1. doc: IEEE802.15-04/0360r0 Submission July 2004 K. Siwiak, TimeDerivative, Inc.Slide 1 Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs) Submission Title: [Near Filed Electromagnetic Ranging] Date Submitted: [13 July, 2004] Source: [Kazimierz Kai Siwiak] Company [TimeDerivative, Inc.] Address [10988 NW 14th Street, Coral Springs, FL, USA] Voice:[+1-954-937-3288], FAX: [--], E-Mail:[k.siwiak@ieee.org] Re: [ranging] Abstract:[Range determination does not require bandwidth, it can be done using near-field antenna techniques. Full 3-d location can be determined between one sensor and one target using distance and relative angle techniques.] Purpose:[Range determination can be accomplished using many techniques involving timing of signals. Accuracies of the timing methods are related to signal bandwidth. This material is intended to inform P802.15.4a about a distance determination technique involving predictable near-field antenna fields. When combined with phase-monopulse angle determination, full 3-d location is possible ] Notice:This document has been prepared to assist the IEEE P802.15. It is offered as a basis for discussion and is not binding on the contributing individual(s) or organization(s). The material in this document is subject to change in form and content after further study. The contributor(s) reserve(s) the right to add, amend or withdraw material contained herein. Release:The contributor acknowledges and accepts that this contribution becomes the property of IEEE and may be made publicly available by P802.15.

2. doc: IEEE802.15-04/0360r0 Submission July 2004 K. Siwiak, TimeDerivative, Inc.Slide 2 Location Using Near Field Techniques K. Siwiak, TimeDerivative, Inc.

3. doc: IEEE802.15-04/0360r0 Submission July 2004 K. Siwiak, TimeDerivative, Inc.Slide 3 Location Doesnt Need Bandwidth Distance measurements do not need large bandwidths Accuracies of centimeters are possible at Very Low Frequencies Time is not the only parameter to carry distance information Low frequency near-field techniques may be employed: Near Field EM Ranging

4. doc: IEEE802.15-04/0360r0 Submission July 2004 K. Siwiak, TimeDerivative, Inc.Slide 4 Small Loop E and H Fields Far field terms: 0 deg phase difference Near field terms: 90 deg phase difference

5. doc: IEEE802.15-04/0360r0 Submission July 2004 K. Siwiak, TimeDerivative, Inc.Slide 5 E and H Near Field Tracking Electric and Magnetic fields 90 deg out of phase in the near field; in-phase far away Phase difference varies predictably from 90 deg at antenna to 0 deg in far zone Good transition region between 0.05 and 0.4 wavelengths for accurate distance tracking

6. doc: IEEE802.15-04/0360r0 Submission July 2004 K. Siwiak, TimeDerivative, Inc.Slide 6 Basis of Near-Field Tracking 0 0.10.20.3 0.40.5 0.6 0 15 30 45 60 75 90 Phase difference E-field Phase H-field Phase distance, wavelengths phase, degrees Based on: Technical Introduction to Near Field Tracking, (Online): Q-Track Corp., 2003.

7. doc: IEEE802.15-04/0360r0 Submission July 2004 K. Siwiak, TimeDerivative, Inc.Slide 7 Phase Difference Yields Distance Locator 0.05 0.50 0.05 TX Beacon Locator Range( ) 0.50 TX Beacon Range( )

8. doc: IEEE802.15-04/0360r0 Submission July 2004 K. Siwiak, TimeDerivative, Inc.Slide 8 Near Field Tracking Accuracy Data Courtesy of: Q-Track Corporation

9. doc: IEEE802.15-04/0360r0 Submission July 2004 K. Siwiak, TimeDerivative, Inc.Slide 9 Can Be Used with Phase Monopulse Techniques for Location The relative angle to a signal can be found by signals a and b form two closely spaced antennas A and B Arithmetic network used to form a+b and a-b signals The ratio (a-b)/(a+b) is proportional to angle Technique is called phase monopulse and was associated with tracking systems over the past 40 years or so Four antennas (elevation and azimuth phase monopulse gives angle in two dimensions!

10. doc: IEEE802.15-04/0360r0 Submission July 2004 K. Siwiak, TimeDerivative, Inc.Slide 10 Azimuth Monopulse Tracking with Near Field Ranging a b found from E, H phase found from phase monopulse on E a, E b emitting target Can do similar phase monopulse in azimuth and elevation for full three dimensional LOCATION E-field: H-field:

11. doc: IEEE802.15-04/0360r0 Submission July 2004 K. Siwiak, TimeDerivative, Inc.Slide 11 Summary / Conclusions The phase difference between E and H fields directly relates to distance Phase difference in the range 0.05 to 0.4 wavelengths is suitable for accurate distance ( ) measurements Requires just a sinusoidal signal Can be used with angle determination (in one or two planes) to get location coordinates: ( )

12. doc: IEEE802.15-04/0360r0 Submission July 2004 K. Siwiak, TimeDerivative, Inc.Slide 12 Resources and Information Q-Track: http://www.q-track.com