发明名称 |
Centroid tracking for spread-spectrum communications |
摘要 |
A multiple access, spread-spectrum communication system processes a plurality of information signals received by a radio carrier station over telecommunication lines for simultaneous transmission over a radio frequency channel as a code-division-multiplexed signal to a group of subscriber units. The radio carrier station receives a call request signal that corresponds to a telecommunication line information signal, and a user identification signal that identifies a user to receive the call. The radio carrier station includes a plurality of CDMA modems, one of which provides a global pilot code signal. The modems provide message code signals synchronized to the global pilot signal. Each modem combines an information signal with a message code signal to provide a code division multiplexed signal. The RCS includes a system channel controller is coupled to receive a remote call. A radio frequency transmitter is connected to all of the modems to combine the code division multiplexed processed signals with the global pilot code signal to generate a code division multiplexed signal. The transmitter also modulates a carrier signal with the code division multiplexed signal and transmits the modulated carrier signal through a radio frequency communication channel to the subscriber units. Each subscriber unit includes a CDMA modem which is also synchronized to the global pilot signal. The CDMA modem despreads the code division multiplexed signal and provides a despread information signal to the user. The system includes a closed loop power control system for maintaining a minimum system transmit power level for the radio carrier station and the subscriber units, and system capacity management for maintaining a maximum number of active subscriber units for improved system performance.
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申请公布号 |
US2002044539(A1) |
申请公布日期 |
2002.04.18 |
申请号 |
US20010765016 |
申请日期 |
2001.01.18 |
申请人 |
OZLUTURK FATIH M.;LOMP GARY R. |
发明人 |
OZLUTURK FATIH M.;LOMP GARY R. |
分类号 |
G06F13/374;H03H17/02;H03H17/06;H04B1/707;H04B7/005;H04B7/26;H04J13/00;H04J13/04;H04L1/00;H04L5/14;H04L25/02;H04L27/00;H04L27/20;H04L27/233;H04N1/333;(IPC1-7):H04B7/216 |
主分类号 |
G06F13/374 |
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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