Probabilistic model for a positioning technique

Abstract

A model construction module for constructing a probabilistic model of a wireless environment in which a target device communicates using signals that have a measurable signal value, such as signal strength. The model construction module forms several submodels of the wireless environment. Each submodel indicates a probability distribution for signal values at one or more locations in the wireless environment. The module combines the submodels to a probabilistic model of the wireless environment, such that the probabilistic model indicates a probability distribution for signal values at several locations in the wireless environment. Alternatively, the model may insert new locations to a single model based on a combination of existing locations. The combination of submodels or existing locations includes combining the inverse cumulative distribution functions of the submodels or existing locations.

1 . A model construction module for constructing a probabilistic model of a wireless environment in which a target device is operable to communicate using signals each of which has at least one measurable signal value; the model construction module comprising: 
 a first software code portion for forming a plurality of submodels of the wireless environment, each submodel indicating a probability distribution for signal values at one or more locations in the wireless environment; and    for a second software code portion for combining the submodels to a probabilistic model of the wireless environment, the probabilistic model indicating a probability distribution for signal values at several locations in the wireless environment.    
   
   
       2 . A model construction module according to  claim 1 , wherein the at least one measurable signal value comprises bit error rate or ratio.  
   
   
       3 . A model construction module according to  claim 1 , further comprising means for combining weighted probability distributions of the submodels.  
   
   
       4 . A model construction module for constructing a probabilistic model of a wireless environment in which a target device is operable to communicate using signals each of which has at least one measurable signal value; 
 the model construction module comprising:    a first software code portion for forming probabilistic model of the wireless environment, the probabilistic model indicating a probability distribution for signal values at several locations in the wireless environment; a second software code portion for inserting into the probabilistic model a probability distribution for a new location, wherein the inserting step comprises combining probability distributions for existing locations.    
   
   
       5 . A model construction module according  claim 4 , wherein the at least one measurable signal value comprises bit error rate or ratio.