@article{discovery10195960,
          number = {21},
            year = {2024},
           month = {November},
         journal = {IEEE Internet of Things Journal},
           title = {Block-Level MU-MISO Interference Exploitation Precoding: Optimal Structure and Explicit Duality},
           pages = {35519--35535},
          volume = {11},
            note = {This version is the author-accepted manuscript. For information on re-use, please refer to the publisher's terms and conditions.},
       publisher = {Institute of Electrical and Electronics Engineers (IEEE)},
            issn = {2327-4662},
        keywords = {Precoding, Interference, Symbols, Signal to noise ratio,
Vectors, Optimization, Minimization},
          author = {Yang, Junwen and Li, Ang and Liao, Xuewen and Masouros, Christos and Swindlehurst, A Lee},
             url = {https://doi.org/10.1109/JIOT.2024.3438569},
        abstract = {This paper investigates block-level interference exploitation (IE) precoding for multi-user multiple-input single-output (MU-MISO) downlink systems. To overcome the need for symbol-level IE precoding to frequently update the precoding matrix, we propose to jointly optimize all the precoders or transmit signals within a transmission block. The resultant precoders only need to be updated once per block, and while not necessarily constant over all the symbol slots, we refer to the technique as block-level slot-variant IE precoding. Through a careful examination of the optimal structure and the explicit duality inherent in block-level power minimization (PM) and signal-to-interference-plus-noise ratio (SINR) balancing (SB) problems, we discover that the joint optimization can be decomposed into subproblems with smaller variable sizes. As a step further, we propose block-level slot-invariant IE precoding by adding a structural constraint on the slot-variant IE precoding to maintain a constant precoder throughout the block. A novel linear precoder for IE is further presented, and we prove that the proposed slot-variant and slot-invariant IE precoding share an identical solution when the number of symbol slots does not exceed the number of users. Numerical simulations demonstrate that the proposed precoders achieve a significant complexity reduction compared against benchmark schemes, without sacrificing performance.}
}