| US 7,613,434 B2 | ||
| Multiplexer and wireless receiver | ||
| Fumihiko Aiga, Yokohama (Japan); Hiroyuki Kayano, Fujisawa (Japan); Tatsunori Hashimoto, Yokohama (Japan); and Noritsugu Shiokawa, Yokohama (Japan) | ||
| Assigned to Kabushiki Kaisha Toshiba, Tokyo (Japan) | ||
| Filed on Mar. 14, 2007, as Appl. No. 11/686,048. | ||
| Claims priority of application No. 2006-215446 (JP), filed on Aug. 08, 2006. | ||
| Prior Publication US 2008/0037590 A1, Feb. 14, 2008 | ||
| Int. Cl. G06F 3/033 (2006.01); H04B 1/26 (2006.01) | ||
| U.S. Cl. 455—130 [455/323; 455/327] | 12 Claims |
| 1. A multiplexer comprising:
a first band-pass filter for a first channel, which is formed in a microstrip line on a dielectric substrate and has a first
branching characteristic having a center frequency of f1 and an attenuation pole at a frequency of fa1; and
a second band-pass filter for a second channel, which is formed in a microstrip line on a dielectric substrate and has a second
branching characteristic having a center frequency of f2 and an attenuation pole at a frequency of fa2,
wherein the following relationships (1) to (5) are satisfied:
f1<f2 (1);
f1<fa1 (2);
fa2<f2 (3);
f2−fa1<(f2−f1)/2 (4); and
fa2−f1<(f2−f1)/2 (5), and
wherein the second branching characteristic exhibits −20 dB or less at the frequency of fa1 and the first branching characteristic exhibits −20 dB or less at the frequency of fa2.
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