Since a current GSM base station determines whether a terminal can remove interference using only a DARP information report of the terminal, the base station itself needs to determine whether the terminal is a VAMOS-executable terminal that can perform an interference removal function. The base station transmits a signal, together with a signal acting as interference, using an A-QPSK method, in order to determine whether the terminal can use a VAMOS function, and determines whether the terminal can receive an A-QPSK symbol, in consideration of a reception quality signal of a signal transmitted by the terminal.

Aspects relate to correcting Inphase/Quadrature (I/Q) imbalances across multiple wireless elements such as multiple receive elements or multiple transmit elements. In one example implementation, I/Q imbalances can be corrected using a digital circuit provided within a digital portion of a direct conversion wireless element (upconversion or downconversion) that implements only two multiplications and one addition per pair of I and Q samples.

An apparatus for correcting a deviation between a plurality of transmission channels includes a first transmission channel and a second transmission channel. The apparatus also includes a phase offset unit configured to set a phase offset between the first transmission channel and the second transmission channel such that a phase deviation between the first transmission channel and the second transmission channel deviates from zero, a power detection unit configured to detect signal powers of the first transmission channel and the second transmission channel under the phase offset, a processing unit configured to determine, based on the detected signal powers, a deviation correction value between the first transmission channel and the second transmission channel, where the deviation correction value includes a phase correction value, and a phase correction unit configured to set the phase correction value between the first transmission channel and the second transmission channel.

An apparatus for correcting a deviation between a plurality of transmission channels includes a first transmission channel and a second transmission channel. The apparatus also includes a phase offset unit configured to set a phase offset between the first transmission channel and the second transmission channel such that a phase deviation between the first transmission channel and the second transmission channel deviates from zero, a power detection unit configured to detect signal powers of the first transmission channel and the second transmission channel under the phase offset, a processing unit configured to determine, based on the detected signal powers, a deviation correction value between the first transmission channel and the second transmission channel, where the deviation correction value includes a phase correction value, and a phase correction unit configured to set the phase correction value between the first transmission channel and the second transmission channel.

An input signal has a desired signal component and an interfering signal component superimposed thereon. Interfering component estimation processing is applied to the input signal, obtaining as a result a filtered signal comprising a sequence of filtered data samples. The filtered signal is subtracted from the input signal obtaining as a result an output signal comprising a sequence of output data samples. The interfering component estimation processing applies conjugating processing to the input signal, providing a conjugated version of the input signal. An adaptive signal processing coefficient is computed and adaptive signal processing is applied to the conjugated version of the input signal using the adaptive processing coefficient.

An apparatus includes a phase offset unit configured to set a phase offset between the first transmission channel and the second transmission channel such that a phase deviation between the first transmission channel and the second transmission channel deviates from zero, a power detection unit configured to detect signal powers of the first transmission channel and the second transmission channel under the phase offset, a processing unit configured to determine, based on the detected signal powers, a deviation correction value between the first transmission channel and the second transmission channel, where the deviation correction value includes a phase correction value, and a phase correction unit configured to set the phase correction value between the first transmission channel and the second transmission channel.

An input signal has a desired signal component and an interfering signal component superimposed thereon. Interfering component estimation processing is applied to the input signal, obtaining as a result a filtered signal comprising a sequence of filtered data samples. The filtered signal is subtracted from the input signal obtaining as a result an output signal comprising a sequence of output data samples. The interfering component estimation processing applies conjugating processing to the input signal, providing a conjugated version of the input signal. An adaptive signal processing coefficient is computed and adaptive signal processing is applied to the conjugated version of the input signal using the adaptive processing coefficient.

The embodiments described herein provide systems and methods for digital correction in low intermediate frequency (IF) receivers. Specifically, the embodiments described herein use digital correction techniques that can correct for signal distortions in low IF receivers caused by I-Q imbalance, including both I-Q magnitude imbalance and I-Q phase imbalance. In general, the embodiments described herein are implemented to at least partially cancel an image of a blocking signal in the complex digital signal. Such a cancellation can be implemented to at least partially cancel an image of blocking signal where that image occurs at or near the intermediate frequency. In one embodiment, a corrector is implemented in a low RF receiver and is configured to receive a complex digital signal that includes an image of a blocking signal. Such a low RF receiver can further include a trainer configured to train the corrector to generate the cancellation signal.

The embodiments described herein provide systems and methods for digital correction in low intermediate frequency (IF) receivers. Specifically, the embodiments described herein use digital correction techniques that can correct for signal distortions in low IF receivers caused by I-Q imbalance, including both I-Q magnitude imbalance and I-Q phase imbalance. In general, the embodiments described herein are implemented to at least partially cancel an image of a blocking signal in the complex digital signal. Such a cancellation can be implemented to at least partially cancel an image of blocking signal where that image occurs at or near the intermediate frequency. In one embodiment, a corrector is implemented in a low RF receiver and is configured to receive a complex digital signal that includes an image of a blocking signal. Such a low RF receiver can further include a corrector controller to selectively enable the corrector.

An apparatus includes a phase offset unit configured to set a phase offset between the first transmission channel and the second transmission channel such that a phase deviation between the first transmission channel and the second transmission channel deviates from zero, a power detection unit configured to detect signal powers of the first transmission channel and the second transmission channel under the phase offset, a processing unit configured to determine, based on the detected signal powers, a deviation correction value between the first transmission channel and the second transmission channel, where the deviation correction value includes a phase correction value, and a phase correction unit configured to set the phase correction value between the first transmission channel and the second transmission channel.