ULTRA WIDE BAND BODY AREA NETWORK

1. ULTRA WIDE BAND
WIRELESS BODY AREA
NETWORKS
Guide: Dr.Lillykutty Jacob Presented By:
Aravind M.T
M.Tech II Sem
Dept.of ECE
NITC

2. CONTENTS OF THE PRESENTATION
 Objective /Goals
 Introduction
 Why BAN?
 Why UWB?
 Basic Requirements
 Topology
 Existing System
 Proposed System
 Propagation Channel Model
 MAC Algorithm
 Conclusion
 References
9 February 2017 2Dept. of ECE , NITC

3. GOALS
 Understanding UWB-BANs.
 Appreciating their ‘potency’.
 Being aware of their current applications .
 Understanding the challenges on the horizon.
 Understanding proposed models.
 Understanding various topologies.
9 February 2017 3Dept. of ECE , NITC

4. INTRODUCTION
 Increasing population and the rising costs of health care have triggered the introduction of novel
technology-driven enhancements to current health care practices.
 Recent advances in electronics have enabled the development of small and intelligent (bio-)
medical sensors which can be worn on or implanted in the human body.
 Thus introduced Wireless Body Area Network (WBAN).
 Wireless body area network (WBAN) is a collection of wireless sensors placed around or in a
human body that are used to collect important information wirelessly.
 Recently, ultra-wideband (UWB) wireless technology is used for wireless body area network
(WBAN) applications.
Benefits : low-power transmitter, low radio frequency (RF) and electromagnetic
interference effects in medical environment, small size antenna and high data rate.
9 February 2017 4Dept. of ECE , NITC

5. What is BAN…???
Definition by IEEE 802.15.6:
“A communication standard optimized for low power devices for
their operation on, in or around the human body (but not limited to
humans) to serve a variety of applications including medical,
consumer electronics or personal entertainment and other.”
9 February 2017 5Dept. of ECE , NITC

6. What is UWB…???
Ultra wideband (also known as UWB or as digital pulse wireless) is
a wireless technology for transmitting large amounts of digital data
over a wide spectrum of frequency bands with very low power for a
short distance.
9 February 2017 6Dept. of ECE , NITC

7. Basic requirements of a WBAN
 Limited transmission range .
 Extremely low power consumption in sleep mode.
 Support of scalable data rate ranging from 1kbps to several Mbps.
 QoS support for critical physiological data.
 Low latency over a multi-hop network.
 Small form factor and light weight devices.
9 February 2017 7Dept. of ECE , NITC

8. ADVANTAGES & DRAWBACKS - UWB
Advantages:
Usage of IR-UWB
 Pulse Based Nature-Simpler Modulation Scheme
 Power Saving
 Less hardware Complexity
 High data rate
Drawbacks:
Receiver Complexity
9 February 2017 8Dept. of ECE , NITC

9. EXISTING SYSTEM-RESEARCH CHALLENGES
1.Frequency Band Selection:
1. Most BAN devices need global operability.
2. Facility for low-power usage (less crowded).
3. Less stringent rules for flexible usage and adaptability.
4. Solutions proposed: Use UWB standard ,an operational bandwidth from
wide spectrum ranges from 3.1-10 GHz.
` 9Dept. of ECE , NITC

10. 2. PHY Protocol Design:
1)Minimize power consumption.
Solution: Quick turn-around from transmit to receive and fast wake-up from sleep
mode.
3. Energy-Efficient Hardware:
1. Today’s wireless technologies draw relatively high peak current.
2. Also rely on duty cycling between sleep and active.
Solution: Operation on low peak pulse-discharge current from thin-film (paper)
batteries, idle listening.
EXISTING SYSTEM-RESEARCH CHALLENGES CONTD…
9 February 2017 10Dept. of ECE , NITC

11. 4. Technical Requirements:
1. Wide variation in data rate, BER, delay tolerance, duty cycle and lifetime.
2. Diverse application environments.
5. Security
1. More resource-efficient and light weight security protocols.
EXISTING SYSTEM-RESEARCH CHALLENGES CONTD…
9 February 2017 11Dept. of ECE , NITC

12. Focuses upon:
1. Rate adaptable MAC protocol for UWB .
2. A preamble sampling multiple access protocol for UWB network.
3. A transmit-only MAC protocol.
PROPOSED SYSTEM
9 February 2017 12Dept. of ECE , NITC

13. Topology of WBAN for a multi-human monitoring environment
9 February 2017 13Dept. of ECE , NITC

14. A DUAL BAND (UWB-TRANSMIT AND NARROWBAND-RECEIVE)
APPROACH FOR WBAN
Communication protocols for WBAN (a) transmitter and receiver both use UWB (b) UWB transmit-only (c) mixed band
9 February 2017 14Dept. of ECE , NITC

15. UWB AND NARROW BAND PHYSICAL LAYER
IR-UWB pulse generation
9 February 2017 15Dept. of ECE , NITC

16. UWB NARROW BAND PHYSICAL LAYER
Propagation channels involved
9 February 2017 16Dept. of ECE , NITC

17. Path loss at a distance ‘d’ can be calculated as;
P dB(d)=P0,dB+a(d/d0)n + N(µ(d), σ2(d))
 d  depth from skin in millimeters
 d0  reference distance
 P0, dB  Path loss at reference distance
 a  Fitting Constant
 n  Path Loss Exponent
PROPAGATION CHANNEL MODEL
9 February 2017 17Dept. of ECE , NITC

18. Average path loss(L) of IR-UWB signals at a distance of ‘d’ is given by,
 fc  (fmin*fmax )1/2
 fmin & fmax  -10dB edges of the waveform Spectrum.
 c  Velocity of Light
d  Distance relative to 1m reference point
PROPAGATION CHANNEL MODEL CONTD…
L1 = 20 log (4 π fc/c) , L2=20 log (d) and L=L1+L2
9 February 2017 18Dept. of ECE , NITC

19. UWB –PULSE MODULATION SCHEME
 BPPM (Binary Pulse Position Modulation)
 Two mechanisms to ensure transmit power effectively
1. Use Gated Pulse Transmission Scheme.
2. Dynamically Varying Pulse per Bit Scheme.
9 February 2017 19Dept. of ECE , NITC

20. UWB –PULSE MODULATION SCHEME Contd…
(a) two PPB and (b) three PPB in BPPM.
9 February 2017 20Dept. of ECE , NITC

21. POWER LIMITATIONS OF THE GATED UWB PULSE
TRANSMISSION
 Full bandwidth (FBW) peak power of UWB signal is 1mW for low PRF systems.
 Assumed resolution BW ,1 MHz
 PRF for proposed UWB based WBAN sensor node is 100MHz, which is high.
 Hence considered High Pulse Repetition Frequency System.
Ppeak <= 7.5x10-8 (Bp/R)2 x 1/𝛿 W
Ppeak <= 0.001(BR/50 x 106)2 x (Bp/R)2 W
 Bp = 1/ T , T is Pulse Width
 BR = Resolution Bandwidth
 R = Pulse Repetition Frequency
 𝛿 = Duty Cycle
9 February 2017 21Dept. of ECE , NITC

22. Variation of full bandwidth peak power with duty cycle
9 February 2017 22Dept. of ECE , NITC

23. BER Analysis of Multiple PPB Scheme
IR-UWB receiver model
n(t) if there is no pulse present in a time time slot
r(t) = s(t)+n(t) if there is a pulse present in a time slot
n
B
(t) if there is no pulse present in a time time slot
r’(t) = sB(t)+n
B
(t) if there is a pulse present in a time slot
9 February 2017 23Dept. of ECE , NITC

24. BER ANALYSIS OF MULTIPLE PPB SCHEME
9 February 2017 24Dept. of ECE , NITC

25. BER ANALYSIS OF MULTIPLE PPB SCHEME
Considering MAI and MPI ,modified form of Probability of Error for Single Pulse
Detection of the Receiver with BPPM Modulation Scheme
Pe=Q √(Ep/N0)2/2 (Ep/N0+TsB+M)
N(0,M) --------- Interference Distribution
9 February 2017 25Dept. of ECE , NITC

26. Bit error rate (BER) Vs. pulse Ep/No (dB) curves for different
number of PPB
9 February 2017 26Dept. of ECE , NITC

27. Super Frame Structure and Timing
9 February 2017 27Dept. of ECE , NITC

28. MAC ALGORITHM
9 February 2017 Dept. of ECE , NITC 28
Turn on
Waits and receive beacon on the
NB channel and synchronizes
super frame structure
Sends RTS(Preamble Sequence + sensor ID) in one
of the first two time slots of the CAP
Listens to the CTS on NB Channel
CTS
Received?
End of Initialization
Waits Random Back off time
No
Parent Node sends CTS Message
Yes

29. MAC ALGORITHM Contd…
9 February 2017 Dept. of ECE , NITC 29
Data to send
Waits and receive beacon on the
NB channel and synchronizes
super frame structure
Sends data in a previously
assigned GTS using assigned
PPB
Parent Node determines the Bit
Error Rate and whether a PPB
change is required
PPB
changed ?
Go to Low Power Mode
Data to send=Previous Data
Yes

30. MAC ALGORITHM Contd…
9 February 2017 Dept. of ECE , NITC 30
Data to send
Sensor Initialization (starts from
position in a)
Waits and receive beacon on the NB channel and
synchronizes super frame structure
Sends data in a previously assigned PDS using assigned
PPB
PPB
changed?
Parent node sends ACK
Data to send=Previous Data
Parent Node determines the Bit Error Rate and whether
a PPB change is required
Ack rcvd?
Discards Packet from memory , stores the last assigned
PPB and go to Low power mode.
Waits Random Back off time.
N
Y

31. Network Topologies used in Simulations
9 February 2017 31Dept. of ECE , NITC

32. PERMORMANCE PARAMETERS…
PER PULSE TRANSMIT POWER ALLOCATION (PPTP)
CRUCIAL FACTOR IN DETERMINING THE PULSE SIGNAL TO NOISE RATIO
PPTP= FBW TRANSMIT POWER / DUTY CYCLE * PRF
9 February 2017 32Dept. of ECE , NITC

33. PERMORMANCE PARAMETERS CONTD…
 NORMALIZED THROUGHPUT(%)
R(bps)/C(bps)x100%
R  Total Data Bit Rate
C  Total Network Capacity
 PACKET LOSS RATIO
PL=L/S
PL  Packet Loss
L  Total No: of Lost Packets
S  Total No: of Send Packets
9 February 2017 33Dept. of ECE , NITC

34. 9 February 2017 Dept. of ECE , NITC 34
PERMORMANCE PARAMETERS CONTD…
E(J/bit)=(( 𝑖=0
𝐾
(𝐼 𝐴 ∗ 𝑉 𝑉 ∗ 𝑇𝑡𝑥 − 𝑟𝑥 𝑠𝑒𝑐 )/ 𝑖=0
𝐾
B)
D=T1-T2
E(J/bit)  Consumed Energy at a Sensor Node per useful data bit.
I(A)  Consumed current of Sensor Node.
V(V)  Battery Voltage.
Ttx-rx (sec) sum of Transmission time per data packet and reception time for ack’s.
B  Total no: of useful bit.
K  Total no: of packet sent.
D  Packet Acknowledgement Delay for Periodic Traffic.
T1  Actual Time at which packet is acknowledged.
T2  Time at which packet enters the Transmission Queue.

35. VARIATION OF AVERAGE PACKET LOSS RATIO WITH THE
INCREASE OF NUMBER OF SENSORS
9 February 2017 35Dept. of ECE , NITC

36. Average Packet Acknowledgement Delay
Variation of the average packet acknowledgement delay (seconds)
for periodic traffic with increasing number of sensor nodes for two
topologies with and without narrow band feed back
9 February 2017 36Dept. of ECE , NITC

37. PERCENTAGE THROUGHPUT
Variation of the percentage throughput for each sensor
type in the two simulated topologies
9 February 2017 37Dept. of ECE , NITC

38. ENERGY CONSUMPTION
Variation of consumed energy by a sensor node per useful data
bit (in nJ) with increasing number of sensor nodes for two
topologies and for sensor nodes with narrowband receivers and
sensor nodes with UWB receivers.
9 February 2017 38Dept. of ECE , NITC

39. Comparison with Existing MAC Protocols…TABLE 5
9 February 2017 39Dept. of ECE , NITC

40. CONCLUSION
 Ultra-wide band wireless technology does not present an EMI risk to other narrow band
systems since its transmitter power is quite low and the frequencies used are at very high
frequencies.
 Dual band is proposed for WBAN sensor nodes to achieve a power consumption while
maintaining a good QOS.
 Using a router as an intermediate node improves the data transmission within a WBAN.
 Minimizes the power consumption and packet delays for a UWB-based WBAN sensor node
using a narrow band receiver.
 Lower transmission power will increase the battery lifespan of the WBAN sensor nodes.
9 February 2017 40Dept. of ECE , NITC

41. REFERENCES
1) Kasun M. S. Thotahewa, Jamil Y. Khan, Mehmet R. Yuce, “Power Efficient Ultra Wide Band Based Wireless
Body Area Networks with Narrowband Feedback Path”, IEEE TRANSACTIONS ON MOBILE COMPUTING,
VOL. 13, NO. 8, AUGUST 2014.
2) K.M.S. Thotahewa, J.-M. Redoute, M.R. Yuce, “Medium access control (MAC) protocols for ultra-wideband
(UWB) based wireless body area networks (WBAN), ultra-wideband and 60 GHz communications for biomedical
applications”, ISBN: 978-1-4614 8895-8, Springer, 2013.
3) Chee Keong Hoa, Terence S.P. Seeb, Mehmet R. Yucec, “An ultra-wideband wireless body area network:
Evaluation in static and dynamic channel conditions” Sensors and Actuators A 180 , 137– 147,ELSEVIER 2012.
4) Hiroki Katsuta 1, Yuichiro Takei 1, Kenichi Takizawa2, Tetsushi Ikegami , “Experiments of Ultra Wideband-
based Wireless Body Area Networks with Multi-Nodes Attached to Body”, IEEE 2014.
9 February 2017 Dept. of ECE , NITC 41

42. REFERENCES
5. L. Huan-Bang and R. Kohno, “Introduction of SG-BAN in IEEE 802.15 with related discussion,” in Proc.
IEEE ICUWB, pp. 134–139, Sep. 2007.
6. Yuichiro TAKEI, Hiroki KATSUTA, Kenichi TAKIZAWA, Tetsushi IKEGAMI, Kiyoshi HAMAGUCHI,
“Prototype Ultra Wideband-based Wireless Body Area Network -Consideration of CAP and CFP slot
allocation during human walking motion” 34th Annual International Conference of the IEEE EMBS San
Diego, California USA, 28 August - 1 September, 2012.
7. Part 15.4: Wireless Medium Access Control (MAC) and Physical Layer (PHY) Specifications for Low-Rate
Wireless Personal Area Networks (LR-WPANs), IEEE Standard 802.15.4-2006, 2007.
8. www.zigbee.org.
9 February 2017 Dept. of ECE , NITC 42

43. 9 February 2017 43Dept. of ECE , NITC