Wi-Fi & Wireless Systems
How electromagnetic radio frequencies, 1024-QAM modulation, CSMA/CA half-duplex contention, and beamformed MIMO antennas transmit gigabits of data through the air without physical wires.
Pieces in this series
How Wi-Fi Actually Works
Electromagnetic radio waves, 2.4/5/6 GHz channels, CSMA/CA collision avoidance, and orthogonal frequency division multiplexing
Wi-Fi does not broadcast continuous streams of light or mystical internet fog. It converts digital bits into microscopic phase and amplitude shifts across high-frequency electromagnetic radio waves (2.4 GHz, 5 GHz, and 6 GHz), negotiated…
Why Wi-Fi Gets Worse Through Walls
Dielectric attenuation, skin depth, Fresnel zone obstruction, and dynamic modulation fallback
Wi-Fi signals do not merely weaken with distance; they lose energy exponentially through dielectric absorption, reflection off metallic steel rebar, and diffraction around doorframes. When obstacles degrade signal-to-noise ratio (SNR)…
How Cellular Networks Route Calls and Data
Base station radio schedulers, RRC connection handshakes, inter-cell handovers, GTP tunnels, and VoLTE/5G core architectures
Cellular networks operate on authoritative microsecond-scale centralized scheduling across licensed spectrum. Base stations chop radio channels into millisecond time-frequency resource blocks, coordinating user plane GTP tunnels across…
How Bluetooth Pairs, Frequency Hops, and Transmits Data
From 2.4 GHz ISM interference and adaptive frequency hopping (AFH) to piconet clock synchronization, ECDH pairing, and Bluetooth Low Energy (BLE)
Bluetooth survives in the chaotic 2.4 GHz spectrum through Adaptive Frequency Hopping (AFH)—jumping between 79 distinct radio channels 1,600 times every second. Paired devices synchronize through microscopic clock offsets, negotiate…
How 5G Beamforming and Massive MIMO Transmit Gigabits
From 64T64R active antenna systems and phased-array constructive interference to channel state information (CSI), spatial multiplexing, and millimeter-wave physics
Traditional cell towers broadcast radio waves across a wide 120-degree sector like a floodlight, wasting energy and causing mutual interference. 5G Massive MIMO replaces passive panels with active 64T64R phased-array grids, using digital…