Method of joint user activity detection and channel information estimation in extra-large mimo (xl-mimo) systems with non-stationarities

A receiver of a communication system having a processor, volatile and/or non-volatile memory, at least one interface adapted to receive a signal in a communication channel, wherein the non-volatile memory stores computer program instructions which, when executed by the microprocessor, configure the receiver to perform operations comprising:

• receiving signals and initialization of a channel estimation;
• performing a soft interference cancel check, whereby, if the soft interference cancel check result is negative, the calculation of residual mean and variance is performed and whereby, if the soft interference cancel check result is positive, the extrinsic mean and variance is calculated directly;
• calculating the extrinsic mean and variance, whereby, if the soft interference cancel check result is negative, the calculation of residual mean and variance is used;
• calculating tentative estimates, whereby the calculation of tentative estimation includes activity factors calculation;
• determining whether a condition of reaching a maximum is fulfilled whereby, if the condition of reaching the maximum fulfilled check result is negative, soft interference cancel check is performed and whereby, if the condition of reaching the maximum fulfilled check result is positive, performance of the operations ends.