Title:
DIRECTIONAL COUPLER
Document Type and Number:
WIPO Patent Application WO/2011/102187
Kind Code:
A1
Abstract:
Disclosed is a directional coupler which has excellent characteristics even when parasitic inductance is present in the coupling line. A directional coupler (11R) is constructed by providing a resistor (Rx) between a signal input port (23) and a CPL (coupling) port (25) and also between a signal output port (24) and an ISO (isolation) port (26). By providing the resistors (Rx) in this way, a real-number-component cancelling signal can be input to the coupling line (22) through the resistors (Rx), and the output of the ISO port (26) can therefore be reduced and directionality can be improved. That is, by adjusting the resistors (Rx) to have a resistance value which cancels the real number component of parasitic inductance (Lp) present in the coupling line (22), the output (isolation) of the ISO port (26) becomes substantially zero, thereby making it possible to improve directionality. It is therefore possible to realise a directional coupler which has excellent characteristics.
Inventors:
MUKAIYAMA KAZUTAKA (JP)
Application Number:
PCT/JP2011/051276
Publication Date:
August 25, 2011
Filing Date:
January 25, 2011
Export Citation:
Assignee:
MURATA MANUFACTURING CO (JP)
MUKAIYAMA KAZUTAKA (JP)
MUKAIYAMA KAZUTAKA (JP)
International Classes:
H01P5/18
Foreign References:
| JP2009044303A | 2009-02-26 | |||
| JPS5350645A | 1978-05-09 | |||
| JPS60120601A | 1985-06-28 | |||
| JP2009260288A | 2009-11-05 |
Attorney, Agent or Firm:
Kaede Patent Attorneys' Office (JP)
Patent business corporation Kaede Patent Attorneys' Office (JP)
Patent business corporation Kaede Patent Attorneys' Office (JP)
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