Image rejection compensation method for I/Q down-conversion in radio frequency receivers, corresponding circuit, radio frequency receiver device and computer program product

A circuit, comprising:

• an input node configured to receive an input signal comprising at least one sequence of input data samples, the input signal comprising a desired signal component and an interfering signal component superimposed thereon, wherein input data samples in the sequence of input data samples are separated by a sampling period therebetween;
• and
• signal processing circuitry coupled to the input node, wherein the signal processing circuitry, in operation:
• applies interfering component estimation processing to said input signal obtaining as a result a filtered signal comprising a sequence of filtered data samples;
• and
• subtracts said filtered signal from said input signal, obtaining an output signal comprising a sequence of output data samples,
• wherein said interfering component estimation processing comprises:
• applying conjugating processing to said input signal, providing a conjugated version of said input signal;
• computing one or more adaptive signal processing coefficients;
• and
• applying adaptive signal processing to said conjugated version of said input signal using the one or more adaptive signal processing coefficients,
• wherein said computing the one or more adaptive signal processing coefficients comprises:
• performing correlation processing between said sequence of output data samples of the output signal and a conjugated version of said sequence of output data samples of the output signal, obtaining a sequence of estimates of residual correlation;
• and
• applying integration processing to said sequence of estimates of residual correlation, said integration processing using an integration step parameter and at least one starting point parameter, obtaining the one or more adaptive signal processing coefficients.

A radio-frequency receiver, comprising:

• an antenna configured to receive an RF signal;
• a radio frequency front-end coupled to said antenna, the radio frequency front-end configured to receive said RF signal at an input node and to apply down-conversion processing to said radio frequency signal, the radio frequency front-end having a first output node and configured for providing an intermediate frequency, IF, signal as a result of said down-conversion processing at said first output node;
• an analog-to-digital converter, ADC, having an input node coupled to said first output node and a second output node, the ADC configured to receive said IF signal from the first output node, to apply signal sampling thereto and to provide a sampled sequence of data samples of said IF signal at said second output node;
• and
• signal processing circuitry coupled to the second output node, wherein the signal processing circuitry, in operation:
• applies interfering component estimation processing to an input signal, obtaining a filtered signal comprising a sequence of filtered data samples;
• and
• subtracts said filtered signal from said input signal, obtaining an output signal comprising a sequence of output data samples,
• wherein said interfering component estimation processing comprises:
• applying conjugating processing to said input signal, generating a conjugated version of said input signal;
• computing an adaptive signal processing coefficient;
• and
• applying adaptive signal processing to said conjugated version of said input signal using the adaptive signal processing coefficient,
• wherein computing the adaptive signal processing coefficient comprises:
• performing correlation processing between said sequence of output data samples of the output signal and a conjugated version of said sequence of output data samples of the output signal, obtaining a sequence of estimates of residual correlation;
• and
• applying integration processing to said sequence of estimates of residual correlation, said integration processing using an integration step parameter and at least one starting point parameter, obtaining the adaptive signal processing coefficient.

A non-transitory computer-readable medium having contents which configure a receiver to perform a method, the method comprising:

• applying interfering component estimation processing to an input signal, obtaining a filtered signal comprising a sequence of filtered data samples;
• and
• subtracting the filtered signal from the input signal, obtaining an output signal comprising a sequence of output data samples,
• wherein the interfering component estimation processing comprises:
• applying conjugating processing to said input signal, generating a conjugated version of the input signal;
• computing one or more adaptive signal processing coefficients;
• and
• applying adaptive signal processing to the conjugated version of the input signal using the one or more adaptive signal processing coefficients,
• wherein the computing the adaptive signal processing coefficients comprises:
• performing correlation processing between the sequence of output data samples of the output signal and a conjugated version of the sequence of output data samples of the output signal, obtaining a sequence of estimates of residual correlation;
• and
• applying integration processing to the sequence of estimates of residual correlation, said integration processing using an integration step parameter and at least one starting point parameter, obtaining the adaptive signal processing coefficients.