Contention-based access to tones in orthogonal frequency division multiplexing (ofdm) waveform

Abstract

A multiple access method for a remote unit of a multi-point to point communication system is provided. The method includes modulating one or more tones of an orthogonal frequency division multiplexing waveform with the upstream information based on an inverse Fourier transform algorithm, transmitting the one or more tones to a multi-point-to-point host unit, detecting a collision of the one or more tones, and when a collision is detected, re-transmitting the one or more tones.

1 . A multiple access method for a remote unit of a multi-point to point communication system, the method comprising: 
 modulating one or more tones of an orthogonal frequency division multiplexing waveform with the upstream information based on an inverse Fourier transform algorithm;    transmitting the one or more tones to a multi-point-to-point host unit;    detecting a collision of the one or more tones; and    when a collision is detected, re-transmitting the one or more tones.    
     
     
         2 . The method of  claim 1 , wherein re-transmitting the one or more tones further comprises retransmitting the one or more tones based on a backoff procedure.  
     
     
         3 . The method of  claim 1 , wherein detecting a collision of the one or more tones further comprises detecting a potential collision based on a signal from the multipoint-to-point host.  
     
     
         4 . The method of  claim 1 , wherein transmitting the one or more tones to a multi-point-to-point host unit further comprises transmitting the one or more tones over a distribution network comprising a wireless system.  
     
     
         5 . A method for multiple access to a host unit of a multi-point to point communication system, the method comprising: 
 receiving an orthogonal frequency division multiplexing waveform from one or more remote units of a plurality of remote units, the orthogonal frequency division multiplexing waveform having a plurality of tones;    demodulating upstream information from the plurality of tones based on a Fourier transform algorithm; and    transmitting a message to at least one of the plurality of remote units when a collision is detected in the orthogonal frequency division multiplexing waveform.    
     
     
         6 . The method of  claim 5 , wherein receiving an orthogonal frequency division multiplexing waveform further comprises receiving the orthogonal frequency division multiplexing waveform over a distribution network comprising a wireless system.  
     
     
         7 . A method for a multiple access bi-directional communication system, the method comprising: 
 establishing communication between a first remote unit of a plurality of remote units and a host unit, the plurality of remote units communicatively coupled to the host unit in a multipoint-to-point configuration;    receiving up to a plurality of tones at the host unit from the first remote unit, the up to a plurality of tones modulated with upstream information using orthogonal frequency division multiplexing;    detecting a potential collision between the up to a plurality of tones transmitted from the first remote unit and any tones transmitted within the orthogonal frequency division multiplexing waveform by another remote unit of the plurality of remote units.    
     
     
         8 . The method of  claim 7 , further comprising: 
 re-transmitting the up to a plurality of tones when the potential collision is detected.    
     
     
         9 . The method of  claim 7 , further comprising: 
 re-transmitting the up to a plurality of tones based on a back-off procedure when the potential collision is detected    
     
     
         10 . The method of  claim 7  further comprising: 
 transmitting a signal from the host unit indicating whether the host unit successfully receives the upstream information.    
     
     
         11 . The method of  claim 7 , wherein receiving up to a plurality of tones at the host unit comprises receiving up to a plurality of tones over a wireless system.