This is a post-peer-review, pre-copyedit version of an article published in Journal of Medical Marketing. The definitive publisher-authenticated version "Konstantinos A. Banitsas, R.S.H. Istepanian, Sapal Tachakra. Applications of medical Wireless LAN systems (MedLAN). Journal of Medical Marketing, Volume 2, Number 2, 1 January 2002 , pp. 136-142(7)" is available online at: http://www.ingentaconnect.com/content/pal/jomm/2002/00000002/00000002/art00008.In this paper the Wireless LAN (WLAN) networking principals are presented along with some of the implementation scenarios dedicated for Accidents and Emergencies wards. Preliminary simulation results of the MedLAN concept are also presented together with ongoing and future work in this area

Banitsas, KA

Istepanian, RSH

Tachakra, S

English

Banitsas, K

Istepanian, R. S. H.

Tachkara, S

Kingston University Research Repository

Applications of medical Wireless LAN systems

Brunel University Research Archive

Applications of Medical Wireless LAN Systems (MedLAN)Konstantinos A. Banitsas*, R.S.H. Istepanian*, Sapal Tachakra*** E-MED systems and Health Engineering Research GroupDepartment of Electronic & Computer Engineering, Brunel University, Uxbridge, UB8 3PH, UK[robert.istepanian@brunel.ac.uk], [bany@hol.gr], www.bany.grwww.brunel.ac.uk/departments/ee/Research_Programme/e_med/pages/index.htm** A&E Department, North West London Hospitals NHS Trust, Central Middlesex Hospital, Acton Lane,London NW10 7NS. [sapal.tachakra@tinyworld.co.uk]ABSTRACTIn this paper the Wireless LAN (WLAN) networking principals are presented along with some of theimplementation scenarios dedicated for Accidents and Emergencies wards. Preliminary simulation results ofthe MedLAN concept are also presented together with ongoing and future work in this area.Keywords: Telemedicine, WLAN, IEEE802.11b, telecare, Hiperlan/2, IEEE1394INTRODUCTIONThe applications of emerging wireless technologies for medical environments is a new and evolving area oftelemedicine that exploits the recent developments in mobile networks for telemedical applications in general[1], [2].The aim of this paper is to present the main design and development elements of an integrated mobileWLAN system dedicated to accident and emergency wards and describe the anticipated challenges from boththe telemedical and telecommunications point of view.In typical medical scenarios, WLANs represent a practical and highly flexible way of transmitting data. Thiscan be attributed for the following reasons:· Older hospital structures and buildings are not suitable for cabling and wired LAN applications, withcost effective installations.· Mobility issues, where staff on the move can access their patients from different access points incomplete roaming capabilities.· Installation flexibility as the network can reach places the wire can not.· Scalability, as the network can be configured to various topologies to suit the changing needs of ahospital· A wireless LAN can work as an independent network, as well as in conjunction with an already existingLAN [Fig. 2]WIRELESS LANs STANDARDS AND NETWORK TOPOLOGIESThere are four main wireless LAN standards ranging from the already established IEEE802.11 to the verynew and still unstandardised Hiperlan/2.Table 1 presents an overview of the four most well known wireless LAN technologies along with their basiccommunication characteristics. [3]IEEE 802.11a IEEE 802.11b Hiperlan1 Hiperlan2Frequency band 5GHz 2.4GHz 5GHz 5GHzLicense (ISM) No (Not applicablein Europe)No No No (not applicablein Japan)Frequencies 5.15-5.30 & 5.47-5.725 (Non-Europe)12 channels2.4-2.483 GHz, 3non overlappingchannels5.15-5.30 GHz5 channels5.15-5.30 & 5.47-5.725 (Europe)Max capacity 20Mbps 11Mbps 20 Mbps 54MbpsIntermediate speeds 6, 9, 12, 18, 24Mbps1, 2, 5.5, 11 Mbps 6, 12, 24 Mbps 6, 9, 12, 18, 27,36, 54 MbpsModulation BPSK, QPSK,16QAM, 64QAMDBPSK, DQPSK,CCKGMSK BPSK, QPSK,16QAM, 64QAMMAC Ethernet based Ethernet based Ethernet based ATM basedTypical Power 25mW 30mW 0.1-1W 25mWQoS Low Low Medium HighPossible Interference Satellite com (notfor openenvironments)Microwave ovens,cordless phones,Bluetooth,fluorescent lampsSatellite com (notfor openenvironments)Satellite comTypes of applications WLAN, real-time WLAN, real-time WLAN WLAN, video,broadcast, MPEGTypical radius 20-100m 30-200m 20-100m 20-100mCost today Low Low Medium HighNumber of applications today Medium High Low LowTable 1. Comparison of WLAN standards and technologiesA brief discussion of these standards is given here for completeness:· IEEE802.11a is mainly used in the US. It is a protocol capable of transmitting up to 24Mbps of data(with some being used to control the traffic), using the 5GHz band.· IEEE802.11b is the former protocol’s equivalent to the European market. Its speed is limited to 11Mbps,as it uses the 2.4GHz band, but there are products on the way, that will increase its speed to 20Mbps.Plenty of devices are available to the market, supporting this protocol that is the European standardnowadays.· Hiperlan/1 was established by the ETSI at 1996. Using the same band as IEEE802.11a, it providessimilar characteristics.· Hiperlan/2 is the new protocol that promises high data rates with unparalleled QoS, suitable fortelemedical applications. Specifications and working parameters of this standard are currently underdevelopment. [4]MedLAN: SYSTEM DESIGN AND MODELLING ISSUESThe current system’s design and research methodology is divided into three main tasks representing thepyramid development procedures of such application:· Modelling and simulation studies to define the biomedical digital signal processing requirements forinternetworking operational modes with 2G and 3G mobile systems [2], [3], [Fig. 4]· System hardware and software design to implement a mobile MedLAN system capable of transmittingseveral channels of medical data and information· Clinical testing and evaluation of the prototype MedLAN model, radio link and data acquisition server.Fig. 1. Schematic of the MedLAN systemA schematic of the MedLAN system, is shown in Fig. 1. It consists of the two main parts: The mobile trolleythat exists in the Accident & Emergencies ward (A&E) and the consultation point, within the hospital.The mobile trolley consists of a high performance laptop computer that is equipped with a WLAN PCMCIAcard (initially using the IEEE802.11b protocol) that will permit total mobility within the A&E room andbeyond. An access point within the A&E room, acts as a transiver for the network data to be transmitted toand received from the rest of the network structure. A high quality digital camcorder is connected to thelaptop and with the use of the IEEE1394 protocol, high-resolution video and audio is transmitted. Additionalmedical instruments (like otoscopes, dermascopes etc) are also connected to the laptop providing a low-weight compact roaming system. It is expected that the weight of the contents of the mobile trolley wouldnot exceed 4 kg. Fig. 2. Connection network topology of the MedLAN systemIn the consultation point (that can be at any location within the hospital) the consulting physician can have achoice of teleconferencing either from a fixed computer within the existing hospital network, or a mobilelaptop, sharing the same mobility advantages as the former laptop. It will even be capable of transmittingvideo to a PDA pocketsize computer [Fig. 2], thus taking advantage of the recent developments in PDAs.This way (and by placing additional access points to the general area where the consulting doctor would be),the doctor can move around the area while only carrying a 200 gr PDA. The PDA will be equipped with aPCMCIA card and it would be able just to receive video.A simple block diagram of the system is presented in Fig. 3. It displays the two main areas (A&E ward andConsultation point), along with the basic components of the system.Fig. 3. A simple block diagram of the MedLAN systemDigitalCamcorderMicrophone SpeakersLaptop PCMCIAWLAN cardOtospcope Dermascope MedicalinstrumentsA&E Ward, (mobile trolley) Consultation pointAccesspointEthernetbridgeDesktop Laptop Palmtop PrinterFibre opticsDSLISDNWLANIEEE1394For the modelling purposes of this project, OPNET Modeler 7.0 was chosen. This software package includesa radio library that permits simulation of Wireless networks.Fig. 4. MedLAN model using OPNET ModelerFig. 4 shows the model created. It consists of a wireless node (mobile_node_0) that represents the laptopcomputer that roams around the A&E ward, an access point that will probably be placed in the centre of theceiling of the A&E ward (wireless), a fast switch responsible for distributing the data (switch) and a desktopcomputer (node_0) that will be placed in the consultant’s office. All the possible applications that the unitscan use, are stored within “App Config” while the settings for the applications that were used in this specificmodel, are within “Profile Config”. Overall, the modelling of the system produced encouraging results,proving the feasibility of the MedLAN project.DISCUSSIONThe work is currently ongoing on the implementation of the system in a typical West London hospital:Central Middlesex Hospital, Accidents & Emergencies ward.Although there are numerous possibilities about the use of WLAN in such environments, applications can besummarised as follows:· Rescue services to main base A&E Department.Rescue services like the fire-brigade go to main A&E departments so that there is no delay in the extricationof casualties. It would be useful to transfer image and conversation from the accident scene to the basehospital. An example would be for a doctor to authorise a simple removal of the casualty from the carthrough the door, instead of cutting off the roof. The time is bound to come when drugs and therapy will bedelivered in the home, instead of going through the delay of bringing the patient to the hospital.· Point of care clinical protocols or medical informationSome doctors and nurses already use PDAs for this purpose but the use becomes restricted because of thelimitation of storage capacity on a PDA, so it is easier to link a notebook or a PDA through WLAN to acentral resource. This removes the need for the doctor to move to a fixed computer point to access suchinformation.· Inventory checks and maintenance schedulesThese involve data entry on pieces of paper and subsequent tallying, much of which can be streamlined as insupermarkets.· Medical availabilityDoctors now aspire to a leisure-orientated time-restricted lifestyle but they would like to be available from avariety of locations. The use of notebooks, sub-notebooks or PDAs would be a perfect way of maintainingthat contact with their peers or base.· Virtual hospital bedAlthough we envisage that in the future this will be a reality, there will remain an application of WLAN forlow dependency areas in the short term with WLAN devices on carts with option of addition of peripheralslike otoscopes, opthalmoscope, etc for enhancement of the ability to establish a diagnosis.· Patient transfersAt the moment transfers from one part of the hospital to another can be so bureaucratic and so fraught withloss of information, current state of the patient etc, that it would be easier to transfer a WLAN device totransmit patient information, images etc.· Multi-professional educationEmergency medicine is one area in which there have been significant advances in teaching nurses to performdoctors’ work. This has brought the need of multi-professional education to the fore. Currently there aredifficulties of scheduling doctors’ and nurses’ study time together, but it is easy to envisage that in the futurea group of hospitals would band together to achieve this and still leave enough persons on the shop floor.Another important aspect of this research in this area will be the design of a system that remains compatiblewith future developments in mobile radio networks. This is particularly important considering the speed ofthe progress that the wireless products have experienced over the last few years.The future promises new wireless devices (that will adopt the Bluetooth protocol), higher bandwidth (afterthe final release and commercialisation of Hiperlan/2) and smaller and more convenient PDAs that willeventually replace laptop computers in telemedicine scenarios.HiperLAN/2 is increasingly getting the interest of the engineering community. With its official release, itwill offer much higher bandwidth (up to 54 Mbps), but most importantly, Quality of Service (QoS); afunction that is missing from today’s protocols [Table 1]. This way, the user will be able to select tasks thatare more important than others, thus decreasing the fluctuation that the network suffers from and offer higherbandwidth to the real time applications. Additionally, HiperLAN/2 will internally support IEEE1394protocol that MedLAN uses for video transfer, and will lead to the elimination of the protocol conversionsand the increase of the video quality. Finally and most importantly, HiperLAN/2 will act as a bridge betweenWLANs and UMTS thus being able to transmit video in any cellphone, anywhere in the world.CONCLUSIONSThis paper presents the design concepts of MedLAN system dedicated to a wireless networking system inA&E hospital wards. This system demonstrates a new and emerging type of mobile telemedical services andattempts to show that there are important benefits of exploiting the emerging wireless LAN technologies inhospital environments.The preliminary modelling results has shown that the MedLAN network can provide a working system intypical A&E wireless traffic scenarios, with acceptable performance.REFERENCES[1] Istepanian RSH, and Laxminaryan, S, UNWIRED, The next generation of Wireless and InternetableTelemedicine Systems. Editorial Paper, IEEE Trans. Information Technology in    Biomedicine, Vol. 4, 3,pp. 189-194, Sept. 2000.[2] Istepanian RSH, Modelling of GSM–based mobile telemedical system. Proc. 20th. IEEE Ann. Int. Conf.of the Engineering in Medicine and Biology Society, Hong Kong, pp. 926-930, 29 Oct-1 Nov,1998.[3] Leon-Garcia A & Widjaja I, Communication networks; Fundamental concepts and key Architectures.McGraw-Hill, Boston, N.Y., 2000[4] Istepanian RSH, Woodward B, Balos P, Chen S, and Luk B, The comparative performance of mobiletelemedical systems using the IS-54 and GSM cellular telephone standards. J. Telemedicine and Telecare,vol. 5, pp. 97-104,1999.Konstantinos Banitsas obtained his BSc and MSc degree from Portsmouth University, UK in 1994 and1996, respectively. He was extensively involved in the research areas of Digital Signal Processing androbotics. He was a lecturer at the Greek branch of the University of Portsmouth, teaching ElectronicEngineering and computers and currently pursuing his PhD research on the area of Telemedicine in BrunelUniversity, in collaboration with central Middlesex hospital.Dr. Robert H. Istepanian obtained his PhD degree from Loughborough University, UK in 1994. From 1984until 1988 he worked in different overseas industrial and academic positions. From 1996 to1999 he was aSenior Lecturer with the department of Electrical and Electronic Engineering, University of Portsmouth, UK.In 1999 he was visiting Associate Professor in the Department of Electrical and Computer Engineering,Ryerson Polytechnic University, Toronto. Presently he is a senior lecturer at Brunel University, WestLondon. He is recipient and investigator of research grants from the Royal Society – London. He hadpublished more than 90 refereed journal and conference papers and currently editing three books in the areasof wireless telemedicine, biomedical signal processing and control systems.Sapal Tachakra is the Director of A&E departments North West London NHS Hospital Trusts and aConsultant. He qualified as a medical practitioner in 1963 and as a surgeon in 1971. He was appointedconsultant in accident & emergency medicine in 1978. Published more than 100 scientific papers. Numerouspresentations at international conferences. Published 30+ papers on telemedicine. Largest follow up series onteleconsultation in the world.

[4] Istepanian

Istepanian obtained his PhD degree from Loughborough University, UK in 1994. From

of the Engineering in Medicine and Biology Society, Hong Kong,

The next generation of Wireless and Internetable Telemedicine Systems. Editorial Paper,

Applications of medical wireless LAN systems (MedLAN)

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