Methods, systems, and devices for wireless communications are described. Some wireless communications systems may utilize beamforming techniques to process wireless communications transmitted in millimeter wave (mmW) frequency ranges. In such cases, a user equipment (UE) may perform lattice reduction (LR)-based preprocessing for a received resource element (RE), which allows the UE to utilize demapping techniques (e.g., minimum mean square error (MMSE)-based demapping techniques or successive interference cancellation (SIC) demapping techniques) that are less computationally-complex than conventional demapping techniques (e.g., maximum likelihood (ML)-based demapping techniques) while providing a similar performance as conventional techniques. Further, due to mmW systems' robustness to time-dispersion, the UE may apply the same LR to multiple REs across multiple symbols in the time domain and across multiple sub-carriers in the frequency domain. The computational cost of performing the LR calculation may be spread across multiple REs and further increase the efficiency of utilizing low-complexity demapping techniques.