Invention Grant
US06940840B2 Apparatus for adaptive reverse power control for spread-spectrum communications
失效
用于扩频通信的自适应反向功率控制的装置
- Patent Title: Apparatus for adaptive reverse power control for spread-spectrum communications
- Patent Title (中): 用于扩频通信的自适应反向功率控制的装置
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Application No.: US09791026Application Date: 2001-02-21
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Publication No.: US06940840B2Publication Date: 2005-09-06
- Inventor: Faith M. Ozluturk , Gary R. Lomp , John Kowalski
- Applicant: Faith M. Ozluturk , Gary R. Lomp , John Kowalski
- Applicant Address: US DE Wilmington
- Assignee: InterDigital Technology Corporation
- Current Assignee: InterDigital Technology Corporation
- Current Assignee Address: US DE Wilmington
- Agency: Volpe and Koenig, P.C.
- Main IPC: G06F13/374
- IPC: 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 ; H04B7/216

Abstract:
A code-division-multiple-access (CDMA) system employing spread-spectrum modulation. The CDMA system has a base station (BS), and a plurality of subscriber units. The signals transmitted between the base station and subscriber unit use spread-spectrum modulation. The improvement method for adaptive reverse power control (APC) from a subscriber unit (SU) to a base station (BS), comprises the steps of sending from the subscriber unit, using spread-spectrum modulation, a SU-spreading code on a reverse channel. The base station despreads the SU-spreading code on the reverse channel as a despread signal, determines a first power level Pd which includes power of the despread signal plus noise and a second power level PN, which includes despread-noise power. The base station determines a first error signal e1, from the first power level Pd, the second power level PN, and a required signal-to-noise ratio SNRREQ for service type, and a second error signal e2, from a measure of total received power Prt at the base station, and an automatic gain control (AGC) set point Po. The base station forms a combined error signal from the first error signal e1, the second error signal e2, a first weight a1, and a second weight a2, and hard limits the combined error signal to form a single APC bit. The APC bit is transmitted to the subscriber unit. In response to the APC bit, the subscriber adjusts transmitter power to the base station.
Public/Granted literature
- US20020034169A1 Apparatus for adaptive reverse power control for spread-spectrum communications Public/Granted day:2002-03-21
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