Monitoring of CDMA load and frequency reuse based on reverse link signal-to-noise ratio

Abstract

A system and method for monitoring the load on a CDMA communication system having a base station and a plurality of users. A measure of voice activity in the communication system is determined, and a current value of frequency reuse efficiency equal to an initial value of frequency reuse efficiency is provided. A power determination is made according to the measured voice activity and the current value of frequency reuse efficiency. The current value of frequency reuse efficiency is updated using the power determination to provide a new current value of frequency reuse efficiency. The power determination and the update of the frequency reuse efficiency are iteratively repeated until convergence to provide a converged value of frequency reuse efficiency. The load on the communication system is then determined according to the converged frequency reuse efficiency value.

What is claimed is:  
     
         1 . A digital signal processing apparatus to estimate loading in a spread spectrum wireless communication system, comprising the steps of: 
 receive circuitry; and    processor communicatively coupled to the receive circuitry, the processor capable of executing commands and data to estimate loading of the system by: 
 determining frequency reuse of the system; and  
 determining loading of the system as a function of the frequency reuse.  
   
     
     
         2 . The apparatus of  claim 1 , wherein determining the frequency reuse of the system, comprises determining a power associated with voice activity to determine the frequency reuse.  
     
     
         3 . The method of  claim 2 , wherein determining the frequency reuse of the system is an iterative process.  
     
     
         4 . The method of  claim 3 , wherein the frequency reuse F k (n+1) is calculated as:  
       
         
           
             
               
                 
                   F 
                   k 
                 
                  
                 
                   ( 
                   
                     n 
                     + 
                     1 
                   
                   ) 
                 
               
               = 
               
                 
                   P 
                    
                   
                     ( 
                     n 
                     ) 
                   
                 
                 
                   
                     P 
                     t 
                   
                   - 
                   
                     
                       N 
                       o 
                     
                      
                     W 
                   
                 
               
             
           
           
           
               
           
         
         wherein Pt is total power received at receive circuitry, P is the power of spread spectrum frames, and N o W represents background noise received at the base station.  
       
     
     
         5 . The apparatus of  claim 4 , wherein the loading is determined in accordance with the following equation:  
       
         
           
             
               L 
               = 
               
                 
                   1 
                   
                     F 
                     k 
                   
                 
                  
                 
                   
                     ∑ 
                     
                       i 
                       = 
                       1 
                     
                     N 
                   
                    
                   
                     
                       
                         v 
                         i 
                       
                        
                       
                         x 
                         i 
                       
                     
                     
                       
                         W 
                         / 
                         
                           R 
                           i 
                         
                       
                       + 
                       
                         
                           1 
                           F 
                         
                          
                         
                           v 
                           i 
                         
                          
                         
                           x 
                           i 
                         
                       
                     
                   
                 
               
             
           
           
           
               
           
         
         where F k  is the converged frequency reuse efficiency value, v i  corresponds to a voice activity factor, R i  is the data rate of a user of the communication system, and x i  is the energy per bit to noise power spectral density of a reverse traffic channel in the communication system.  
       
     
     
         6 . The apparatus of  claim 5 , wherein the voice activity factor is equal to one indicating a data communication.  
     
     
         7 . A digital signal processing apparatus to process communications in a spread spectrum wireless communication system, comprising the steps of: 
 receive circuitry; and    processor communicatively coupled to the receive circuitry, the processor capable of executing commands and data to estimate loading of the system by: 
 determining frequency reuse of the system;  
 determining loading of the system as a function of the frequency reuse; and  
 determining admission of calls received at the receive circuitry based on the loading.  
   
     
     
         8 . The apparatus of  8 , wherein determining admission comprises accepting a new call when the loading is a first value and rejecting a new call when the loading is a second value.  
     
     
         9 . The method of  claim 8 , wherein when the loading the second value, rescheduling the new call.  
     
     
         10 . The method of  claim 7 , wherein the is used to schedule calls within the system.  
     
     
         11 . A computer-readable medium, storing: 
 a first set of instructions for determining frequency reuse of the system;    a second set of instructions for determining loading of the system as a function of the frequency reuse; and    a third set of instructions determining admission of new calls.    
     
     
         12 . A system for monitoring the load on a CDMA communication system, comprising: 
 means for determining frequency reuse of the system;    means for determining loading of the system as a function of the frequency reuse; and    means for determining admission of new calls.