Digital I/q Imbalance Compensation in a Low-if Receiver
نویسنده
چکیده
Double) Low-IF receiver architectures avoid the need for expensive image-reject and channel selection filters and so reduce cost. This approach however introduces the need for an accurate in-phase and quadrature version of the first local oscillator. In this document we present a way to digitally measure amplitude and phase imbalances and compensate for them. Simulations show image-reject values round 50 dB with amplitude imbalances of more than 10% and phase imbalances of more than 10 degrees. Although we focus on GSM-like applications, the algorithms are suitable for other Low-IF systems as well.
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