Galvanically isolated, directional coupler

Patent metadata

Field	Value
Publication number	US-9413053-B2
Application number	US-201214236645-A
Country	US
Kind code	B2
Filing date	Jul 16, 2012
Priority date	Aug 4, 2011
Publication date	Aug 9, 2016
Grant date	Aug 9, 2016

Abstract

A galvanically isolated, directional coupler, especially for in- and out-coupling of high-frequency measurement signals of a radar fill-level measuring device, wherein two mutually engaging, oppositely bent, conductive traces are provided, wherein the two oppositely bent, conductive traces are so arranged that that they couple with one another over a region of a quarter wavelength (λ/4) of the wavelength associated with the center frequency of the measuring signals and form two groups of laterally coupled, conductive traces, and wherein curved conductive trace portions adjoin each of the two groups of laterally coupled, conductive traces, in each case, over a region, which is less than an eighth wavelength (λ/8) of the wavelength associated with the center frequency.

First claim

The invention claimed is:

1. A galvanically isolated, directional coupler for in- and out-coupling of high-frequency measurement signals of a radar fill-level measuring device, comprising:
two mutually engaging, oppositely bent, conductive traces, wherein the two oppositely bent, conductive traces are so arranged that conductive trace portions couple with one another over a region of a quarter wavelength (λ/4) of the wavelength associated with the center frequency of the measuring signals and form two groups of laterally coupled, conductive trace portions, wherein:
curved conductive trace portions adjoin each of said two groups of laterally coupled, conductive trace portions, in each case, over a region, which is less than an eighth of a wavelength (λ/8) of the wavelength associated with the center frequency, in a way such that said two groups of laterally coupled, conductive trace portions and curved conductive trace portions are configured in a way so that the coupler has a rounded shape, and
wherein said directional coupler is constructed of at least one SMD component.

2. The galvanically isolated directional coupler as claimed in claim 1 , wherein:
said SMD component is a capacitor.

3. The galvanically isolated directional coupler as claimed in claim 1 , wherein:
said at least one SMD component comprises two equally constructed resistors.

4. The galvanically isolated directional coupler as claimed in claim 1 , wherein:
the at least one component is arranged in a horizontal plane of a circuit board or wherein the at least one component is arranged in at least two parallel planes of a circuit board.

5. A galvanically isolated, directional coupler for in- and out-coupling of high-frequency measurement signals of a radar fill-level measuring device, comprising:
two mutually engaging, oppositely bent, conductive traces, wherein the two oppositely bent, conductive traces are so arranged that conductive trace portions couple with one another over a region of a quarter wavelength (λ/4) of the wavelength associated with the center frequency of the measuring signals and form two groups of laterally coupled, conductive trace portions, wherein:
curved conductive trace portions adjoin each of said two groups of laterally coupled, conductive trace portions, in each case, over a region, which is less than an eighth of a wavelength (λ/8) of the wavelength associated with the center frequency, in a way such that said two groups of laterally coupled, conductive trace portions and curved conductive trace portions are configured in a way so that the coupler has a rounded shape, and
wherein:
two transitions between the bent, laterally coupled, conductive traces and the bent conductive traces are so embodied that the high-frequency measuring signals are transmitted with an as great as possible bandwidth.

6. A galvanically isolated, directional coupler for in- and out-coupling of high-frequency measurement signals of a radar fill-level measuring device, comprising:
two mutually engaging, oppositely bent, conductive traces, wherein the two oppositely bent, conductive traces are so arranged that conductive trace portions couple with one another over a region of a quarter wavelength (λ/4) of the wavelength associated with the center frequency of the measuring signals and form two groups of laterally coupled, conductive trace portions, wherein:
curved conductive trace portions adjoin each of said two groups of laterally coupled, conductive trace portions, in each case, over a region, which is less than an eighth of a wavelength (λ/8) of the wavelength associated with the center frequency, in a way such that said two groups of laterally coupled, conductive trace portions and curved conductive trace portions are configured in a way so that the coupler has a rounded shape, and, wherein:
said conductive traces have a toothed structure.

7. A galvanically isolated, directional coupler for in- and out-coupling of high-frequency measurement signals of a radar fill-level measuring device, comprising:
two mutually engaging, oppositely bent, conductive traces, wherein the two oppositely bent, conductive traces are so arranged that conductive trace portions couple with one another over a region of a quarter wavelength (λ/4) of the wavelength associated with the center frequency of the measuring signals and form two groups of laterally coupled, conductive trace portions, wherein:
curved conductive trace portions adjoin each of said two groups of laterally coupled, conductive trace portions, in each case, over a region, which is less than an eighth of a wavelength (λ/8) of the wavelength associated with the center frequency, in a way such that said two groups of laterally coupled, conductive trace portions and curved conductive trace portions are configured in a way so that the coupler has a rounded shape, and

wherein:
said directional coupler is so dimensioned that it acts as a 3 dB coupler.

8. A transmitting/receiving separator for a radar fill-level measuring device, comprising:
a directional coupler as claimed in claim 1 ; and
a terminating element, respectively a high frequency sink, which is provided at one of at least four ports of said directional coupler.

9. The transmitting/receiving separator as claimed in claim 8 , wherein:
said terminating element, respectively the high frequency sink, comprises a resistor, which has double the resistance of the line wave resistance respectively impedance, and a match structure.

10. A transmitting/receiving separator for a radar fill-level measuring device, comprising:
a galvanically isolated, directional coupler comprising two mutually engaging, oppositely bent, conductive traces,
wherein the two oppositely bent, conductive traces are so arranged that the conductive trace portions couple with one another over a region of a quarter wavelength (λ/4) of the wavelength associated with the center frequency of the measuring signals and form two groups of laterally coupled, conductive traces, wherein curved conductive trace portions adjoin each of said two groups of laterally coupled, conductive traces, in each case, over a region, which is less than an eighth of a wavelength (λ/8) of the wavelength associated with the center frequency; and
a terminating element, respectively a high frequency sink, which is provided at one of at least four ports of said directional coupler,
wherein said terminating element, respectively the high frequency sink, comprises a resistor, which has double the resistance of the line wave resistance respectively impedance, and a match structure, and
wherein said match structure comprises three mutually connected, conductive trace portions of defined length and width and two vias to the reference potential ply of a circuit card.

11. The transmitting-receiving separator as claimed in claim 8 , wherein:
the three remaining ports of said directional coupler are connected to an antenna, a transmitting unit and a receiving unit of the radar fill level measurement device.

Assignees

• Blodt Thomas
• Endress Hauser Gmbh Co Kg

Inventors

• Blodt Thomas

Classifications

• H01P5/185 Primary

  Edge coupled lines · CPC title

• H01P5/186

  Lange couplers · CPC title

• H01P5/184 Primary

  the guides being strip lines or microstrips · CPC title