Inter-cell interference and frequency reuse

Reuse-1 and Cell Edge Interference

5G NR uses frequency reuse factor of 1 — every cell uses the entire bandwidth. This maximizes spectral efficiency but creates co-channel interference at cell boundaries where signals from adjacent cells overlap. Cell edge SINR can drop to -5 to 0 dB, limiting throughput to QPSK or low-order modulation. Traditional mitigation includes ICIC (frequency-domain partitioning at cell edges) and eICIC (time-domain Almost Blank Subframes for macro/small cell coordination). However, the most powerful 5G-specific tool is massive MIMO beam-based interference management.