EMZETT.Receiver
In short: In general, a device or component that receives a (radio) signal — in a networking context, e.g. the receiving part of a radio link.
In more detail: The term appears wherever signals are transmitted wirelessly — from Wi-Fi antennas through satellite receivers to Bluetooth devices. The counterpart is always a transmitter; many devices today combine both functions in a transceiver.
In Depth
A receiver takes the physical signal (radio waves, light pulses, electrical voltage) and converts it back into a form usable by the next higher level of processing — this process is called demodulation. The quality of a receiver largely determines how reliably even weak or disturbed signals can still be interpreted correctly, which directly affects the range and error rate of a connection.
In most modern network devices (Wi-Fi cards, smartphones, Bluetooth headphones), the receiver isn’t fitted as a separate component but integrated together with the transmitter in a single chip — a so-called transceiver (transmitter + receiver). This saves space and cost, since transmitting and receiving electronics can share many components (antenna, frequency control).
Sensitivity and signal-to-noise ratio
A key metric for a receiver’s quality is its sensitivity — the weakest signal strength at which it can still reliably distinguish a signal from background noise, stated in dBm (usually a negative value such as -90 dBm; the more negative, the more sensitive/better). What matters is not just the absolute signal strength, but the signal-to-noise ratio (SNR): a strong signal in a very “noisy” radio environment (many overlapping Wi-Fi networks, sources of electromagnetic interference) can still be harder to receive than a weaker signal in a quiet environment.
Diversity reception and MIMO
Modern Wi-Fi receivers often use several antennas at the same time (“MIMO” — multiple input, multiple output) to improve both range and data throughput. Instead of evaluating only a single received signal, the receiver combines the slightly different signals from several antennas to compensate for interference and signal cancellation (which occurs when a signal arrives at the receiver slightly offset in time via several paths, e.g. due to reflections off walls). Routers with “3x3 MIMO” or similar specifications refer to exactly this number of transmit/receive antennas used at the same time.