Healthcare Wireless and Device Connectivity

WLAN Convergence on a DAS and IEC 80001

Medical devices of which includes infusion pumps and patient monitoring and also other monitoring modalities as pulse oximetry, are in an increasing fashion moving their applications across the WLAN (Wireless LAN).  As a result of this there will be an increasing need to develop the correct deployment model to scale the x number of medical wireless enabled devices (no matter the bandwidth); and further how they will establish the correct QoS, and also to exist within the right quality of service (QoS) for all applications. Also has to be factored into how these life critical applications will exist with other needed data and voice requirements on the WLAN, i.e. quality of service, as stated.

All medical device manufactures with WLAN client adapters do have to be tested and validated not only the described quality of service or should; but have to submit their testing data to internal regulatory, and finally pass muster with entire FDA process.  This testing and design process of the WLAN has been based upon the well established and proven micro-cellular or proven (WLAN) architecture.  Many of these medical device companies have relied upon www.veriwave.com as Veriwave is the gold standard in the industry for this type of testing  Oh yes, the majority of WLAN companies use Veriwave for testing their internal radio designs.

Their seems to be discussions regarding the use model of these regulated WLAN devices that were validated on a industry best of designs for the WLAN industry to be utilized in a DAS infrastructure (Distributed Antenna System) architecture.

Several caveats need to potentially looked at or evaluated.

• Will the end hospital client or infrastructure provider assume the risk for the deviation from the approved and regulated model, that is the micro-cellular architecture (WLAN)?
• How will this infrastructure impact the proven quality of service model, and how acceptable will this be the the end user?
•  What is the overall initial cost and total cost of ownership to go against a proven industry standard micro-cellular architecture (WLAN) of those companies that control a plus 85% of the WLAN industry?
• End users should get several quotes of which includes a converged design, a stand alone WLAN cost model, and a stand alone DAS model.  They will be surprised at the cost deltas regarding a converged model, that is WLAN with a DAS.
• If the end client or infrastructure provider decides to drive this model, they should assume the costs of the additional infrastructure and any changes going forward, and yes what risks are involved?
•  Finally, one has to ask themselves how a DAS will ever support 802.11n or MIMO, and what implications this has for cost of changes of DAS infrastructures that were originally designed for 802.11a/b/g. Not that medical devices are incorporting 802.11n now, but this is the natural migration.
• DAS designs are normally non-diversity, so how will this impact the S/N (signal to noise ratio) or help negate multi-path occurences that can be overcome with a diversity or MIMO micro-cellular infrastructure.

See of which is attached a most excellent article touching on several of the aforementioned topics by Dr. Steve Baker. Steve and I have authored an article before and I consider him one of; if not the most respected authority on challenging the correct use model of medical devices in the WLAN industry.

 

Download Wimd2225-baker1_authors_version
 

802.11n MIMO is the threshold reached with convergence on a DAS?

While I have never been an advocate of overlaying WLAN on a DAS, in theory and some practice this could be done with 802.11/b/g and even (a); however everything comes with a price.  Engineering to -85dB for data for 802.11a/g, while not diversity  this may or could be done. Adding capabilities for voice (voice over IP), and you have another dimension such as an increased signal strength requirement of -65dBm. Then when you add 802.11a, amplification of the signal is needed either at the antenna element or in the IDF (to meet the link budget.  DAS systems work well for what they were intended to do. That is transmitting broadband signals such as traditional cellular at 850MH and PCS at 1900MHz. At these frequencies you have a approximate coverage pattern of 10,780 sq. ft. per antena element. At the VHF or UHF range this dramatically increase to 34,375 sq. ft. However to to meet the link budget requirement when WLAN is combined on a DAS, this decreases coverage to 3,520 ft per antenna element.  Adjustments also have to made for 1/2" coaxial cable loss.  Going back to 850MHz and 1900MHz, you will have 2.5db of loss for every 100ft at 850MHz and 4.0 db of loss at 1900MHz.  At 5.750GHz, this loss increases dramatically to 8.0 db for every 100ft.  Now moving to 802.11n and the use of MIMO. The race is on between Verizon and LTE oer 700MHz and Sprint with WIMAX.  Not doubt LTE will probably take the edge because of Verizon's major footprint and the fact that a huge build-out is not required as required for WIMAX.  DAS companies tend to claim support of 802.11n because of the inherent portended support of MIMO for WIMAX. Again, the question begs to mind how the heck will this work?  Oh yes, and how much will this actually cost? Remember MIMO needs multiple antenna pathwyas (in and out x 2). If the AP(s) are in the IDF, will you need four independent runs of coaxial cable or do you extend the AP(s), out on the floor and then come up with a way to run ethernet over coaxial? MIMO should be preserved as it takes advantage of multi-path to increase throughput in theory up to 600MB/sec, realistically 300MB/sec. My suggstion for any enterprise customer that is looking for 802.11n and a DAS is pretty simple.  Get a DAS quote for all the broadband services, i.e. cellular, PCS, UHF/VHF, etc. Then get a quote for a discrete (stand alone), WLAN, i.e. 802.11a/b/g/n.  Then get a quote from the DAS supplier for broadband services and WLAN services (to include 802.11n). Compare pricing of all quotes two discrete systems versus combined. Finally get in writing as a part of the contract documents that 802.11n will be fully supported in all it's features and functionality. In addition, contact your WLAN provider of 802.11n, and obtain in writing that they have tested and that they approve the use of their specific 802.11n AP and controllers with a DAS.

 

Aruba Networks Web Event or WebinAir

This was the first web event held today with Integra Systems, Inc. content for Aruba Networks, inc. The content will be provided online in the next few days; but overall this was a resounding success. It was all about 802.11n, rightsizing the network and helping the healthcare delivery model or IDN save $$ on capital expenditures immediately; while looking long term to implement 802.11n and save additional CAPEX and large OPEX overall savings over the implementation life cycle care process. However, this could occur simply with the roll-out of 802.11b/g/a over the past several years. Up to it is estimated 30% of wired ethernet ports are simply not being used anymore. Not only could these ports be reduced, but a now rightsizing of the L2/L3 IDF. 802.11n throughput exceeds the wired desktop and the value of increased channels and MIMO combined with the QoS of what Aruba Networks provides, simply makes this bullet proof for data, voice, and medical applications.

Aruba Networks Web Event

While I wanted to post this a few weeks back; however international travel and realizing the personal value and the stress of of what is happening  day to day and hour to hour of special people in my life overcoming huge (no words can make this enough) events like pancreatic cancer took precedent. On the 21rst of this month, October (this forthcoming week) (will provide the links on Monday), the first ever healthcare web event event regarding "rightsizing" the wired and wireless network and the value proposition of 802.11n will be held by Aruba Networks  www.arubanetworks.com with approved content from Aruba Networks via Integra Systems, Inc. www.integrasystems.org  A lot of these type of events tend to spin into the technical, that is OK; as this where the healthcare space has played out before; but this will be different. This event will focus on the not only in a minor way the technical, but the financial and clinical differentiation via now the full approved/ratification of 802.11n (finally) on September 11, 2009. At the end of the day (no matter what the blessing is by standards), it is making and allowing the clinical care giver experience better,(decreasing the as I say, the "hassle factor") while ensuring the proper QoS, security, saving a lot of $$ to deploy and manage, while ensuring that this deployment strategy meets and exceeds that clinical requirements year ahead. However, also to keep in mind that each application will need to be looked at regarding the actual bandwidth requirements. That will become the important in our wireless and mobility model for our now and going forward thus changing healthcare delivery system via 2009 and beyond. Rightsizing the network via 802.11n will actually save $$ and deliver new practice models, never thought of before.   

Philips Medical Systems (IntelliVue) and Aruba Networks Press Release

This is to congratulate Philips Medical Systems www.philips.com for their recent press release with Aruba Networks.  http://www.arubanetworks.com/company/news/release.php?id=204   After over six years, finally the market leader in patient monitoring has somewhat now followed the trend and marketplace proven abilities of Welch Allyn and Draeger Medical Systems. It is the innovators that can change the direction of the industry it seems.  Please note the similiar press releases from Welch Allyn and Draeger Medical. http://www.welchallyn.com/pressroom/releases/pressNews.jsp?id=18-ca-114-1228142540757  http://www.encyclopedia.com/doc/1G1-177983584.html over a year and more ago. This seems to show that Philips Medical Systems as a medical device manufacturer of "portable" patient monitoring can "finally" converge their "portable IntelliVue" patient monitoring application with other enterprise data, voice, and video traffic. Previous it seemed there was resistance to to accomplish this by Philips, meaning the requirement of separate dedicated AP(s) for 802.11a.  No doubt a lot of resistence was encountered for multiple networks and dedicated AP(s), it just did not make economic sense and the technical argument lost steam. The fact that they partnered with Aruba Networks says a lot as Aruba provides the Quality of Service (QoS), on a packet to packet level basis that will provide the needed quality of service for such life critical applications and alarm persistence as patient monitoring. This is quite unique in the WLAN industry, and Aruba Networks has a patent on this.  Now that Philips is  going to market with this solution; what is the solution for WMTS from Philips Medical Systems?  Unlike both Welch Allyn and Draeger that have introduced “patient worn” (traditional telemetry), monitors in 802.11a/b/g, it seems that General Electric, and Philips will need to install a separate antenna infrastructure for WMTS.  So again, this means two separate antenna infrastructures.  Will Philips Medical Systems also be able to provide a VLAN based strategy for the "wired" hardwired network sharing existing L2/L3 switches, or will this require dedicated switches and a separate "hardwired" networking topology for IntelliVue? The trend in the growth of patient monitoring is in telemetry monitoring (patient worn monitoring), and the trend is for this to be house wide to provide flexible patient monitoring, not just traditional unit based telemetry. The logical next step for Philips will be (it seems it should) be a migration strategy from legacy WMTS to enterprise grade 802.11a/b/g/n patient worn (telemetry), monitoring and converge this onto a WLAN Aruba Network as well as provide as stated (aforementioned) portable (transport), patient monitoring. This could provide the healthcare industry huge cost savings, while additionally lowering risk for QoS and real time monitoring.  Cost savings include a one time site survey, coordinated installations, and real time SNMP monitoring  for security, IDS, and QoS using the enterprise AirWave tool from Aruba Networks. Note WMTS cannot  use enterprise grade tools since it is proprietary. So the final question remains, now that Philips it seems  has followed where the industry is going; how long will it be before they introduce to the market a replacement for IntelliVue WMTS?  Welch Allyn and Draeger Medical already have solutions at hand. That is an enterprise converged wired and wireless network (using existing L2/L3 switches, controllers, and AP infrstructure) that can handle both 802.11a/b/g portable monitoring, hard wired networks, AND "patient worn" traditional telemetry in 802.11a/b/g. This is nothing new for these companies as they have been doing it for years. The result has been a lot of cost savings for hospitals both from a CAPEX and OPEX.