Method and system for determining and removing DC offset in communication signals

• Main Author: HALL STEVEN D
• Format: Patent
• Language: English
• Published: 08.05.2012
• Subjects: ELECTRIC COMMUNICATION TECHNIQUE; ELECTRICITY; TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHICCOMMUNICATION

According to one exemplary embodiment, a method and system for determining and removing DC offset in an AC signal includes receiving an AC signal having a first-channel and a second-channel, e.g. an I-channel and a Q-channel, receiving a plurality of first-channel and second-channel samples, storing a negative first-channel sample corresponding to a first sign change in the plurality of second-channel samples, and storing a positive first-channel sample corresponding to a second sign change in the plurality of second-channel samples. The method further includes determining an average value of the negative first-channel sample and the positive first-channel sample, where the average value is the DC offset in the first-channel. The method can further include subtracting the determined DC offset from samples received in the first-channel (or the second-channel) prior to demodulation. The method and system can be implemented in, for example, a Bluetooth receiver.