Directional coupler

• US 20040005814A1
• Filed: 06/06/2003
• Published: 01/08/2004
• Est. Priority Date: 06/27/2002
• Status: Active Grant

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Kathrein-Werke KG. (Kathrein SE)
• Inventors: Krause, Rainer, Kummer, Bernhard
• Granted Patent: US 6,882,243 B2
• Time in Patent Office: Days
• US Class Current: 439/578
• CPC Class Codes: H01P 5/183 at least one of the guides being a coaxial line

Abstract

An improved directional coupler is distinguished by the following features:

an attenuation circuit (27) is adjacent and is connected to each of the two coupling line ends (25) on the coupler substrate (19′), or an attenuation circuit (27) is connected to one coupling line end (25) with a terminating resistor (49) being connected to the other coupling line end (25) on the coupler substrate (19′),

electrical level evaluation (33) is provided on the coupler substrate (19′), and

an interface device (35) for connection of possibly unshielded cables (41) is provided on the coupler substrate (19′), or possibly unshielded cables (41) are connected to the level evaluation circuit device or are connected downstream from this on the coupler substrate (19′), via which the RF signals which are obtained via the coupling line piece (23) can be passed on in the form of analog signals.

Claims

1. Directional coupler having at least one coupling line piece (23) which is coupled to a coaxial inner conductor (5) of coaxial line pieces (1) and, for this purpose, the coupling line piece (23) is provided on or adjacent to a coupler substrate (19′

) which is arranged on a resting or mounting section (11) of the outer conductor (3) of the coaxial line piece (1) in the region of a cutout (15) in the outer conductor (3), and the coupling line piece (23) is in this way held in the space between the inner conductor (5) and the outer conductor (3), characterized by the following further features;

an attenuation circuit (27) is adjacent and is connected to each of the two coupling line ends (25) on the coupler substrate (19′

), or an attenuation circuit (27) is connected to one coupling line end (25) with a terminating resistor (49) being connected to the other coupling line end (25) on the coupler substrate (19′

),

electrical level evaluation (33) is provided on the coupler substrate (19′

), and

an interface device (35) for connection of possibly unshielded cables (41) is provided on the coupler substrate (19′

), or possibly unshielded cables (41) are connected to the level evaluation circuit device or are connected downstream from this on the coupler substrate (19′

), via which the RF signals which are obtained via the coupling line piece (23) can be passed on in the form of analog AF signals.

2. Directional coupler according to claim 1, characterized in that the attenuation circuit (27) is in the form of a Π

circuit (R1, R2, R3).

3. Directional coupler according to claim 1, characterized in that the attenuation circuit (27) is in the form of a T circuit (R4, R5, R6).

4. Directional coupler according to one of claims 1 to 3, characterized in that a level detector (33) is provided on the coupler substrate (19′

), preferably adjacent to or downstream from each of the two coupling line ends (25).

5. Directional coupler according to one of claims 1 to 4, characterized in that a memory module (37) which is preferably in the form of an EEPROM memory module (37) is also provided on the coupler substrate (19′

) and is used to store the transfer function of at least one and preferably both coupling arms, and of electronic evaluation.

6. Directional coupler according to one of claims 1 to 5, characterized in that the coupler substrate (19′

) has a multilayer structure.

7. Directional coupler according to one of claims 1 to 6, characterized in that the coupler substrate (19′

) has a central section (19a) in the region of the exposed cutout (15) in the outer conductor (3) in the coaxial line piece (1), and in that an additional extension section (19b) is provided at least in a lateral direction from this central section (19a), for holding further electrical or electronic components.

8. Directional coupler according to one of claims 1 to 7, characterized in that the coupling line piece (23) is in the form of a stripline, a wire clip or a wired component, preferably in the form of a resistor.

9. Directional coupler according to one of claims 1 to 8, characterized in that the electronic components are fitted or provided on the upper face of the coupler substrate (19′

) and/or on the lower face of the coupler substrate (19′

).

10. Directional coupler according to one of claims 1 to 9, characterized in that elements for temperature compensation are furthermore also provided on the coupler substrate (19′

).

11. Directional coupler according to one of claims 1 to 10, characterized in that, in addition to assemblies for detecting absolute level information, the directional coupler also has assemblies for detecting difference values between the level and phase between the two coupling arms (A, B).

12. Directional coupler according to one of claims 1 to 11, characterized in that components which determine a frequency, in particular bandpass filters (31) or bandstop filters, are provided in at least one coupling arm (A, B), preferably in both coupling arms (A, B), in particular for suppressing interference frequencies.

13. Directional coupler according to one of claims 1 to 12, characterized in that the directional coupler preferably also has a microprocessor (43) on the coupler substrate (19′

).