Power control device and method for controlling a reverse link common channel in a CDMA communication system

Abstract

A common power control channel transmission device for a base station in a CDMA communication system is provided having a selector for receiving power control commands to be transmitted to multiple subscribers and multiplexing the received power control commands; and a spreading modulator for spreading an output of the selector by multiplying the output of the selector by a spreading sequence. The common power control channel transmission device can be used to control power of a reverse link common channel. For the power control of the reverse link common channel, the base station receives a signal from a mobile station via the reverse link common channel, and transmits to the mobile station a power control command for controlling a transmission power of the reverse link common channel according to a measured strength of the received signal.

What is claimed is:  
     
         1 . A method for controlling a reverse link common channel in a base station of code division multiple access (CDMA) communication system, comprising the steps of: 
 receiving a signal transmitted from a mobile station via the reverse link common channel;    generating a power control command depending upon the strength of the received signal of reverse link common channel, for controlling a transmission power of the reverse link common channel;    pseudo-randomly selecting the position that the power control command is inserted in a forward link common power control channel;    inserting power control command in the selected position of the forward link common power control channel; and    transmitting to the mobile station the power control command via the common power control channel.    
     
     
         2 . The method as claimed in  claim 1 , wherein said reverse link common channel is a reverse link common channel.  
     
     
         3 . The method as claimed in  claim 1 , wherein said reverse link common channel is an enhanced access channel.  
     
     
         4 . The method as claimed in  claim 1 , wherein the signal of the reverse link common channel is a preamble signal and/or a message signal.  
     
     
         5 . The method as claimed in  claim 1 , wherein said base station transmits a power-up command to the mobile station until said signal is acquired.  
     
     
         6 . A device for controlling a reverse link common channel in a base station of code division multiple access (CDMA) communication system, comprising: 
 a common power control command generator for generating power control command of reverse link common channel; and    a common power control channel transmitter for pseudo-randomly selecting the position that the power control command is inserted in a forward link common power control channel and transmitting to the mobile station power control command via the common power control channel.    
     
     
         7 . The method as claimed in  claim 6 , wherein said reverse link common channel is a reverse link common channel.  
     
     
         8 . The method as claimed in  claim 6 , wherein said reverse link common channel is an enhanced access channel.  
     
     
         9 . A common power control channel transmission device for a base station in a code division multiple access (CDMA) communication system, comprising: 
 slot controller for pseudo-randomly selecting a position in order to insert a power control command transmitted via a common power control channel;    a selector for inserting the power control command in the selected position of the common power control channel;    an orthogonal modulator for orthogonally modulating an output of the selector with an orthogonal code for the common power control channel; and    a spreading modulator for a spreading the output signal of orthogonal modulator with a PN spreading sequence and transmitting the spreading signal.    
     
     
         10 . The base station device as claimed in  claim 9 , further comprising a scrambler for scrambling the received power control command of multiple subscribers with user's pseudo random sequence respectively and transmitting the selector.  
     
     
         11 . The base station device as claimed in  claim 9 , wherein the common power control channel is used by multiple subscribers on a time-division basis.  
     
     
         12 . The base station device as claimed in  claim 11 , wherein the common power control channel transmitter uses a signal orthogonal code.