Method of widely linear turbo-equalization in a multi-user context and for a multi-channel multi-antenna receiver

A method of turbo-equalization of a received signal comprising an iterative execution of the following steps:

• executing a received signal equalization method using at least one equalizer filter to equalize a signal received by a plurality of antenna elements, said received signal being produced by a transmission of signals by a plurality of transmitters, said method comprising:
• converting the received signal into a frequency domain to obtain a frequency domain signal,
• subtracting from said frequency domain signal an estimate of an intersymbol interference and an interference between users to obtain a complex corrective signal,
• conjoint widely linear filtering said complex corrective signal and a conjugate of the complex corrective signal to obtain an equalized signal,
• converting the equalized signal into a time domain,
• calculating a covariance matrix of the received signal,
• calculating a pseudo-covariance matrix of the received signal at least from a pseudo-covariance of symbols of said transmitted signals, and
• calculating coefficients of said at least one equalizer filter from the covariance matrix and the pseudo-covariance matrix of the received signal;
• the method of turbo-equalization also comprising:
• converting the equalized signals into demodulated bits,
• decoding the demodulated bits, and
• converting the decoded bits into an estimate of a transmitted signal.

A computer program comprising instructions stored on a tangible non-transitory storage medium for executing on a processor a received signal equalization method using at least one equalizer filter to equalize a signal received by a plurality of antenna elements, said received signal being produced by a transmission of signals by a plurality of transmitters, said method comprising:

• converting the received signal into a frequency domain to obtain a frequency domain signal,
• subtracting from said frequency domain signal an estimate of an intersymbol interference and an interference between users to obtain a complex corrective signal,
• conjoint widely linear filtering said complex corrective signal and a conjugate of the
• complex corrective signal to obtain an equalized signal,
• converting the equalized signal into a time domain,
• calculating a covariance matrix of the received signal,
• calculating a pseudo-covariance matrix of the received signal at least from a pseudo-covariance of symbols of said transmitted signals,
• calculating coefficients of said at least one equalizer filter from the covariance matrix and the pseudo-covariance matrix of the received signal.

A receiver including a plurality of antenna elements for receiving a signal transmitted by a plurality of transmitters and a processor configured to execute a received signal equalization method using at least one equalizer filter to equalize a signal received by a plurality of antenna elements, said received signal being produced by a transmission of signals by a plurality of transmitters, said method comprising:

• converting the received signal into a frequency domain to obtain a frequency domain signal,
• subtracting from said frequency domain signal an estimate of an intersymbol interference and an interference between users to obtain a complex corrective signal,
• conjoint widely linear filtering said complex corrective signal and a conjugate of the complex corrective signal to obtain an equalized signal,
• converting the equalized signal into a time domain,
• calculating a covariance matrix of the received signal,
• calculating a pseudo-covariance matrix of the received signal at least from a pseudo-covariance of symbols of said transmitted signals,
• calculating coefficients of said at least one equalizer filter from the covariance matrix and the pseudo-covariance matrix of the received signal.