M2I Underground Wireless Sensor Networks · M2I Underground Wireless Sensor Networks: Physical...

M2I Underground Wireless Sensor Networks: Physical Layer Implementation

Dr. Zhi Sun Hongzhi Guo (PhD)

Darshit Makwana (MS)

Lynn SementilliJiaqi Xie

IntroductionObjective: ● To design and develop a physical layer test setup for the

metamaterial-enhanced magnetic induction (M2I) underground wireless sensor network (UWSN) communication system

● Verify accurate evaluation of the resulting bit error rates (BER) of various modulation types

Data Analysis• Model ideal BER for various input signal-to-noise

ratios using MATLAB • Determine the expected BER trend for the

modulation types• Use ideal BER calculation to verify that experimental

results will properly implement modulation types and BER calculations

Methods and EquipmentHardware• Ettus USRP N210 software defined radio• UBX-40 Daughterboard• PCB-designed MI loop antennas• PC with Ubuntu GNU Radio Companion installedAnalysis Methods• GNU Radio built-in modulation blocks in flowchart • Display BER and Tx/Rx signals in real-time GUI• Analyze saved binary files in Python and/or MATLAB

Results• GNU Radio Flow-chart produces the theoretical BER

trend for all types of tested modulation, thus verifying that the test setup should produce accurate measurements for modulations when using antennas in the underground environment

• Bare MI loop antennas achieve signal transmission but with limited range and accuracy, as expected

Conclusions• The developed GNU Radio test setup can be used

for conducting experiments in the underground environment with the M2I enclosed antennas

• Accurate readings of modulation BER can be read in real-time using the QT Time Sink as well as using the Python and/or MATLAB code to analyze saved binary files

References[1] Z. Sun; I. F. Akyildiz (2010, July). Magnetic Induction Communications for Wireless Underground Sensor Networks. IEEE Transactions on Antennas and Propagation. vol. 58, no. 7.[2] H. Guo; Z. Sun; J. Sun; N. M. Litchinitser (2015, Nov.) M2I: Channel Modeling for Metamaterial-Enhanced Magnetic Induction Communications. IEEE Transactions on Antennas and Propagation. vol. 63, no. 11[4] S. Haykin; M Moher, “Probability of Error Due to Noise,” in Communication Systems, 5th ed. Hoboken, NJ: John Wiley & Sons, Inc, 2009, ch. 8, sec. 3, pp. 285-290[5] S. Haykin; M Moher, “Digital Band-Pass Transmission Techniques,” in Communication Systems, 5th ed. Hoboken, NJ: John Wiley & Sons, Inc, 2009, ch.9, sec. 1-7, pp. 313-338[6] A. Goldsmith, “Performance of Digital Modulation over Wireless Channels,” in Wireless Communications, Stanford University, 2004, ch. 6, sec. 1, pp. 171-178

Future Research

Perform underground environment experimentation at fixed distances

Use the 3D-printed shell to enhance MI fields around currently tested coil antennas.

AcknowledgementsThis work was supported by the US National Science Foundation (NSF) under Grant No. 1547908

BackgroundApplications● Earthquake prediction, oil reservoirs, nuclear plants,

infrastructure monitoring, landscape management, homeland security, military uses

Magnetic Induction (MI) Antennas● Magnetic fields experience slight absorption and

multipath fadingMetamaterial-enhanced magnetic induction (M2I)● Used to enhance the magnetic field components and

increase the penetration strength of the fieldPhysical Layer in Electronics communications● Method of transferring data using bytesModulation ● Conversion of bits into a waveform: necessary to

transmit the information over the channel medium

Use tri-directional antenna for core of spherical device to produce omni-directional communication

● Develop Test Setup in GNU Radio Companion

● Conduct Ideal Modulation Simulations

● Perform initial Antenna and USRP tests using sinusoidal signal input

BPSK - Binary Phase Shift KeyingMSK - Minimum Shift KeyingQPSK - Quadrature Phase Shift KeyingBFSK - Binary Frequency Shift KeyingDPSK - Differential Phase Shift KeyingQAM - Quadrature Amplitude Modulation

Main Physical Layer Modulation Types

● Top - Amplitude Shift Keying (ASK)

● Middle - Frequency Shift Keying (FSK)

● Bottom - Phase Shift Keying

Figures 4&5: Transmitted and Received Relative Power from MI Loop Antenna Using Sinusoidal Signal Input

Figure 2: Bit Stream of Transmitted (Green) and Received (Red) Bits from Simulation - MATLAB Analysis

BPSK MATLAB Plot of Binary Data

Figure 9: GNU Radio Simulation of BPSK Transmission with AWGN

Figure 6: GNU Radio Test Setup for Modulation Simulation