发明名称 |
Code division multiple access mobile communication system |
摘要 |
<p>A code division multiple access (CDMA) mobile communication system with improvements to permit stable reception with a minimum of bit error. The system comprises a voltage-controlled oscillator (63) for supplying a carrier to a radio frequency quadrature demodulator (57), and a frequency controller (70) for detecting a frequency error from a phase correction signal of the first step to generate a control signal that controls the oscillator (63). The frequency controller (70) includes an extracting circuit and an integrating circuit. The extracting circuit extracts a phase change based on the frequency error derived from the phase correction signal of the first step and from a signal preceding that signal by a predetermined delay time. The integrating circuit integrates the phase change and outputs the integrated result as the control signal. The predetermined delay time is preferably set within a range not exceeding the delay time needed for averaging by an averaging circuit that receives the phase correction signal of the first step and outputs a phase correction signal. The carrier to a radio frequency quadrature modulator (66) is preferably supplied from the voltage-controlled oscillator (63).</p> |
申请公布号 |
EP0762666(A3) |
申请公布日期 |
2003.08.06 |
申请号 |
EP19960114399 |
申请日期 |
1996.09.09 |
申请人 |
HITACHI, LTD. |
发明人 |
OHGOSHI, YASUO;YANO, TAKASHI;DOI, NOBUKAZU |
分类号 |
H04J13/00;H04B1/707;H04B1/7087;H04B7/26;H04B14/06;H04W88/00;(IPC1-7):H04B1/707;H04L27/00 |
主分类号 |
H04J13/00 |
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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