OSA/OFC/NFOEC 2011
OTuF1.pdf OTuF1.pdf
Radio over Fiber Technology for Next-Generation E-Health in Converged Optical and Wireless Access Network Arshad Chowdhury, Hung-Chang Chien, Shu-Hao Fan, Jianjun Yu, Nikil Jayant and Gee-Kung Chang School of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA
[email protected]
(Invited) Abstract: Development of system technology for effective networking infrastructure for next generation e-health applications is addressed. An integrated optical wireless access architecture based on radio-over-fiber technology is proposed in order to provide super broadband, ultra lowlatency connectivity among various telemedicine modalities to facilitate real-time and near realtime communication for remote health care services. OCIS codes: (060.4510) Optical communications; (060.5625) Radio frequency photonics
1. Introduction Effective telecommunication and network infrastructure is an essential component of the next generation telehealth and telemedicine systems that requires exchanging electronic information of high resolution pathological and radiological images, real-time high-definition quality video for remote monitoring and diagnosis, telesurgery and other forms of medical services[1]-[4]. The telecommunication resources demanded by modern telehealth systems are dramatically increasing due to the rapidly changing nature of remote consultation services which are moving away from the past generation low bit-rate voice or text based phone consultation, to rich-media visual services [5]. Real-time delivery of multimedia content is necessary to increase patient reach by extending healthcare to the patients in the rural areas, to facilitate access to specialty care in large metropolitan areas with shortage of specialists, to request second opinion from remote medical experts, to support remote health monitoring and education etc. On the other hand, medical services such as teleradiology and telepathology require transmission of high resolution digital images with huge file sizes in the order of several hundred Gigabytes to Terabytes [6]. Transmission of such large images is a very challenging task because of the limited availability of, and the costs associated with high bandwidth telecommunication resources and particularly a major barrier for time-sensitive applications such as frozen section diagnosis, dynamic telepathology and real-time Teleradiology. Although, optical fiber based wired communication can satisfy the bandwidth requirements of next-generation telemedicine systems, however, wireless communication is still required to achieve mobility and greater flexibility in connecting the data acquisition sources of the complete telehealth system [7]-[9] Today, most of the hospital buildings support only closed wireless communication that limits the broadband adoption in the hospitals and healthcare facilities and acts as a chokepoint and obstacles to interconnectivity, upgradability and ultimately cost savings. Next-generation healthcare communication system has to be open access in nature by supporting protocol independent, multi-service, multi-carrier broadband services and applications. The frequency of the technology-neutral wireless communication services can range from few hundred MHz public safety and security systems (VHF, UHF etc.), 2G/3G mobile, 4G/Long Term Evolution (LTE), 2.4GHz WiFi up to 6GHz WiMAX services [7]-[14]. However, these lower frequency wireless services cannot provide adequate bandwidth and capacity required by next generation Telehealth systems to support transmission of high-resolution digital pathology and radiology images or HD quality video. Recently, wireless communication operating at 60-GHz millimeter-wave band has gained much attention for its huge unlicensed bandwidth of 7-GHz to achieve multigigabit data rate with efficient and low power consumption [10]. Nonetheless, penetration of wireless signal at various frequencies still poses a great challenge for indoor applications, especially in large hospital buildings and medical facilities. Thus converged optical and wireless system based on radio-over-fiber technology can solve the penetration problems of both the lower frequency legacy wireless services as well as future high frequency carriers at 60GHz for indoor facilities [11][12]. In this paper, we investigate an integrated converged network architecture and communication system for nextgeneration telemedicine using super broadband optical wireless radio-over-fiber technology. We envision that the proposed system can facilitate high quality, affordable healthcare in an accurate and secure way by providing protocol independent, multi-service, multi-carrier broadband connectivity between different modalities of a nextgeneration telemedicine system.
OSA/OFC/NFOEC 2011
OTuF1.pdf OTuF1.pdf
Clinics Pharmacies
Rural Area Service Providers
Hospitals
Backbone Network
FTTR
Wireless Access (3G, 4G/LTE, WiMAX, WiFi )
(Wireline,Wireless) Entreprise/ Private Network
(Fiber, 3G, 4G/LTE, WiMAX, WiFi, Public safety)
Wireless Access (3G, 4G/LTE, WiMAX, WiFi )
FTTH, FTTC (TDM/WDM PON)
RAU Optical Interface
RF Interface
LTE GSM, DCS, 3G UMTS WLAN (WiFi, WiMAX) Public Safety
Mobile care
Hospital Facility
TDM/WDM-PON Future services (60-GHz mm-wave)
IMGR
RF Interface
Health Plan Providers
Mobile nurse station (WiFi) Patient (LTE)
Optical Interface
Routing, Forwarding
IMGR
Optical Fiber
Portable X-ray
Signal Proces.
Resource Allocation
fMRI (fiber) Remote monitoring
Urban Area
(a)
IMGR: Intelligent Modality Gateway Router RAU: Remote Antenna Unit
(b)
Fig. 1. (a) Converged optical wireless network architecture of next-generation Telehealth communication systems. (b) Broadband optical wireless access for hospital facilities
2. Converged Optical Wireless System Architecture Fig. 1(a) shows the converged communication and network infrastructure that can provide transparent connectivity among various telehealth modalities located in many public and private healthcare entities. Entities like hospitals, medical schools, and diagnostic centers may be connected through dedicated private enterprise network as well as public service provider networks such as 2G, 3G, 4G/LTE mobile, WiMAX, or PON based broadband access as communication means. Fig. 1(b) shows the system architecture of the next-generation in-building radio-over-fiber networks that can seamlessly provide integrated multi-service broadband connectivity in large hospital buildings. The in-building fiber backbone is used to transmit both the wireless and wired signals among various fixed or mobile devices such as patient monitoring devices, radiology and pathology data acquisition devices and other text or multimedia enabled terminals used by the healthcare professionals, doctors, nurses, patients and hospital visitors. The unified architecture can provide high speed broadband connectivity directly through optical fiber for wired communication or through remote antenna unit (RAU) for mobile and portable devices using wireless radio-overfiber technology. The core of the architecture is the Intelligent Modality Gateway Router (IMGR). The IMGR provides signal processing for various protocol-independent wireless-band conversions (RF, Microwave, and millimeter wave), routing functionalities necessary media conversions, local buffering and storage, and authentication and security functions. Thus, IMGR plays the critical role of providing seamless connectivity among various in-hospital modalities and the external service provider’s wireless networks; thus, eliminate the in-building penetration limitations of the wireless signals. IMGR is also responsible for providing necessary light paths for various optical-wireless channels between different devices including automated protection and restoration mechanism for those channels. 3. Proof-of-concept Demonstration Fig. 2 shows a proof-of-concept experimental setup demonstrating integrated optical wireless network using 60GHz mm-wave radio-over- fiber technology to deliver protocol independent high resolution uncompressed pathological and radiological images from a medical data repository server to the remotely located interactive client terminals. We established a bi-directional real-time Gigabit wireless over fiber link between two telehealth modalities located in two research laboratories connected via Georgia Institute of Technology’s on-campus optical fiber networks. Both server and client terminals are equipped with PCI-Express Gigabit Ethernet Interface. The pathological image repository server contains multiple Z-stack slides of uncompressed high resolution digital pathology images of Glioblastoma WHO grade IV with each slide size of over 25GBytes. The downstream 1Gb/s output from the Server station located in Centergy Research Building is optically up-converted to 60-GHz mm-wave RF signal and transmitted over 2.5km optical fiber to the remote antenna unit (RAU) located in Technology Square Research Building (TSRB) at GT campus. At the RAU, the optical-wireless signal is received by a 60-GHz Photodiode (PD) and wirelessly broadcasted to the Client terminal through a pait of double-ridge guide rectangular o horn antennas with a gain of 15dBi, frequency range of 50 to 75 GHz and 22 E/H-plane 3-dB beam width. The optical input power to the PD is about 3 dBm and the PA electrical output power is about 5 dBm giving about 20 dBm equivalent isotropically radiated power (EIRP), which is well below the 40-dBm FCC power limit for in-
OSA/OFC/NFOEC 2011
OTuF1.pdf OTuF1.pdf
TSRB Building (Room 132) Centergy Building (Room 5188) RAU High Resolution Pathological Image Repository Server
SMF-28
Downstream Air Interface link
60G All-Optical Up-conversion GbE
PD
Tx
GT Fiber Backbone
60-GHz mmwave Radio over Fiber
Interactive Medical Image Evaluation
60-GHz Radio Receiver E/O
Rx Upstream link
SMF-28
Rx GbE
Tx
(a)
(b)
Fig. 2. Demonstration of converged optical wireless access for interactive high resolution pathological image transmission using gigabit wireless at 60-GHz mm-wave over fiber technology (a) proof-of-concept testbed setup (b) received high resolution pathological image at the client side.
building 60-GHz radio. At the client terminal, the broadcasted wireless signal is received and amplified before direct signal down-conversion using self mixing technique. A low pass filter (LPF) with 1.8 GHz bandwidth is used recover the 1 Gbps baseband data after the down-conversion. A 2.5Gbps optical transmitter is used to perform E/O conversion of the received 1Gbps baseband signal and fed into the receiver port of the Client terminal’s GbE interface. The upstream GbE link from the client to the Server is directly connected using optical fiber. Fig. 2(b) shows an instance of the received high resolution pathological image slides at the interactive client computer terminal. 4. Conclusions We proposed a broadband transport and access network architecture for next generation telemedicine and telehealth systems using integrated optical-wireless radio-over-fiber technology. It can conveniently provide protocolindependent connectivity among various telemedicine entities with existing or emerging wireless services such as public safety, 3G, 4G/LTE, WiFi and WiMAX together with future-proof 60-GHz mm-waveband wireless as well as PON based wired services for ultra low-latency real-time transmission of uncompressed super-high resolution images and video contents. A proof-of-concept experimental demonstration is carried out to established gigabit wireless over fiber link between the high resolution pathological image repository server and remotely located interactive client terminal. We believe that the proposed converged network system, when developed in close colaboration with the medical and health services communities, can facilitate new classes of next-generation telehealth and telemedicine services for timely high-quality, and affordable remote healthcare delivery. 4. References [1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14]
D.A. Perednia et a, “Telemedicine technology and clinical applications,” J. of American Medical Association, Vol. 273, pp. 483-488, 1995 O. Onguru et al, “Intra-hospital use of telepathology system,” Pathology oncology research , Vol. 6, No. 3, 2000 M.J. Su et al., “Application of tele-ultrasound in emergency medical services,” Telemedicine Journal and E-Health, Vol. 14, Oct. 2008 D.K. Kim et al, “A Mobile telemedicine system for remote consultation system in cases of acute stroke,” J. Telemedicine and Telecare, Vol. 15, pp. 102-107, 2009 I. Pratap et al, “Comparative technical evaluation of various communicationn media used for telemedical video-conference,” HealthCom 2008, July 2008, pp 1-2 DICOM Standard Committee, Working Groups 26, Pathology, “Digital Imaging and Communications in Medicine (DICOM) Supplement 145: Whole Slide Microscopic Image IOD and SOP Classes,” ftp://medical.nema.org/medical/dicom/supps/sup145_09.pdf Maria G. Martini, “Wireless Broadband Multimedia Health Services: Current Status and Emerging Concepts,” IEEE Personal Indoor and Mobile Radio Communications (PIMRC 2008), September, Cannes, France, (2008) A. Kailas et al, “Wireless communications technology in Telehealth systems,” Wireless VITAE 2009, pp 926-930 Tim Gee et al “An assessment of wireless medical telemetry system (WMTS), wireless medical devices,” Apr. 27 2008, http://medicalconnectivity.com/2008/04/27/an-assessment-of-wireless-medical-telemetry-system-wmts/ S. Pinel et al “A 90nm CMOS 60GHz Radio,” IEEE International Solid-State Circuits Conference, pp.130-131, Feb. 2008 G-K. Chang, Z. Jia, J. Yu, A. Chowdhury, “Super broadband optical wireless access technologies," OFC 2008, paper OThD A. Seeds, T. Ismail, “Broadband Access Using Wireless Over Multimode Fiber Systems,” JLT 28 (16), pp.2430-2435, August, 2010 A. Chowdhury, H-C Chien, Y-T Hsueh, G-K Chang, “Advanced System Technologies and Field Demonstration for In-Building OpticalWireless Network with Integrated Broadband Services,” J. of Lightwave technologies, vol. 27, no. 12, pp1920 – 1927, June 2009 Michael J. Crisp, Sheng Li, Adrian Wonfor, Richard V. Penty, and Ian H. White, “Demonstration of a Radio over Fibre Distributed Antenna Network for Combined In-building WLAN and 3G Coverage,” OFC 2007 paper JThA81
