Method and system of channel analysis and carrier selection in OFDM and multi-carrier systems

Abstract

The invention presents a novel method to channel estimation in OFDM systems. The embodiment of this invention is a block of new logic and modifications performed to other components of the system, added to any existing OFDM receiver, which utilizes information available from other blocks as found in the receiver. This logic would improve the units' error rate because of the improved channel quality estimations it makes available. This improvement is made possible because both channel noise data and channel signal data are used in the estimation process. This data goes through a learning process over time and multiple data blocks for further improvements in the quality of the estimate. This improvement is possible without any direct communications with other remote units, but it could be used in a multi-node environment to improve the performance of the system as the whole.

What is claimed:  
     
         1 . An orthogonal frequency division multiplexing receiving system comprising: 
 a noise analysis logic unit (NAL) for receiving FFT data including at least one of channel noise data and channel signal data, wherein the channel signal data is transmitted on a channel by a transmitter,    wherein the NAL includes inputs for receiving protocol data and predetermined synchronization data, and    wherein the NAL processes the FFT data to identify channel noise data and channel signal data based on the protocol data and the synchronization data.    
     
     
         2 . The system according to  claim 1 , wherein the NAL is coupled to a data processing block which processes the received signal and noise data to identify and provide for learning of noise characteristics of the channel and to generate an enhanced channel quality estimate, providing for an improved error rate for data transmission on the channel.  
     
     
         3 . The system according to  claim 1 , further comprising: 
 at least one carrier selection device which utilizes the enhanced channel quality estimate to select a channel for data signal exchange.    
     
     
         4 . The system according to  claim 1 , further comprising: 
 again control device which utilizes the enhanced channel quality estimate to control signal gain processing.    
     
     
         5 . The system according to  claim 1 , further comprising: 
 a data signal synchronization device which utilizes the enhanced channel quality estimate as part of synchronization processing.    
     
     
         6 . The system according to  claim 1 , further including a distributed intelligence built into a plurality of nodes that allows the system to process the information collected from all nodes to optimize the operation of the system.  
     
     
         7 . The system according to  claim 3 , further including a waiting factor to the at least one carrier to improve the accuracy of synchronization.  
     
     
         8 . A method for providing an orthogonal frequency division multiplexing receiving system comprising the steps of: 
 providing a noise analysis logic unit (NAL) for receiving FFT data including at least one of channel noise data and channel signal data, wherein the channel signal data is transmitted on a channel by a transmitter, and wherein the NAL includes inputs for receiving protocol data and predetermined synchronization data, and further, wherein the NAL processes the FFT data to identify channel noise data and channel signal data based on the protocol data and the synchronization data.    
     
     
         9 . The method according to  claim 8 , further comprising the step of providing silent interval data to derive channel quality assessment data.  
     
     
         10 . The method according to  claim 8 , wherein the noise data are utilized to detect the presence further narrow-band signals.  
     
     
         11 . The method according to  claim 8 , further comprising the step of utilizing the noise data to detect the presence of a wide-band signals.  
     
     
         12 . The method according to  claim 8 , further comprising the step of utilizing the noise data to select carriers for the pilot tone insertion.  
     
     
         13 . The method according to  claim 8 , further comprising the step of exchanging data gathered among all nodes.  
     
     
         14 . The method according to  claim 13 , further providing a dedicated node to process the information collected from all nodes to optimize the operation of the system.  
     
     
         15 . The method according to  claim 8 , further comprising the step of including a distributed intelligence built into a plurality of nodes that allows the processing of the information collected from all nodes to optimize the operation of the system.