. Wibree devices wake up only when they want to transmit.
- Traffic Characteristics: The major usage difference between Wibree and Bluetooth is the traffic characteristics. Bluetooth is useful when transferring files, using the hands free etc where the volume of data that needs to transferred is considerable.
- Type of Data Transferred: Wibree is used in areas where only short bursts of data need to be transmitted. Remotes, sensor data etc.
Wibree Applications
Imagine a wireless keyboard and mouse with battery lifetimes exceeding one year communicating with a PC without using a fragile dongle. Imagine a watch equipped with a wireless link communicating with both a tiny sports sensor embedded within the user’s shoe and mobile phone. Imagine a range of personal devices communicating with mobile phones or PCs, but without the inconvenience of changing or charging batteries every week. Imagine no longer, because Wibree will make all of these applications – and many more – a reality.
Mobile phones equipped with Wibree will enable a range of new accessories such as call control/input devices, sports and health sensors, and security and payment devices with battery lifetimes of up to three years (depending on usage pattern). Wibree will also bring wireless connectivity to high-performance PC accessories such as mice, keyboards and multimedia remote controls with battery lifetimes of up to a year. And Wibree will add wireless connectivity to watches and sports sensors (for example, heart rate monitors) without significantly compromising battery lifetime.
Mobile Phone Accessories – Mobile phones equipped with Wibree technology will enable a range of new accessories such as call control/input devices, sports and health sensors, security and payment devices. These devices will benefit from the ultra-low power consumption of Wibree making possible compact, coin cell battery operated devices with battery lifetimes up to 3 years (depending on the actual application).
PC Accessories – Wibree is designed to offer wireless connectivity to high performance PC accessories such as mice, keyboards and multimedia remote controls. The ultra-low power consumption of Wibree extends battery lifetimes to over a year. Nordic will build on its position as a leading provider of ultra-low power 2.4 GHz technology to encourage Wibree’s adoption into PC accessories enabling the next generation of wireless mice and keyboards.
Watches – Imagine your watch equipped with a wireless link communicating with both a tiny sports sensor embedded in your shoe and your mobile phone.
Advantages of Wibree vis-à-vis Bluetooth
Wibree is the first wireless technology to solve the following needs in a single solution.
- Ultra low peak and average power consumption in both active and idle modes.
- Ultra low cost and small size for accessories and human interface devices (HID).
- Minimal cost and size addition to mobile phones and PCs.
- Global, intuitive and secure multi-vendor interoperability.
Disadvantages of Wibree vis-à-vis Bluetooth
Data transmission is very slow, i.e., only 1 megabit per second. Also, Wibree cannot be used in high bandwidth required applications.
Wibree will also dramatically extend the battery lifetime of existing wireless device such as keyboards, mice and remote controls. It’s up to 10 times more energy efficient then Bluetooth. Nokia said it expected the first commercial version of the standard to be available during the second quarter of 2007. The firm said it expected dual Bluetooth-Wibree devices such as mobile phones to hit the market within two years.
Summary
Wibree and Bluetooth both operate at 2.4GHz and have a similar range of around 10m, but the difference between the two lies in the continuity of the data being transferred. While Bluetooth is suited to constant uses such as streaming data or voice connectivity, Wibree is being touted as ideal for infrequent bursts of data — where the connected device will need to consume much less power.
Bluetooth and Wi-Fi are both wireless networking standards that provide connectivity via radio waves. The main difference: Bluetooth’s primary use is to replace cables, while Wi-Fi is largely used to provide wireless, high-speed access to the Internet or a local area network.
Wibree radio technology complements other local connectivity technologies, consuming only a fraction of the power compared to other such radio technologies, enabling smaller and less costly implementations and being easy to integrate with Bluetooth solutions.
Wibree is the first open technology offering connectivity between mobile devices or Personal Computers, and small, button cell battery power devices such as watches, wireless keyboards, toys and sports sensors. By extending the role mobile devices can play in consumers’ lives, this technology increases the growth potential in these market segments.
Bluetooth wireless technology is a short-range communications technology intended to replace the cables connecting portable and/or fixed devices while maintaining high levels of security. The key features of Bluetooth technology are robustness, low power, and low cost. The Bluetooth specification defines a uniform structure for a wide range of devices to connect and communicate with each other.