In the process of writing this blog I tried to present you the importance of WBAN 802.15.4 standard in its 2010 version. I hope that I managed to at least direct the reader in proper direction of investigating the way it’s being standardized and how it will influence the market and society. In this post I will gather this information in a more compact form.
This summary will be divided into several parts:
What is WBAN
- Medical usage
- Sport usage
How it works?
How is it different from previous version?
What about competition?
Why is it going to be the successive?
What is WBAN?
WBAN as a shortcut of Wireless Body Area Network (or sometimes called Wireless Personal Area Network) is a network of nodes that are deployed on the surface of a person’s body. The number of nodes is normally in range of 10-20 on one person. The most important use of such a network is to measure different markers of the person under test and send this data to the main node. Of course this main node can send this data to remote location with use of any of available ambient networks (GSM, WIFI, satellite etc).
The biggest requirement for such inter-node communication is to keep the power usage as low as possible, this is connected with actually two reasons – to assure long operations (battery life) and to limit the radiation to which the person is subjected. This second reason is especially important in cases where the use is prolonged and the person under test is a hospital patient, where radiation over long period of time could lead to some additional illnesses or at least result in change of medical test results.
With the direction of modern technology evolution we can expect that, what was previously only possible in sci-fi movies, will become normality. People will be connected to the grid gathering information about their state of health, their location or mood. The possibilities are endless, but in current state of this technology it’s most appealing in three interesting aspects:
Hospitals and health care in general are places where technological development has a very welcoming ground. It’s is here, where the idea of WBAN’s have the beginning. This solution will have a great application in constant wireless monitoring of patient’s health condition, their vitality and even habits. Each of patients’ could have several nodes, each placed in the most appropriate place on the body and each testing its specific parameter. With such information, especially in long term monitoring, doctors could really make diagnosis based on more information than before.
Also in this category we can see the solutions to monitor people at home, especially elderly people, who can’t fully control their situation, and sometimes need additional help.
This application is dramatically different. It’s directed on young active people, who exercise a lot, and who would like to have accurate and constant information about their training progress. In this category we could list a big number of different nodes that can give useful information, but just to mention the most important: heart beat sensor, pedometer, temperature sensor, integrated bike sensors (speed, cadence etc). This application is even more important than one could think, as people actively exercising are mostly young, well situated and educated, and what’s most important not afraid of new technologies, maybe even fond of the gadgets they use.
There are hundreds of ideas how to use WBAN technology. We can see a future of modern clothing with this radio communication embedded, we can see it as a way of keeping all of our devices in synch, but also it can be used as the modern solution on the areas of war conflicts. Army already was developing this kind of technology for several years, but it’s possible that if the commercial standard will give it even more possibilities and performance, we can see interest in this standard also from that direction.
How it works?
The most important part of this standard in technical aspect is the physical medium of communication. As the wireless nature of communication can bring totally different results depending on the specific technology used, it is crucial to choose it wisely.
In case of 802.15.4 standard (2010 version), we can use three different radio communication specifications: Ultra wide band, Narrow band, Human Body Communication. It’s important to note first and last one of them. Ultra wide band transmits data with very little power but on a very broad frequency band – it gives two advantages: it’s very hard to interfere with this signal, and this signal is very improbable to interfere with any other device. It’s especially important for use in medical applications, where any interferences with a life support systems can have a catastrophic effect.
Second kind of radio interface has a very different advantage: it’s construction is as simple as possible. There is even no parts responsible directly for RF mixing- everything until the antenna is done in digital domain, using special kind of bit arrangement.
This standard actually doesn’t limit its scope to RF part. 2010 version is also focused on delivering full solution for WBAN networks. We can see that the network topology is described as start network, but we could also expect to see a development of standard to use a multi hop network. Security features and MAC layer are also being described, to get the standard on the level which will allow all the manufactures to build a network of devices fully compatible with each other – the main idea behind standardizing WBAN in such a shape.
How it differs from previous version?
Previous version was a basis for ZigBee standard. It was only focused on the part of MAC layer and physical description medium (RF part). It was limited in its description of higher services and aspects. For example there was no network topology except point to point communication. That meant that for a fully operational product for WBAN applications, there was a need for further specifications of these aspects. ZigBee was such an attempt, but it was done several years ago. As the technology went further the development of new version was decided to be the best option. In this sense currently the focus of standard was broadened and will cover also higher parts and services of protocol.
That means that we will have a standardized in full WBAN communication with more complicated network topology and security. It’s the biggest difference that now it won’t be necessary to build additional standard on top of 802.15.4.
Also with new version, as it was described in previous paragraph, two new radio communication mediums were described – UWB and HBC, which brings new big improvements.
What about competition?
There is only one real competition for new 802.15.4 standard- an old 802.15.4 standard with its ZigBee addition. It can be a hard question in which way market will turn in few years, especially due to high interest in ZigBee between industry companies. In my belief advantages of new standard will make the change easier and industry will be more eager to switch.
Until the standard is fully described, or at least there is draft finished, it’s hard to divagate on the topic of how big difference will new 802.15.4 make, but we can only hope that it will be important enough to make ZigBee follow its lead.
Also there are several more standards of wireless communication for short distances, but actually they have not so much focus on the topic of power efficiency – Bluetooth or WiFi limit usage time of use even for a fairly big and complicated smartphones, not to mention small and cheap WBAN nodes. Thus the choice of WBAN standard in future will be between old and new 802.15.4.
Why is it going to be a success?
Modern world, even if it’s not fully aware of that fact, needs an introduction of WBAN’s to mass usage. As idea behind WBAN can only be realized when each device can communicate with each other, the process of standardization is a fundament on which the whole technology will be built. I believe that with a proper standard, which current draft can become, this technology has a very bright future. ZigBee is not that well situated on the market outside of industrial solutions of building monitoring, so it’s longer existence on the market may not have so big influence on the choice which will have to be made in the future- old or new 802.15.4. The advantages of new version can be seen very easily, so I think the end result will be in its favor.