ULF & VLF SDR Employing NBIR - Allerton 2019

Antenna

Performance

Gain:

Quality Factor & Inductance

Nagaoka

Formula

• Nagaoka Formula
• Wheeler Formula(s)
• Knight Formula

Schantz, Hans G., Alfred John Unden, M.A. Nikravan, and Do-Hoon Kwon, “Simple Formulas for Near-Field Transmission, Gain, and Fields,”

2013 Antenna Applications Symposium, Allerton Park,

Monticello, Illinois, September 17-19, 2013, pp. 360 – 384.

Inductance:

N: # of turns

K: shape factor

(elliptical integrals)

{

Nagaoka, H., “The Inductance Coefficients of Solenoids,” Journal of the College of Science, Imperial University, Tokyo, Japan, Vol. XXVII, Article 6, 1909.

Wheeler

Formula(s)

Knight

Formula

Wheeler, Harold A., “Simple Inductance Formulas for Radio Coils,” Proc. IRE, Vol. 16 No. 10, October 1928, pp. 1398-1400.

Wheeler, Harold A., “Inductance Formulas for Circular and Square Coils,” Proc. IEEE (Letters), Vol. 70, No. 12, Dec. 1982, p. 1449-1450.

Want to Learn More?

Hans G. Schantz, Principal Scientist

Geeks and Nerds Corporation

https://www.geeksandnerds.com

hans.schantz@geeksandnerds.com

Personal E-Mail: hans@hgschantz.com

Slides - check out: https://prezi.com/h4mzek7_xoah

https://gab.ai/aetherczar

https://twitter.com/aetherczar

Blog: http://www.aetherczar.com

Questions?

Introduction

Antenna Evaluation

Skin Depth

Wire Gauge & Resistance

ULF: 300 Hz - 3 kHz

VLF: 3 kHz - 30 kHz

Antenna Design

• Inductance
• Wire Gage & Resistance
• Transmit Antenna
• Receive Antenna

Transceiver Design

Link Behavior

Resistance

Wire Gauge

Summary

Gain vs Aspect Ratio

10xNBIR Performance:

~4m Antenna

~Few kW TX Power

~Few bit per minute

Global coverage!

Schantz, Hans G., Alfred John Unden, M.A. Nikravan, and Do-Hoon Kwon,

“Simple Formulas for Near-Field Transmission, Gain, and Fields,”

2013 Antenna Applications Symposium, Allerton Park, Monticello, Illinois, September 17-19, 2013, pp. 360 – 384.

Assuming 376 ohm?

United States Bureau of Standards, S.W. Stratton, Director,

“Circular of the Bureau of Standards No. 31 Copper Wire Tables,” 2nd ed., Washington: Government Printing Office, January 1, 1914, p. 15.

Explore:

• Multiple Resonance Antennas
• Higher order n

Next Steps:

• Demo &
• Characterize Two Antenna System
• Complete & Characterize 10xNBIR System

Example:

• n = 100; 100W EIRP; 10kW Average Power
• 100 MW Peak Power

Transmit

Antenna

Ultra-Low

Frequency (ULF) &

Very-Low Frequency (VLF) Software-Defined Radio (SDR)

Employing Narrow Band Impulse Radio (NBIR)

Hans G. Schantz, Principal Scientist

Geeks and Nerds Corporation

Huntsville, Alabama

hans.schantz@geeksandnerds.com

KC5VLD

Meeker, David C., Finite Element Method Magnetics, Version 4.2 (28Feb2018 Build),

http://www.femm.info.

Thursday, September 19, 2019

2019 Antenna Applications Symposium

Robert Allerton Park, Monticello, IL

10-Harmonic NBIR Design

Parsival's Dilemma:

Bandwidth Versus Duration

Traditional thinking:

Narrow Band or Short Time Duration. Pick One

Narrowband CW Versus UWB Impulse

NBIR TX PoC Design

SNR ~ "n"

NBIR

Best of Both

2

SNR ~n