| 摘要 |
Mechanisms for reducing I/Q impairments in communication devices are described. A transmitter performs pre-correction on digital I/Q signals before converting them into analog I/Q signals, to pre-compensate for I/Q impairments which will subsequently be introduced during digital-to-analog conversion, I/Q modulation, or other processing that occurs to produce a transmission signal. A receiver receives a transmission signal, produces digital I/Q signals from it, and performs filtering on the digital I/Q signals to correct I/Q impairments at a plurality of frequency offsets. Furthermore, mechanisms for measuring transmitter and/or receiver I/Q impairments are disclosed, including iterative methods for measuring transmitter I/Q impairments using shared local oscillators or using intentionally-offset local oscillators, and methods for measuring receiver I/Q impairments. Also disclosed are methods for computing I/Q impairments from a sampled complex signal, for computing DC properties of a signal path between the transmitter and receiver, and for transforming I/Q impairments through a linear system. |
