APPARATUS FOR MEASUREMENT DE-EMBEDDING AND METHODS FOR USE THEREWITH

• US 20180159592A1
• Filed: 12/06/2016
• Published: 06/07/2018
• Est. Priority Date: 12/06/2016
• Status: Active Grant

• Current Assignee: AT&T Intellectual Property I LP (AT&T, Inc.)
• Original Assignee: AT&T Intellectual Property I LP (AT&T, Inc.)
• Inventors: RAPPAPORT, Harold, BARZEGAR, Farhad, GERSZBERG, Irwin, HENRY, Paul Shala
• Granted Patent: US 10,326,494 B2
• Time in Patent Office: Days
• CPC Class Codes: H04B 3/46 Monitoring; Testing
• CPC Class Codes: H04B 3/52 Systems for transmission between fixed stations via waveguides

Abstract

Aspects of the subject disclosure may include, a transmission medium having a first end configured to be coupled to a first port of the launching device, wherein electromagnetic waves are induced by the launching device on a surface of the transmission medium, wherein the electromagnetic waves are bound to the surface of the transmission medium, and wherein the electromagnetic waves propagate without requiring an electrical return path to a second end of the transmission medium. A short circuit, coupled to the second end of the transmission medium, reflects the electromagnetic waves back to the first end of the transmission medium for reception by the launching device as reflected electromagnetic waves at the first port to facilitate a de-embedding of the launching device. Other embodiments are disclosed.

Claims

1. An apparatus for use with a launching device, the apparatus comprising:

a transmission medium having a first end configured to be coupled to a first port of the launching device, wherein electromagnetic waves are induced by the launching device on a surface of the transmission medium, wherein the electromagnetic waves are bound to the surface of the transmission medium, and wherein the electromagnetic waves propagate without requiring an electrical return path to a second end of the transmission medium; and

a short circuit, coupled to the second end of the transmission medium, that reflects the electromagnetic waves back to the first end of the transmission medium for reception by the launching device as reflected electromagnetic waves at the first port to facilitate a de-embedding of the launching device in a measurement of a device under test.

2. The apparatus of claim 1, wherein a network analyzer generates a first microwave signal on a second port of the launching device that causes the launching device to induce the electromagnetic waves on the surface of the transmission medium, wherein the network analyzer receives a second microwave signal from the launching device caused by the reflected electromagnetic waves and the first microwave signal.

3. The apparatus of claim 2, wherein two-port s-parameters of the launching device are generated based on an analysis of the second microwave signal.

4. The apparatus of claim 3, wherein the analysis of the second microwave signal includes performing an inverse Fourier transform on the second microwave signal to generate a transformed second microwave signal and interpreting terms portions of the transformed second microwave signal corresponding the reflected electromagnetic waves as terms in a power series expansion.

5. The apparatus of claim 3, wherein the analysis of the second microwave signal includes performing an inverse Fourier transform on the second microwave signal, finding a first term from a power series and determining a difference between the second microwave signal and the first term.

6. The apparatus of claim 1, wherein the transmission medium is one of:

a bare wire, an insulated wire or a conductorless dielectric fiber and wherein the electromagnetic waves have a fundamental frequency within a microwave frequency band.

7. The apparatus of claim 1, wherein the short circuit comprises a reflection plate.

8. The apparatus of claim 7, wherein the reflection plate is oriented perpendicular to a longitudinal axis of the transmission medium.

9. The apparatus of claim 7, wherein the reflection plate has a metallic surface that reflects the electromagnetic waves.

10. The apparatus of claim 7, wherein the reflection plate is adhered to the transmission medium via an epoxy.

11. A method for use with a launching device, the method comprising:

coupling a calibration apparatus to the launching device, the calibration apparatus including a transmission medium having a first end configured to be coupled to a first port of the launching device, and the calibration apparatus further including a short circuit, coupled to a second end of the transmission medium;

generating a first microwave signal on a second port of the launching device that causes the launching device to induce electromagnetic waves on a surface of the transmission medium, wherein the electromagnetic waves are bound to the surface of the transmission medium, wherein the electromagnetic waves propagate without requiring an electrical return path to a second end of the transmission medium and wherein the electromagnetic waves are reflected by the short circuit back to the first end of the transmission medium for reception by the launching device as reflected electromagnetic waves at the first port;

receiving a second microwave signal from the launching device caused by the reflected electromagnetic waves and the first microwave signal; and

analyzing the second microwave signal to de-embed the launching device from a microwave system that comprises the launching device and a device under test.

12. The method of claim 11, wherein the analyzing the second microwave signal includes determining parameters of the launching device.

13. The method of claim 12, wherein the analyzing the second microwave signal includes performing an inverse Fourier transform on the second microwave signal to generate a transformed second microwave signal and interpreting terms portions of the transformed second microwave signal corresponding to the reflected electromagnetic waves as terms in a power series expansion.

14. An apparatus for measuring a launching device, the apparatus comprising:

transmission means for propagating electromagnetic waves without requiring an electrical return path from a first end of the transmission means coupled to a first port of the launching device to a second end of the transmission means, wherein electromagnetic waves are induced by the launching device on a surface of the transmission means, and wherein the electromagnetic waves are bound to the surface of the transmission means; and

reflection means for reflecting the electromagnetic waves back to the first end of the transmission means for reception by the launching device as reflected electromagnetic waves at the first port.

15. The apparatus of claim 14, wherein the transmission means is a bare or insulated wire.

16. The apparatus of claim 14, wherein the transmission means is a conductorless dielectric fiber and wherein the electromagnetic waves have a fundamental frequency within a microwave frequency band.

17. The apparatus of claim 14, wherein the reflection means comprises a reflection plate.

18. The apparatus of claim 17, wherein the reflection plate is oriented perpendicular to a longitudinal axis of the transmission means.

19. The apparatus of claim 17, wherein the reflection plate has a metallic surface that reflects the electromagnetic waves.

20. The apparatus of claim 17, wherein the reflection plate is adhered to the transmission means via an epoxy.

21. The apparatus of claim 14, wherein the transmission means includes a wire having an insulating jacket, wherein the launching device includes a dielectric stub coupler with a tapered end that induces the electromagnetic waves on a surface of the insulating jacket, wherein the electromagnetic waves propagate via a non-fundamental mode, and wherein a field strength of a first portion of the electromagnetic waves outside of the insulating jacket is greater than a field strength of a second portion of the electromagnetic waves inside of the insulating jacket.