Title:
INTERFERENCE WAVE CANCELLING DEVICE
Document Type and Number:
Japanese Patent JP3301735
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To sufficiently cancel even an interference wave spread over a frequency band with a significant width by filtering a signal branched from a main line signal with a prescribed narrow band BPF and generating a cancellation signal so that a relation of nearly the same level and the opposite phase is established between the main line signal and the cancellation signal over the entire prescribed frequency band.
SOLUTION: This interference wave cancelling device is provided with a cancellation circuit 10B with a flat phase IF narrow band BPF 20B. The BPF 20B is configured to have two signal paths, a main signal path and a delay path. The main signal path has a broad band BPF whose pass band center frequency is (f0) and whose delay time is (τt), and the delay path has a narrow band BPF whose pass band center frequency is (f0) and whose delay time is (τd), an attenuator whose signal attenuation rate is a fixed value (K) and a phase shifter whose phase shift amount is set to obtain a signal with an inverted phase with respect to the signal via the main signal path from the delay path.
Inventors:
Kazuo Yamashita
Hironori Sakamoto
Tomohiro Sanbe
Tamaki Honda
Hiroshi Morita
Hironori Sakamoto
Tomohiro Sanbe
Tamaki Honda
Hiroshi Morita
Application Number:
JP34846298A
Publication Date:
July 15, 2002
Filing Date:
December 08, 1998
Export Citation:
Assignee:
Japan Radio Co., Ltd.
International Classes:
H03H11/00; H04B1/10; H04L1/00; H04B1/12; H04B15/00; (IPC1-7): H04B1/10; H04L1/00
Domestic Patent References:
| JP1177610U | ||||
| JP374873B2 |
Attorney, Agent or Firm:
Kenji Yoshida (2 outside)
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