Title:
分周回路及びそれを用いたマルチモード無線機
Document Type and Number:
Japanese Patent JP4246166
Kind Code:
B2
Abstract:
In a multimode radio, as many frequency dividers as the number of radio systems become necessary and the circuit scale of a frequency dividing section becomes large. A frequency dividing section 22 is made up of a frequency divider 19 for dividing output of a local oscillator, a frequency divider 20 for dividing output of an in-phase local oscillation signal of the frequency divider 19, and a dummy circuit 21 connected to the output terminal of a quadrature local oscillation signal of the frequency divider 19. At the first frequency band operation time, output of the frequency divider 19 is used for modulation and demodulation and at the second frequency band operation time, output of the frequency divider 20 is used for modulation and demodulation. Although the frequency divider 19 is shared between the first and second frequency bands, the dummy circuit is made the same circuit as an input amplifier of the frequency divider 20 at the first frequency band operation time, so that the phase difference between the in-phase local oscillation signal and the quadrature local oscillation signal output by the frequency divider 19 can be kept. Accordingly, the frequency dividers are shared and combined for lessening the circuit scale.
Inventors:
Hosokawa Yoshifumi
Noriaki Saito
Michiaki Matsuo
Katsuto Shimizu
Noriaki Saito
Michiaki Matsuo
Katsuto Shimizu
Application Number:
JP2005047649A
Publication Date:
April 02, 2009
Filing Date:
February 23, 2005
Export Citation:
Assignee:
Panasonic Corporation
International Classes:
H04B1/40; H03D7/00; H03D7/16; H03K21/00; H04B1/26
Domestic Patent References:
| JP2000124829A | ||||
| JP9261106A | ||||
| JP2002064397A | ||||
| JP2002280924A |
Attorney, Agent or Firm:
Shohei Oguri
Toshimitsu Ichikawa
Kimihide Hashimoto
Toshimitsu Ichikawa
Kimihide Hashimoto