Ultra Wideband Transceiver Design for Compact and Implantable

Abstract— Wireless health monitoring systems are becoming increasingly important with the development of new medical systems that require increased mobility and faster data rates. Ultra wideband (UWB) communication is becoming one of the most prevailing technologies that can accommodate some of the most critical requirements of a medical communication system. Since UWB has limited range capabilities due to the low signal power constrain by the spectral mask, performance could be impaired dramatically due to the interference that may exist in a medical environment such as an operating room. In this paper, we investigate a UWB communication system with simple Hadamard coding at the transmitter and energy detection at the receiver. The resulting system can be extremely compact and energy-efficient, making it suitable for implantable devices. We show simulation and analysis results with the proposed system in this paper.

Index Terms— Wireless health, Ultra wideband radio, Noncoherent detection and Hadamard coding.

I. INTRODUCTION here are several medical applications that can be implemented using the new wireless technologies.

Many medical conditions can benefit from the optimization of safe wireless communication systems. An example is monitoring the condition of a patient remotely, which may entail large amounts of data that may need to be transmitted in real time while maintaining information accuracy and precision. Other medical devices such as implantable devices and other applications such as chronic disease management, wellness and preventative medicine and telemedicine may benefit from the concepts presented in this paper.

Fig. 1, shows a relative comparison of several wireless

standards that may fit to be used for medical applications, the figure shows the data rate capability range of each standard versus the possible relative operation range. The operation range becomes an obstacle for medical device communication, since it can impair the mobility of the device and may result in a reduction in the possible data rate.

Authors are with the College of Engineering, San Diego State

University, San Diego, CA 92182, USA, Email: [email protected], {msarkar2, snagaraj, kmoon}@mail.sdsu.edu

This work has been funded by National Science Foundation – Engineering Research Center (NSF-ERC).

There are several wireless technologies currently being

used for wireless medical applications, those may include but not limited to, Bluetooth, Zigbee, and WiFi. Those technologies suffer from limited bandwidth, but can potentially provide various transmission ranges. UWB offers the luxury of high data rate transmission at the expense of a somewhat constrained range. A more detailed comparison between the various technologies can be found in [5]. Table I, shows a list of some common wireless technologies that can be used for wireless medical applications.

Table I: Potential Wireless Technologies for medical applications Wireless

Technology Frequency

Band Data Rate Transmitted

Power WLAN (802.11b/g)

2.4 GHz > 11 Mbps 250 mW

IEEE 802.15.1 (Bluetooth)

2.4 GHz 1 Mbps 20 dBm

IEEE 802.15.4 (Zigbee)

2.4 GHz 250 kbps 0 dBm

UWB 3.1 – 10.6 GHz

27.24 Mbps -41 dBm

Some of the medical applications that may benefit from

wireless radio technologies include: wireless ECG/EKG and respiratory information Systems, for patients with heart stroke risks; Accelerometer, Gyroscope and Electromyogram (EMG) sensor systems for monitoring patients with strokes; wearable BAN systems that collect vital sign and bio signals and transmission over a high speed phone link such as 4G LTE; wireless physiological sensors for implantable applications, for monitoring heart and prosthetic limb functions over a long period of time; some other applications may include monitoring blood pressure and weight, automatic emergency communications, and monitoring locations of equipment, doctors and patient via wireless links. UWB operates over a safe wireless band and it offers a number of major benefits that makes it most desirable over other technologies for the very low power consumption required for data transmission which helps in extending battery life of the transmitting device (wearable or implantable), also it has low interference effect on the other wireless systems in use in medical centers, and it offers high data rate to achieve the appropriate level of resolution required for physiological signals.

Ultra Wideband Transceiver Design for Compact and Implantable Medical Devices Faris Rassam, Mahasweta Sarkar, Santosh Nagaraj and Kee Moon

T

Proceedings of the World Congress on Engineering and Computer Science 2013 Vol II WCECS 2013, 23-25 October, 2013, San Francisco, USA

ISBN: 978-988-19253-1-2 ISSN: 2078-0958 (Print); ISSN: 2078-0966 (Online)

WCECS 2013

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WCECS 2013

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REFERE

“Digital Comnd ed., Prentice HPerformance of Hnd, James Freeberi, A non-cohDigital Implemen) Gao, Multi-Bao,ZhenmingFen

y image (with co

CLUSIONS a novel UWB or medical apsimple and pohe receiver is

The system and reliabilitiend power-effi

hat require smsimulation r

ONS AND FUTU

ns that can mn enhance UWer data rate cthis type of cored a big dea

mitting deviceorder imperiaper, and for o for UWB tems can be us

ment that can he system runain threshold

nt one to yield

EDGMENT ted by the Nensorimotor S

ENCES mmunications, F

Hall P T R, 2008, cHard Decision Deersyser,1999. herent Ultra-Wintation, MIT, 200and UWB systemng,2003.

ding)

communicatipplications. Tower efficient made simple can easily

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URE WORK make use of thWB usage in tcapabilities woding is easy al of processie. ally validate t

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[5] Jin-Shyan Lee, A comparative Study of Wireless Protocols:Bluetooth,UWB,ZigBee,andWi-Fi,Yu-WeiSu,Chung-ChouShen,2007. [6] Jee-HeyLee,ImprovedPerformanceofSoftDecisionDecodingforDCM in MB-OFDM system, Myung-Sun Baek, Hyoung-Kyu Song,2008. [7] Asawari Chinchanikar, Overview:MB-OFDM UWB System, RSKawitkar, VSRD International Journal of Electrical, Electronicsand Communication Engineering, VSRD-IJEECE, vol.2 (6), 2012,314-321. [8] Julien Ryckaert1, Ultra-WideBand Transmitter for Wireless Body

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[9] Nazlı Guney, Capacity and Mutual Information of Soft and Hard Decision Output M-ary PPM over UWB Channels, Hakan Delic, Fatih Alagoz, Bogazici University.

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[11] Jae Ho Hwang, The Spectrum Sensing Algorithm Using the Soft Decision Algorithm in Cognitive UWB System, Jong Seok Park, Jae Moung Kim.

[12] Benoıt Miscopein, Multipath Decision Fusion for Low Complexity UWB-IR Non-Coherent Receivers, Jean Schwoerer, Orange LABS, Jean-Marie Gorce, University of Lyon.

[13] Tianqi Wang , Link Energy Minimization in IR-UWB Based Wireless Network, Wendi Heinzelman, Alireza Seyedi.



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Ultra Wideband Transceiver Design for Compact and Implantable

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