| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a high frequency module which can be made small and attain a high function and prevents a low frequency side attenuation characteristic of a SAW (surface acoustic waveguide) filter from deteriorating by reducing parasitic impedance in the SAW filter. <P>SOLUTION: The high frequency module comprises a power amplifier composed of a semiconductor element for power amplification and a matching circuit constituting at least a high frequency part, a filter for eliminating noise of a signal to be inputted to the power amplifier, a directional coupler and a detection circuit for detecting an output of the power amplifier and a duplexer for dividing transmission and reception signals on the surface of or inside a dielectric board obtained by laminating dielectric layers, and a terminal for external connection on the bottom of the dielectric board, wherein a semiconductor element for power amplification of the power amplifier and a filter for transmission of the duplexer are mounted on the surface side of a module board, a cavity is provided on the bottom side of the module board, and the filter for transmission of the duplexer is housed and mounted in the cavity. <P>COPYRIGHT: (C)2006,JPO&NCIPI</p> |
