Orthogonal frequency division multiplex (ofdm) receiver with phase noise mitigation and reduced latency

A system for cancelling phase noise in a communication network, said system comprising:

• a platform including a processor, memory coupled to said processor and a user interface coupled to said processor;
• a first receiver coupled to said processor, said first receiver configured to receive OFDM modulated signals from said communication network through a wireless medium, said OFDM modulated signals comprising a current symbol and a sequence of previous symbols, each of said symbols comprising one or more pilot sub-carriers and one or more data sub-carriers;
• a second receiver coupled to said processor, said second receiver configured to receive said OFDM modulated signals from said communication network through a cable medium;
• a phase angle computation circuit coupled to said first and second receivers, said phase angle computation circuit configured to compute a first mean, said first mean computed from the phase angle of one or more of said pilot sub-carriers of a predetermined number of said previous symbols;
• a predictive filter circuit coupled to said phase angle computation circuit, said predictive filter circuit configured to compute a second mean, said second mean estimating the phase angle of one or more sub-carriers of said current symbol, said estimation based on said first mean;
• and
• a phase noise cancelling circuit coupled to said predictive filter circuit, said phase noise cancelling circuit configured to correct the phase of one or more sub-carriers of said current symbol based on said second mean.

A method for cancelling phase noise in an OFDM modulated received signal, said method comprising:

• receiving an OFDM modulated signal comprising a current symbol and a sequence of previous symbols, each of said symbols comprising one or more pilot sub-carriers and one or more data sub-carriers;
• computing a first mean of the phase angles of one or more of said pilot sub-carriers of a predetermined number of said previous symbols;
• computing a second mean to estimate the phase angle of one or more sub-carriers of said current symbol, said estimation performed by a predictive filter based on said first mean;
• and
• correcting the phase of one or more sub-carriers of said current symbol based on said second mean.

A computer-readable storage medium having instructions stored thereon which when executed by a processor result in the following operations for cancelling phase noise in an OFDM modulated received signal, said operations comprising:

• receiving an OFDM modulated signal comprising a current symbol and a sequence of previous symbols, each of said symbols comprising one or more pilot sub-carriers and one or more data sub-carriers;
• computing a first mean of the phase angles of one or more of said pilot sub-carriers of a predetermined number of said previous symbols;
• computing a second mean to estimate the phase angle of one or more sub-carriers of said current symbol, said estimation performed by a predictive filter based on said first mean;
• and
• correcting the phase of one or more sub-carriers of said current symbol based on said second mean.