DC interference removal in wireless communications

A method for removing direct current (DC) interference from a received signal, the method comprising:

• operating on an equal number of positive and negative Barker chips to determine a sum of the DC offset estimate;
• dividing the sum by the number of Barker chips to form an estimate of the DC offset signal;
• and
• removing the DC estimate from a remaining chip term to produce a at least a first part of a Barker de-spread output with the DC offset signal removed.

A communication receiver comprising:

• a detection component configured to remove receiver induced direct current (DC) offset interference from a received signal;
• a timing and carrier offset correction component coupled to the detection component;
• a symbol recovery component coupled to the timing and carrier offset correction component, the symbol recover component configured to estimate a transmitted symbol by examining a frequency corrected signal with estimated transmitter-induced DC offset interference removed;
• and
• a transmitter DC estimation component coupled to the symbol recovery component, the transmitter DC estimation component configured to receive the estimated transmitted symbol and subtract the symbol to produce an estimate of the transmitter-induced DC offset interference.

A system for removing direct current (DC) interference from one or more signals received by a communication receiver, the system comprising:

• means for estimating a DC offset signal induced by the communication receiver;
• means for removing the estimated DC offset from the received signal;
• means for correcting a frequency shift in the received signal;
• means for estimating a second DC offset signal induced by a source of the received signal;
• and
• means for removing the estimated second DC offset from the received signal;
• wherein the means for removing direct current (DC) interference from a received signal includes (a) means for operating on an equal number of positive and negative Barker chips to determine a sum of the DC offset estimate, (b) means for dividing the sum by the number of Barker chips to form an estimate of the DC offset signal, and (c) means for removing the DC estimate from a remaining chip term to produce a at least a first part of a Barker de-spread output with the DC offset signal removed.

A method for determining a direct current (DC) offset signal in a received symbol in a wireless communication system, the method comprising:

• determining a sum of chips in the received symbol, the received symbol according to a complementary code keying (CCK) code;
• and
• isolating the DC offset signal by method as determined by the sum of the chips by (a) identifying one of a plurality of groups to which the received symbol belongs according to the sum of the chips;
• and (b) applying a function according to the identified group.