Wireless and Healthcare: the Perspective of a Long Journey.

So far, by writing this blog I have approached for the first time a new eHealth ecosystem and I have blogged about wireless technologies that are being implemented every day more.
I started form analyzing the simple word “eHealth” and I ended up discovering a whole new endless wireless world. I discovered that eHealth is a tangible reality, I realized that power consumption is the key consideration for selecting a wireless standard for medical devices and I understood the relevance that Bluetooth technology has gained through the years. On the other hand I discovered that no matter how brilliant your wireless technology is, long implementation cycles, government regulations, interoperability and standardization can slow down the entire process. Furthermore if we consider the healthcare scenario, these problems are even more accentuated since choosing a wireless technology for a wireless health system needs to consider a variety of requirements. It’s not simply deciding a wireless standard for a communication, but it’s the selection of a robust wireless technology that will assure efficiency, correct monitoring/surveillance and principally will not increase life risks of users. It needs to support different connections topologies such as LAN, PAN and WAN if you want to ensure that interoperability is present. The wireless technology should also be easily accessible by users thus, ubiquity is another key feature that should be considered in the process. From what I wrote until now one thing is obvious to me: Bluetooth is the answer. To achieve a good number of users, to reduce the growing costs of healthcare, eHealth needs a widespread of mass devices. According to IMS Research [1] in 2012 over 35% of smartphones will be shipped with dual-mode Bluetooth low energy and two thirds of the 821 million smartphones shipped in 2013 will include Bluetooth Smart Ready (Bluetooth 4.0). Today no other wireless technology can take this place, particularly in the eHealth sector. That’s why the world around Continua’s Alliance keeps on changing with the technology advancements. The decision to select Bluetooth Smart in the 2012 Deign Guidelines didn’t come by chance but was the final result of the collaboration with the Bluetooth Special Interest Group to make Bluetooth Smart devices “Continua-oriented”. Continua is focusing on compatibility to ensure interoperability between devices that use different versions of guidelines, but at the same time is always directed towards innovative wireless solutions. For Continua Alliance moving from using Classic Bluetooth to the latest Bluetooth Smart was a direct consequence of the medical industry requirements: ultra low power consumption. Therefore technically speaking the solution is not hard to find. The problem is more related to regulations placed on medical devices and excessive costs of certification; this will probably slow down the full adoption of the Bluetooth technology, while will consolidate the support of the Classic Bluetooth. Additional acceptance problems are deriving for the smartphone system; while Apple and Microsoft have decided to support Bluetooth 4.0 technology, Google with the Android 4.0 platform[1], doesn’t seem to agree. This decision can affect the adoption of Bluetooth Smart Devices in a long term since except from the Apple iPhone 4S, all smartphones that are inclusive of the Bluetooth Smart Ready are using Android platform. Finally, security can also be an obstacle to Bluetooth technology for eHealth systems. A lot of improvements in terms of security have been done in the version 4.0 of Bluetooth [3], but also here, for example the protection against hacking is automatically available only for the latest version of Bluetooth. Considering the relevance that Bluetooth technology is having for the eHealth sector, a coherent approach is needed to protect data and to prevent from misuse of medical records.

Since Bluetooth technology was adopted all the effort was oriented to increase data rates, but today we understood that is exactly the opposite, that is low data rates, that is going to make this technology important. Of course, problems are still evident in the eHealth sector but don’t tell me that ultra low power, smart wireless technology that creates an impressive range of new healthcare markets isn’t enough for eHealth standardization.

References:
[1] http://imsresearch.com/press-release/Bluetooth_Smart_To_Be_the_Wireless_Technology_Most_Used_in_Consumer_Medical_Devices_by_2016&cat_id=188&from=
[2] http://imsresearch.com/press-release/Is_the_Google_Platform_Delaying_the_Bluetooth_Smart_Train&cat_id=188&from=
[3] "Analysis of Bluetooth Threats And v4.0 Security Features " , International Conference on Communication Computing and Applications (ICCCA 2012), 23rd - 24th February 2012, PSNA College of engineering, Dindigul, IEEE Xplore

The risks of Standardization and IP Protection.

The Continua Health Alliance has been working on creating a network of standards, drawing on the IEEE for standardized data formats and wired wireless standards groups to define the connectivity level over which the data can be transported. Their choice of wireless standard is the BL LE, which is already present in the majority of smartphones. Despite the technical reasons that make the Bluetooth Low Energy a good candidate for the eHealth systems, it is obvious that Continua ended up by selecting this standard simply because it is the one that manufacturers include mostly in their handsets.

The work of the GSM Association will certainly increase the role that mobile phones are going to play in the broadband structure. As a consequence, this will increase in terms of billions the number of broadband mobile phones that will include the Bluetooth Smart technology. The deeper meaning of this forecast is that clearly, the technology selection for a wireless health product will be impersonally made by product manufacturers since the market will ask for healthcare devices that have something to connect to. The role of regulators is limiting the manufacturers, as we already saw when considering the role of the FDA, but what can be considered a real risk in terms of costs for healthcare manufacturers, is the selection of a standard that is strictly connected with Intellectual Property disputes. The conflicts connected with the Intellectual Property can constitute a real risk for the system. In a public document, the Bluetooth SIG mentions that from the IP viewpoint, wireless standards are not equal. As the importance of wireless standards starts to increase, the concerns connected to Intellectual Property starts to increase exponentially, as already happened with patent trolls attacking ZigBee and Wi-Fi. The principal problem is that most people not consider Intellectual Property rights when undergoing through a standardization process [1]. There is the stupid conjecture that if a standard is selected, then as long as you have the right to use it there are no related IP problems. Not even the standards bodies, such as ETSI and IEEE give any IP assurance, which means that a lot of companies have been taken to court, only because of their ignorance. This lack of knowledge can cost to a company millions of dollars. Therefore, for the eHealth system is important to understand that the existence of a standard does not give to a company a free right to automatically possess  the IP within it. If we consider the two standards selected by Continua Health Alliance, Bluetooth Low Energy and ZigBee, they both impose to the company that uses the standard in their product to sign a member agreement, which contains a clause of IP ownership. To be more precise, this is connected with the concept of Necessary Claims; once the company decides to signup because has the necessity of that specific technology, it also gives up the right to claim for the violation of any IPR the company itself might own, which is used by other companies developing the standard. For example, in the Bluetooth technology you cannot ask for a fee for anyone using your IPR as complement of the standard, and this license is defined as RANDZ (Reasonable and Non Discriminatory- Zero cost). When considering the ZigBee technology the situation is different, because in theory it is possible to charge a fee for other ZigBee companies, and this is defined as a RAND license (Reasonable and Non Discriminatory).

Is this a good approach for Intellectual Property rights? I think it has a double- sided result: on one side, companies agree to not sue each other, but on the other side they give away part of the value of their IP. Basically, the problem is that is quite hard for industries to estimate the value that the IP use can have as a competitive tool. When a company signs this sort of agreement, it is also signing up to legally provide the future use of its IP that might be extremely valuable in the future. This means that a company with a conservative approach to IP, can prefer to take a conservative position and not sign. Before a standard is finalized, most of the standards groups do an IP evaluation to understand if there can be any problems from patents owned from outside the standard body. But of course none of the standards organizations give immunity to risks. When approaching to a standard, how can a company analyze the risks?

The first thing to do when selecting a standard is to look at how much that standard covers. Besides the largest adoption on smartphones, one of the major reasons behind the adoption of Bluetooth as a standard by Continua, is the fact that the Bluetooth specifications are very exhaustive starting from the radio specification going through the application profile. This means that all elements of the standard are included in the ember IP agreement. Instead, ZigBee agreement provides no IP cover for  the specifications, since it use external standards like the IEEE 802.15.4 for the radio and baseband layer. The main idea is that a standard can only offer IP protection for the parts it own.

 

Standards and IP protection

The more companies one can get to sign for the IP license, the more protection is ensured from prosecutors. Bluetooth is extremely good in convincing companies to sign the IP license, as they have over 13,000 members. Z-Wave is a standard created exactly to cover the full range from radio to application. The reason why this standard has not the same popularity of Bluetooth, is connected to the fact that only one company is the owner of the Z-Wave IP. Additionally, this standard can’t count on the security of having 13.000 contributing members for its IP, which instead Bluetooth has. Standards like Z-Wave haven’t contributed to the market enough to make it worth suing or attacking them with patent trolls. Also the presence of a standard in the market is essential to determinate possible risks; Continua is very well aware of this and since Bluetooth has been around longer than other standards, it ensures that the standard is safer and has more members. As a conclusion we can state that more recent standards are more risky. The Bluetooth Low Energy, despite being considered a recent standard, is a rather straightforward process, because it is a company-based standard that can count on the security and wide membership of a standard like Bluetooth. This is a key attribute for the selection of the BL LE technology as de facto standard for the health devices by Continua Alliance. Surely, the question that organizations specifying the standards, such as Continua Health Alliance, need to investigate is whether they are conscious of the risks they take when selecting a specific standard.

References:
[1] Nick Hunn, "Essentials of Short Range Wireless", Cambridge University Press, 8 Jul.2010

Regulations and barriers to new entrants.

Electronic wireless sensors could cut medical costs and everyone in the eHealth industry seems to think that this sector is ready to take off. According to a Juniper Research's recent report , the eHealth sector will enable a market growth with estimated sales of around $ 4 billion per year by 2014. The importance of this market can be seen everywhere in our life; networks operators are developing eHealth divisions while the improvement of eHealth applications for smartphones continues to increase exponentially.

If we can make this work the benefits will be infinite and it will finally lead to the disruption from an old and less technologic healthcare system. The eHealth system has all the features to be the next technological revolution, with the added benefit of saving our healthcare system form an already degenerated situation. A possible solution to the terminal meltdown of the health system is offered by Clayton Christensen in his book the Innovator’s Prescription, where he advises that “ the only way to effect a major change in healthcare is through the introduction of new, parallel business models to challenge those that our current healthcare structure is built on”.
Introducing new parallel business models means that new technologies will be needed for a more efficient and targeted diagnosis, as well as devices for monitoring and data exchanges that promote personal involvement of patients by making available personal health records. Clearly, this sounds familiar when considering the areas being targeted by Continua Alliance and by the eHealth society. Nevertheless, it is not simple to implement personal eHealth by developing parallel business models in opposition to the classical model, and there is a real problem in the regulations horizon, that can indeed put to an end the eHealth adventure. This “problem” is called FDA or Food and Drug Administration, which is an agency of the United States responsible for promoting and preserving the public health through a regulation process.

This means that the FDA has the possibility to apply regulations that will suffocate the development of eHealth. What is worrying is that by being a regulator, the FDA moves slowly when comparing it to the growing eHealth technology sector. The scenario is formed then by two parts; one part is the emerging eHealth market ready to develop, and the other one is a regulator structure that can reset the levels of expectations foe eHealth. The FDA programs for safety regulations have impact only in the U.S, which means that the eHealth expansion can only evolve outside the country, thus leading to a major disruption. It’s important for the manufacturers to understand the barriers of regulation and for the industry to engage with it to reform the levels of regulation for the eHealth system.

However, it is important to evidence that apart from slowing down the regulatory process, the FDA is also contributing to important improvements in the medical and fitness applications. More specifically, the U.S. Food and Drug Administration (FDA) and other medical bodies are concerned about the potential EMI generated by wireless connectivity medical devices. Over the years, many incidents of suspected electromagnetic interference (EMI) with medical devices have been documented [1]. Examples of the problems that could occur when radiated electromagnetic (EM) energy interacts with the sensitive electronics incorporated into many medical devices, can be seen when a ventilator suddenly changes its breath rate or when an apnea monitor fails to alarm. The key to addressing EMI is the identification that it involves not only the device itself but also the environment in which it is used, and anything that may come into that environment. The FDA states, “Wireless coexistence and data latency remain concerns because the data transfer rate can slow slightly or even dramatically with an increase in the number of similar transmitters in a given location. In many cases it is essential that medical data, including real-time waveforms and critical control signals and alarms, be transmitted and received without error” [2]. The Bluetooth low energy radios broadcast in the notoriously crowded 2.4 GHz band and it can be seen as the wireless technology that satisfy these conditions. That said, Bluetooth low energy operates at 1 mW (0 dBm) output power and only transmits for 1% (or less) of the time and then only in short bursts lasting a few hundred microseconds. Most modern medical devices have been created with a high degree of EMI immunity and the probability of malfunction in the presence of a short duration transmission is very low.

Typical Electromagnetic Environment for medical devices.

Licensing bodies such as the Federal Communications Commission (FCC) have attempted to mitigate the effects of EMI by restricting the power output of radio devices operating in the license-free parts of the radio spectrum to limit the possible EMI with sensitive electronics. Operating in the 2.4 GHz band is a major challenge with consequences for product design. More importantly, in order to ensure that communications are not disrupted, medical wireless monitors need a high level of immunity from other radio sources. To achieve this, Bluetooth low energy employs a frequency-hopping spread spectrum interference avoidance scheme. When making an initial connection, the two transceivers transmit using one of three fixed channels (trying the other two in turn if no signal is received) in order to establish the link. This is a faster and more power-efficient method of searching for a compatible radio source compared to scanning the whole band. If a clash occurs, the Bluetooth low energy transceivers switch to another channel in few milliseconds and report the corrupted channel so it is not used again. Even if the Bluetooth low energy technology seems to respond to the required features for interference avoidance, medical devices manufacturers would have to embark on a program of testing to ensure their products meet the electromagnetic compatibility requirements of the medical authorities. As new wireless medical systems have progressed to the consumer, one can easily think that by extending the sphere of influence of regulations structures, the quality, interoperability and adaptability of these devices is granted. In this scenario, the Continua Health Alliance is helping the FDA to understand the implications of eHealth, but this message is not influencing much of the industry involved. On the other hand, the situation is even more worsened by the regulatory consultants and legal firms that are more frequently evidencing the dangers that may exist within the actual regulation. The consequence is that the image of regulators as tyrants who interfere with the evolution of technology, is reinforced. Clearly the sphere of influence of the FDA’s agency is so wide that itself can regulate any device or application with a medical purpose. During March 2010, MobiHealthNews broke the story of the FDA’s removal of MIMvista’s radiology imaging iPhone app from Apple’s AppStore just months after the iPhone’s app marketplace opened. Since that, MIM’s application has been denied and is now in the process of filing a premarket approval. As with all regulation, the FDA helps to maintain the status quo, not least by providing a barrier to new entrants. However, in the actual health system where disruption and change is essential for the industry, that repulsion to new entrants threatens to deteriorate a possible change. At this point, we can say that if personal healthcare is to move forward then what we need is less rather than more regulation; the regulators can be seen as reason of delay instead of promoters of innovation for the eHealth sector. Indeed, regulators will hate the disruption that eHealth is generating in the healthcare scenario, not only because by creating a direct contact with the medical institutions and manufacturers it will possibly remove some of their powers, but also because new market entrants, who are far away from being part of the already established medical system will try to tell them how to work and regulate the emerging wireless technologies. In order to achieve innovation it’s essential to persuade manufacturers outside the medical regulations world, to join the health sector and help put pressure on the regulators while on the other hand we need to warn new manufacturers of the potential issues related with regulation. Continua Health Alliance as an open industry group is supporting as many companies as possible to enter the market. What is happening in the healthcare sector today, is that new companies that are thinking about entering the healthcare market hesitate to do so creating thus, a process that only makes slower and more complicated to lobby for regulatory issues. However, without any proof of support from the FDA, repeating the limits imposed by regulators will only worry the new entrants to access the market, or at least the US market, stopping investment and innovation. It is, of course more difficult to move the regulators towards the market demand, but what is certain until now, is that the wireless industries can really contribute to the development of eHealth, since their business structure is based on a user centric model as much as eHealth is based on being a patient centric model. If we want the eHealth market to develop further, it is essential to remove the possible barriers that regulators can impose and to achieve this health revolution we need to encourage as many companies as possible to invest in this adventure. This process can be slow and can be difficult, but if we keep on stressing the limits imposed, we may never capture the interest of the majority, which may expose to danger the whole future of eHealth.

References: 
[1] Silberberg J. L., Performance Degradation of Electronic Medical Devices Due to Electromagnetic Interference, Compliance Engineering (Fall 1993) pages 25-39
[2]  U.S. Food and Drug Administration. Draft guidance for industry and FDA staff: radio-frequency wireless technology in medical devices. http://www.fda.gov/MedicalDevices/DeviceRegulationandGuidance/GuidanceDocuments/ucm077210.htm#4        

The Standardization Process with Continua Alliance.

The personal telehealth system has the potential to cope with today’s major challenge and as any complex domain it consists of various levels of specifications. These various levels vary from the very concrete, for example WSDL interface definitions, to the abstract, for example the information structures, and each of these levels should be significantly dependent on each other. Now we can understand what kind of problem we have to deal with. As a starting point, a good assumption can be to think that we should relay on official standards bodies to standardize the wireless oriented health. So it would seem that creating standards for eHealth should not be that difficult. Is this assumption realistic? Not very realistic, we should say. Today, the entire eHealth sector is slowly progressing, but is still paralyzed by the national eHealth programmes. The principal problem is the national programmes need a system of uniform standards, while what they get is only a confusing and incoherent output. In my previous blog post, I have already mentioned the relevant contribute that Continua Health Alliance is having in the ecosystem of eHealth standardization. Continua Health Alliance is the only group of technology, healthcare and fitness that is succeeding in creating an ecosystem of connected personal health. According to Continua’s mission “establish a system of interoperable personal telehealth solutions that fosters independence and empowers people and organizations to better manage health and wellness”, the alliance formed by more than 220 company members around the world, plans to select connectivity standards and set guidelines for the desired interoperability. A good question that comes to my mind is to investigate if Continua Alliance isn’t just another standards body and why is this alliance different from the others. Continua is not a standards body, since the objective is not to develop new standards but to adapt or modify existing ones as much as possible. Alongside with leveraging the existing standards, also guidelines are considered essential by this open industry organization, in order to identify and resolve gaps in some standards bodies so that interoperability is improved in the eHealth system. More specifically, the Alliance is writing these guidelines for understanding how to use standards to achieve true interoperability across a variety of devices all oriented to personal telehealth. The core role of Continua is not always easy to understand. When the eHealth system was starting to appear, Continua was created as a non-profit, open industry organization to provide guidelines for the health ecosystem. If we simply analyze what this alliance is doing in the health sector, we can superficially assume that its key function is to ensure that devices from different manufacturers are compatible. Wrong assumption, because this is just a consequence of what Continua is doing in the standardization process. Its real effort is to ensure the integrity of the data flow from the measuring system to the electronic health record, which is the last component of the entire process. If we consider a typical eHealth structure, what is requested for the medics consulting a health record is to have accurate and reliable information that can flow automatically in the records. In the wireless world not always the data exchanged is not corrupted and secure. Whenever a data is flowing over an electronic link, especially if we consider a wireless link, it can be transformed and during the conversion process it might be converted to different units or manipulated in a variety of ways. This means that when the piece of data is finally ready to get to the final stage, it may have undergone to a set of manipulated data that can entirely corrupt the entire process. Therefore, we can finally understand the importance of Continua and why it is dramatically affecting the standardization process: the goal of the Continua Alliance is to provide a certification ensuring that if each stage of the process is conformed to their guidelines, then the received data will not be corrupted from that generated by a piece of medical equipment. Here comes the creation of the Continua logo, meaning that the path from the medical instrument to the medical health record is secure and that products are expected to work together. In addition, the Continua certification imposes a rigorous testing of products by independent test organizations. Of course, publishing and defining a standard is not enough to ensure a correct data flow and interoperability; this is why Countinua is very oriented towards logo certification and testing in a rigorous testing environment. As we saw previously, when the Bluetooth low energy approached the ICT market, the idea of using it for eHealth solutions didn’t take so long to become real, and obviously Continua has selected the Bluetooth Low energy in the guidelines. The testing procedure for certain standards has to follow a certain pre-decided procedure, generally selected by the standardization body. Due to the importance and diffusion of the Bluetooth technology, the Bluetooth SIG organization decided to invest millions of dollars in interoperability testing, thus making sure that once in the market its adoption was fast and diffused.
On the technical side Continua has decided to adopt a backward compatibility point of view, to ensure that devices supported by different versions of the guidelines are interoperable. At the same time regulatory changes and new reimbursement models are still studied and accepted.

Regarding the architectural structure of personal eHealth systems, Continua has the role of defining interoperable interfaces for the whole structure starting from the medical device at the patient’s home to the medical health records services. Since the beginning of its adventure, Continua selected a variety of wireless standards for the connection of medical devices to the system, including Bluetooth, USB, ZigBee amongst others; time has shown us that BL LE or Bluetooth more generally, is the selected technology for its robustness, data integrity and interoperability. In addition, for connections regarding the patient’s home to the back-end services some candidates are Cable, GPRS or CDMA, WiMax and DSL. Besides the technical aspects, the alliance plans to collaborate with the regulatory agencies of the government, such as FDA, regarding policies for the use of personal health wireless devices at home. This is the contribution of the Continua Health Alliance to the standardization process and it is a step forward in the right direction.

The Continua Health Alliance organizational structure.

Since Continua was formed, the market of smartphones and applications for health and fitness care has incredibly blossomed. Continua’s vision of end to end secure data flow remains stable through the years and the technological advancements, but how will it embrace the consumer health with the use of mobile phones is still not clear. I mentioned before the importance of the Continua certification logo; now, Continua has the complicated problem of deciding what their logo means when present in a medical device. If a consumer decides to buy a wireless health device with their logo, it means that the standard of end-to-end integrity is assured or that it is a device that connects to any consumer medical application? The boundaries between these two situations are not very defined, but what is sure is that the product bearing the mark has successfully met the certifications requirements, thus is ready to be used in the eHealth system. What is important in the standardization process, not mentioning for a second the wireless technology and compatibility issues, is that Continua’s major achievement was to stimulate partners from a diverse range of industry to come together for the commune cause of eHealth development. Even more, they have formed a regulatory group, which is discussing these issues with the powerful FDA and with other regulators around the world. This is the process necessary if we want to see evolution and standardization take place in the eHealth system.

If Everything is SMART then the Bluetooth is Smart?

This year has been full of innovations in terms of devices evolution, wireless technology applications and mainly it’s been a remarkable year for the diffusion of the Bluetooth 4.0 wireless technology; this time, also the eHealth sector was deeply affected by the new technology applications.
In March 2012, Continua’s new Design Guidelines ('Catalyst' 2012) [2] were already available to Continua’s members. Continua's 2012 Design Guidelines introduces for the first time products that include the Bluetooth Smart technology, based on the Bluetooth v4.0 specifications. Currently this new version of Design Guidelines is under interoperability testing and will be officially released by the end of this year for free. Bluetooth Smart is a new variety of Bluetooth v4.0 peripherals, thus, mainly sensors devices used in eHealth such as blood-glucose meters that are designed on small batteries. The Bluetooth Smart devices include a single Bluetooth v4.0 radio that will connect only to Bluetooth Smart Ready devices.

According to the IMS research latest report, “Wireless Opportunities in Health and Wellness Monitoring – 2012 Edition,” Bluetooth Smart will be the dominant wireless technology for medical devices by 2016, even if today only 5% of the medical devices have a wireless connection. In addition IMS research estimates that more than 50 million wireless health monitoring devices will be used during the next five years. With the constant expansion of the Bluetooth wireless technology we all know that we can easily connect different devices together, but we need firstly to understand which devices can really work together. For example we should know if our watch can send information to the IPad or if our IPhone can communicate with the TV. Here comes the idea of developing the new Bluetooth Smart: if a device has the Smart logo then you will easily be able to define compatibility. More in specific, the Bluetooth Smart devices are implemented in such a way that, if you want for example to know how much you weight today, or better if you want to have information about your glucose level, the Smart devices collect the specific part of data that is relevant for the required information and then send it to a Bluetooth Smart device. Bluetooth Smart devices gather medical data and then transfer the information to a Bluetooth Smart Ready device such as TVs, tablet, phone and even game consoles. Once these data are collected by the Bluetooth Smart Ready devices, the consumer can put to work the data using a WiFi connection to a cloud platform such as Microsoft Health Vault Platform where the a healthcare system can monitor them. One of the biggest advantages of the Bluetooth Smart Ready devices is that by using a dual-mode radios it is possible to efficiently receive data from both the Classic Bluetooth and the Bluetooth Smart Devices and in addition a Smart Ready device allow the software to be updated by the consumer in order to enhance compatibility with a variety of products. In contrast The Bluetooth Smart devices include a single Bluetooth 4.0 radio that will connect only to Bluetooth Smart Ready, having only a single mode low energy radio. This means that a typical Bluetooth Smart device is an exception in the Bluetooth “family” because it can connect only with Bluetooth Smart Ready devices and Bluetooth devices explicitly mentioned by the manufacturer. Now a question I have since I read about the Smart technology is how are related the Bluetooth Low Energy and the Bluetooth Smart? If the Bluetooth Smart is just slightly different from the Bluetooth 4.0, then why not call it simply Bluetooth? Bluetooth Smart is a new definition for Bluetooth Low Energy devices. As we saw previously, Bluetooth low energy is based on extremely low energy devices, those that run on button-cell batteries for several months and even years. So, once you have a wireless connected device with these features, it is a direct consequence that it will encourage the development of other advanced Bluetooth devices, and Bluetooth Smart devices in particular. Here comes the problem and the solution at the same time: allowing small devices to establish ultra low power wireless connection means also a better need to understand what devices work together. The Bluetooth Smart technology is the solution and the first step to ensuring compatibility of all the Bluetooth devices. The ultra low power consumption is the key feature to be considered when choosing Bluetooth profile for healthcare. A possible contender to the Bluetooth technology can be seen when analyzing alternative ultra low power technology such as ANT+. Precisely, ANT+ is a wireless standard connectivity that provides a low power solution for short range wireless communication for automatic transfer of medical data, that can be a possible alternative to the Bluetooth technology, but the fact that consumers and companies offering chips are way more familiar with the Bluetooth technology than with ANT+ indicates already who is going to be the winner.

References:
[1] http://imsresearch.com/press-release/Consumers_Not_Telehealth_Patients_to_Drive_Adoption_of_Wireless_Technology_in_Medical_Devices
[2] http://www.prnewswire.com/news-releases/continua-health-alliance-design-guidelines-now-available-free-to-developers-reducing-development-costs-for-plug-n-play-personal-health-solutions-147148915.html

Bluetooth Low Energy Features and coin cells

Bluetooth low energy (BLE) technology is the key feature of the Bluetooth Core Specification 4.0 (Bluetooth v4.0) and it is one of the latest technology to incorporate a very low power, relatively short range (50m) features [1] while using for communication a coin cell battery that can last almost two years. It has inherited several technical features from Classic Bluetooth technology, since it is a further evolution of it, thus provides power efficiency, excellent resistance to interference, small size and scalability. The key features of Bluetooth Low Energy can be summarized as follows:

• Ultra-low power consumption

• Ability to operate for long periods (months or even years) from a coin-cell batteries

• Low cost due to the already existing Bluetooth ecosystem

• Interoperability

• Robustness and Reliability

Bluetooth Low Energy has features similar to those of the Classic Bluetooth technology but in some ways, BLE technology is a very innovative wireless technology including new features such as proximity sensing and a variable connection interval up to few millisecond to transmit small amounts of data instead of the Classic Bluetooth fixed connection interval for periodic high activity connections. Similarly to the Classic Bluetooth, BLE uses Adaptive Frequency Hopping (AFH) spread spectrum for accessing to the shared channel, in order to have a robust transmission against the possible noise in RF environments such as medical environments or generic buildings. AFH also decrease interference probability from Bluetooth technology to other wireless technologies in the same radio space, since Bluetooth technology, IEEE 802.15.4/ZigBee ,Wireless LAN, use the license-free 2.4GHz Industrial Scientific Medical (ISM) band. However, since the priority of the BLE technology is to reduce energy consumption, the number of hops was reduced to 40 and the channel width is 2MHZ [2] as opposed to the Classic Bluetooth technology where the number of hops was 79 and the channel width was 1 MHz.

Bluetooth  low energy channels

Bluetooth Low Energy can operate either in a master or slave role, but never both; there is no scatternet topology for Bluetooth low energy technology. BLE has a star topology; a master can command multiple simultaneous connections with a number of slave devices controlling also how often the slaves are allowed to communicate, but a slave can only be connected to a single master communicating by request from the master. A relevant feature that can be seen when comparing the BLE with the Classic Bluetooth technology is the “advertising” functionality. In a BLE discovery is done so that a device acting as a slave advertises on one or several advertisement channels that it has something to transmit to the master. Then the devices acting as masters scan these channels in order to find possible slaves. Once there is a discovery, transmission messages can also include connection events in which the master and the slave wake up in synchrony for exchanging frames.
The ultra low power consumption and coin cell battery operations use also has it own limitations. The ultra Low power BLE technology has an average current consumption of less than 1 mA; this assures there is no overlap since a ultra low power standard can still work in this range if the data throughput is low, since transfer rates for BLE technology are below 100 kbps. This means that some applications works better with the Bluetooth Low Energy connection than others. The simple lithium coin cells batteries, also used for watches for example, have been selected for the BLE wireless applications, but in order to be able to function with a good battery lifetime some important improvements are necessary.The battery lifetime used in a typical ultra low power standard [3], is dependent on the battery capacity and the average current consumption. Therefore while working with ultra low power consumption it is not only important to focus on the average current consumption that should obviously be as low as possible, but it is also necessary to consider that unlike traditional coin cell applications, wireless applications battery capacity is not fixed and is dependent on the various usage pattern.When considering coin cell battery for ultra low power wireless operations to maximize the battery lifetime  it is important to select devices with the lowest peak current for minimizing the current drain; the low peak current is the main  reason why the coin cell battery is very suited to Bluetooth Low Energy applications. 

When talking about BLE technology, is it almost obvious form the definition and from the name itself that it consumes very little energy, but going through a more technological overview the truth is that, indeed this technology is low powered but there are some applications for which the BLE technology is not sufficiently low. In order to have low power consumption different solutions can be applied. For instance, a good approach can be to modify the way the radio operates. If the radio is switched “on” only when it has data to send for a very short period and then after sending data returns to its sleep mode, then the power consumption will be absolutely reduced. On the other side, with this type of solution, also transmitting and receiving times are quick and the connection is rapid and a “not connected” state is enabled. When the “not connected” state is used then the devices at the two ends are aware of each other but only connect when needed and for a very short time. 
In this case, the two ends of a link are aware of each other, but only link up when absolutely necessary and, even then, it’s for as short a time as possible.
There are other ways Bluetooth low-energy technology can control the energy efficiency. A good solution is to allow more packets to be sent within a connection event and by implementing AFH to avoid interference. In addition it is possible to reduce the low power consumption by sending very short packets; Bluetooth low-energy technology uses a modulation index of 0.5 for the Gaussian frequency-shift-keying (GFSK) modulation which is close to a Gaussian minimum-shift-keying (GMSK) scheme thus, lowers the radio’s power requirements. Moreover, lower modulation index does generate a couple of beneficial side effects: increased range and enhanced robustness.
When considering BLE technology, it is interesting to understand how it is implemented in tablets, mobile phones or health care centres. The Bluetooth devices are connected to a web based application where it can share its radio and can be considered thus, as a conventional Bluetooth Health Device Profile (HDP) and a BLE controller with the advantage of having very little additional circuital parts required in the chips, making this technology ideal for low power home and hospital medical applications.



References:
[1] C. Sorrel, “Casio Bluetooth low energy watch has two year battery life: http://www.wired.com/gadgetlab/2011/03/casio-bluetooth-low-energy-watch-has-two-year-battery-life/,” Wired magazine, Mar. 2011.
[2] http://www.connectblue.com/press/articles/bluetooth-low-energy-technology-and-healthcare/
[3] http://www.eetimes.com/ContentEETimes/Documents/Schweber/C0924/C0924post.pdf