Every radio wave obeys v = f·λ (v = c, the speed of light), so a higher carrier frequency f means a shorter wavelength λ. Massive MIMO arrays combine many antenna elements (N) so their signals add up constructively in one chosen direction and cancel out elsewhere — a narrow, steerable beam instead of a broadcast in all directions. More elements give a narrower beam and more gain: beamwidth ≈ 101.5° / N. mmWave bands (24–40 GHz+) carry far more bandwidth than Sub-6 GHz, but their short wavelength is absorbed and blocked more easily, so usable range is shorter — the classic 5G speed-vs-range trade-off shown here by the beam's reach and by devices dropping connection outside the highlighted sector.