Wireless terminal methods and apparatus for DC tone special treatment
Special DC tone treatment in a wireless communications system, e.g., an OFDM system, is discussed. In the downlink, a wireless terminal receiver introduces self-interference at the DC tone from the RF/baseband conversion. A base station every so often does not transmit on the downlink DC tone while continuing to transmit on other downlink tones. Wireless terminals measure received signal on the downlink DC tone during the time of suspended DC tone transmission, estimate self-interference and apply a correction to other received downlink DC tones. In the uplink DC tone interference is a composite of the assigned wireless terminal transmitter's baseband/RF conversion self-interference and air link noise. During one symbol interval of an N symbol interval dwell, the uplink DC tone is reserved for a special modulation symbol, which is a predetermined function of the other N−1 modulation symbols. At the base station, its receiver receives a set of modulation symbols conveyed by the uplink DC tone for a dwell, calculates the average DC component and corrects the received N−1 modulation symbols.
QUALCOMM Incorporated
H H H
H04B H04L H04L
inventional inventional inventional
Junyi Rajiv Hui
Li Laroia Jin