| 摘要 |
PROBLEM TO BE SOLVED: To provide a terrestrial digital multimedia broadcasting (DMB) tuner of a low intermediate frequency (IF) structure which is applied to a mobile communication terminal, such as a mobile phone, and an image rejection mixer applied thereto. SOLUTION: In order to improve inter-channel attenuation characteristics, the image rejection mixer locates an oscillation frequency above or beneath the frequency of a target signal to include an image signal of the target signal in a terrestrial DMB band, mixes a radio frequency (RF) signal with the oscillation frequency, and outputs the resulting IF signals to a polyphase filter in a selected arrangement. Because the image signal of the target signal is included in the terrestrial DMB band, the image rejection mixer can satisfy the inter-channel attenuation characteristics without a troublesome or complex design and even if the oscillation frequency is located above or beneath the frequency of the target signal, an image component included in the IF signal can be removed. Furthermore, a terrestrial DMB tuner of a low IF structure including such an image rejection mixer is included. COPYRIGHT: (C)2006,JPO&NCIPI
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