ABSTRACT In order to reduce the massive computational overload at the central processing unit in the intelligent reflecting surface (IRS)‐aided cell‐free (CF) massive multiple‐input multiple‐output (m‐MIMO) systems, multiple local processing units (LPUs) are introduced in this letter for uplink signal detection. The analytical closed‐form expressions for the bit error rate (BER) and achievable sum spectral efficiency (ASSE) obtained by the zero‐forcing decoder in uplink IRS‐aided CF m‐MIMO systems with LPUs are derived, and the corresponding computational complexity (CC) is further analysed. The simulation results validate their correctness. Compared to the single IRS aided uplink m‐MIMO systems composed of centralized base station with receive correlation, the CF architecture incorporating LPUs demonstrates significantly superior performance in terms of both improved BER and ASSE characteristics with substantially reduced CC.
Li et al. (Thu,) studied this question.