CDMA communication system and its transmission power control method

Abstract

An uplink channel transmission power control method is provided for a CDMA mobile communication system performing one way communication. A base station measures the received level of data transmitted from each mobile terminal at each channel, and generates a transmission power control signal of each uplink traffic channel. The generated transmission power control signals are multiplexed, and the multiplexed common transmission power control signal is transmitted to all mobile terminals by using the common channel shared by the mobile terminals. Each mobile terminal derives the transmission power control signal of the uplink traffic channel used by the terminal, from the received common transmission power control signal, and controls the transmission power of a data packet.

1 - 26 . (canceled)  
     
     
         27 . A base station for communicating with a plurality of mobile terminals in a wireless communication system having a plurality of channels to be used for each of said mobile terminals and a common channel to be shared by said plurality of mobile terminals, comprising: 
 a generator for generating a transmission power control signal for a mobile terminal;    a transmission radio module for modulating said transmission power control signal; and    an antenna for transmitting said modulated transmission power control signal to said mobile terminal via said common channel.    
     
     
         28 . A base station according to  claim 27 , further comprising a reception circuit for receiving a packet from one of the plurality of mobile terminals, wherein said generator generates a transmission power control signal for a mobile terminal which transmitted the received packet in response to the reception of said packet.  
     
     
         29 . A base station according to  claim 28 , further comprising a unit for measuring a received level of said received packet, wherein said generator generates the transmission power control signal for said mobile terminal based on said measured received level.  
     
     
         30 . A base station according to  claim 27 , wherein said transmission power control signal is transmitted to said mobile terminal together with an ID information for said mobile terminal.  
     
     
         31 . A base station according to  claim 27 , wherein said transmission power control is for controlling a transmission power of an uplink channel for said mobile terminal, and said transmission power control signal is transmitted according to said uplink channel for said mobile terminal.  
     
     
         32 . A transmission power control method for a spectrum wireless communication system having a base station and a plurality of mobile terminals which communicate using a plurality of channels to be used for each of said mobile terminal and a common channel to be shared by said plurality of mobile terminals, wherein; 
 said base station generates a transmission power control signal for a mobile terminal, modulates said transmission power control signal, and transmits said modulated transmission power control signal to said mobile terminal via said common channel.    
     
     
         33 . A transmission power control method according to  claim 32 , wherein said base station transmits said modulated transmission power control signal to said mobile terminal via said common channel when there is not provided a downlink traffic channel for said mobile terminal.  
     
     
         34 . A transmission power control method according to  claim 32 , wherein said base station receives a packet transmitted from a mobile terminal and generates a transmission power control signal for said mobile terminal in response to reception of said packet.  
     
     
         35 . A transmission power control method according to  claim 34 , wherein said base station measures the received level of the packet received from said mobile terminal and generates said transmission power control signal according to said measured received level.  
     
     
         36 . A transmission power control method according to  claim 32 , wherein said mobile terminal receives said transmission power control signal transmitted from said base station, demodulates said received transmission power control signal, and controls a transmission power of a packet to be transmitted to said base station according to said demodulated transmission power control signal.  
     
     
         37 . A transmission power control method according to  claim 32 , wherein said modulated transmission power control signal is transmitted to said mobile terminal together with an ID information for said mobile terminal.  
     
     
         38 . A transmission power control method according to  claim 32 , wherein said transmission power control is for controlling a transmission power of an uplink channel for said mobile terminal, and said modulated transmission power control signal is transmitted according to said uplink channel.  
     
     
         39 . A transmission power control method for a base station in a wireless communication system having a base station and a plurality of mobile terminals which communicate using a plurality of channels to be used for each of said mobile terminals and a common channel to be shared by said plurality of mobile terminals, having the steps of: 
 generating a transmission power control signal for a mobile terminal;    modulating said transmission power control signal in a transmission radio module; and    transmitting, from an antenna, said modulated transmission power control signal to said mobile terminal via said common channel.    
     
     
         40 . A transmission power control method according to  claim 39 , wherein said modulated transmission power control signal is transmitted when a downlink traffic channel for said mobile terminal is not provided.  
     
     
         41 . A transmission power control method according to  claim 39 , further having the step of receiving a packet from said mobile terminal prior to generating said transmission power control signal, wherein the base station generates said transmission power control signal in response to the reception of said packet.  
     
     
         42 . A transmission power control method according to  claim 41 , further having the step of measuring a received level of said received packet, wherein said transmission power control signal is generated according to said measured received level.  
     
     
         43 . A transmission power control method according to  claim 39 , wherein said transmission power control signal is transmitted to said mobile terminal together with an ID information for said mobile terminal.  
     
     
         44 . A transmission power control method according to  claim 39 , wherein said transmission power is for controlling a transmission power of an uplink channel for said mobile terminal, and said transmission power control signal is transmitted according to said uplink channel for said mobile terminal.  
     
     
         45 . A mobile terminal for communicating with a base station in a wireless communication system having a plurality of channels to be used for each mobile terminal and a common channel to be shared by a plurality of mobile terminals, comprising: 
 a reception circuit for receiving a transmission power control signal transmitted from said base station via a common channel shared by a plurality of mobile terminals;    a demodulator for demodulating said transmission power control signal; and    a controller for controlling transmission power for transmitting signals to said base station.    
     
     
         46 . A mobile terminal according to  claim 45 , wherein said reception circuit receives said transmission power control signal transmitted together with an ID information for said mobile terminal.  
     
     
         47 . A mobile terminal according to  claim 45 , wherein said transmission circuit transmitting said data packet via an uplink channel for said mobile terminal which is not paired with a downlink channel for said mobile terminal.  
     
     
         48 . A mobile terminal according to  claim 38 , wherein said transmission power control signal is received according to said uplink channel for said mobile terminal.