发明名称 |
Direct-conversion receiver system and method, especially a GPS receiver system with high pass filtering |
摘要 |
<p>The invention relates to a direct conversion receiver and a method in a direct conversion receiver for processing received radio signals that are modulated and centered at a carrier frequency, the modulation extending a sideband above and below the carrier frequency. The method comprises the steps of mixing a local oscillator frequency signal with said received radio signals for generating baseband frequency signals; filtering out generated disturbing direct current (DC) components of said baseband signals centered at the zero frequency; setting said local oscillator frequency signal equal to or about the carrier frequency plus an offset frequency, said offset frequency being equal to the difference between the carrier frequency and a null frequency, said null frequency centered at a notch of said sideband; and centering said notch at the zero frequency of said baseband signals through mixing. The invention relates particularly to suppression of DC offsets generated in the receivers. <IMAGE></p> |
申请公布号 |
EP1220441(A2) |
申请公布日期 |
2002.07.03 |
申请号 |
EP20010660241 |
申请日期 |
2001.12.20 |
申请人 |
NOKIA CORPORATION |
发明人 |
ASIKAINEN, KALLE;TAKALO, TOMI-PEKKA |
分类号 |
H03D3/00;H04B;H04B1/26;H04B1/30;H04L27/22;(IPC1-7):H03D3/00 |
主分类号 |
H03D3/00 |
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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