发明名称 |
Code division multiple access mobile communication system |
摘要 |
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 for supplying a carrier to a radio frequency quadrature demodulator, and a frequency controller for detecting a frequency error from a phase correction signal of the first step to generate a control signal that controls the oscillator. The frequency controller 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 is preferably supplied from the voltage-controlled oscillator.
|
申请公布号 |
US2002196768(A1) |
申请公布日期 |
2002.12.26 |
申请号 |
US20020217404 |
申请日期 |
2002.08.14 |
申请人 |
OHGOSHI YASUO;YANO TAKASHI;DOI NOBUKAZU |
发明人 |
OHGOSHI YASUO;YANO TAKASHI;DOI NOBUKAZU |
分类号 |
H04J13/00;H04B1/707;H04B7/26;H04B14/06;(IPC1-7):H04B7/216 |
主分类号 |
H04J13/00 |
代理机构 |
|
代理人 |
|
主权项 |
|
地址 |
|