发明名称 |
Mobile communication apparatus |
摘要 |
A transceiver suitable for larger scale of integration employs direct conversion reception for reducing the number of filters. Also, the number of VCOs is reduced by utilizing dividers to supply a receiver and a transmitter with locally oscillated signals at an RF band. Dividers each having a fixed division ratio are used for generating locally oscillated signals for the receiver, while a divider having a switchable division ratio are used for generating the locally oscillated signal for the transmitter. In addition, a variable gain amplifier for baseband signal is provided with a DC offset voltage detector and a DC offset canceling circuit for supporting high speed data communications to accomplish fast cancellation of a DC offset by eliminating intervention of a filter within a feedback loop for offset cancellation.
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申请公布号 |
US7366489(B2) |
申请公布日期 |
2008.04.29 |
申请号 |
US20030742813 |
申请日期 |
2003.12.23 |
申请人 |
TTPCOM LIMITED;RENESAS TECHNOLOGY CORP. |
发明人 |
TANAKA SATOSHI;WATANABE KAZUO;HOTTA MASAO;HONGO TOYOHIKO;YAMAWAKI TAIZO;KASAHARA MASUMI;TAKIKAWA KUMIKO |
分类号 |
H04B1/06;H04B1/40;H04B1/10;H04B1/30;H04B1/38;H04B7/00;H04M;H04M1/00;H04Q7/32 |
主分类号 |
H04B1/06 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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