AdjacentChannelInterferenzen

AdjacentChannelInterferenzen, also known as adjacent channel interference (ACI), is a form of radio-frequency interference that occurs when energy from a transmitter leaks into a neighboring channel, degrading reception on that channel. It is most common in systems that rely on tightly spaced channels or where emissions masks are not strictly enforced.

Causes include inadequate transmitter filtering, poor receiver selectivity, and spectral leakage from high-power transmitters. Nonlinearities in amplification, improper filter design, and shared spectrum in dense deployments also contribute. Environmental factors such as multipath, reflection, and interference from powerful nearby services can exacerbate the problem.

Effects vary by application but typically include reduced signal-to-noise ratio, audible distortion in audio services, data errors, slower throughput, or dropped connections. In digital systems these effects can appear as increased bit error rates or link outages.

Measurement and regulation: ACI is assessed using metrics like Adjacent Channel Leakage Ratio (ACLR) or adjacent-channel suppression, comparing the power in an adjacent channel to the power within the intended channel. Regulatory bodies impose spectral masks and minimum channel spacing to limit ACI and require devices to meet emissions limits.

Mitigation: Solutions include stricter spectral masking, wider guard bands, better RF filtering at transmitter and receiver, careful power control, and thoughtful network planning and frequency reuse strategies. In dynamic spectrum environments, adaptive techniques can help minimize interference between neighboring channels.

Applications: ACI is relevant across broadcast, cellular, Wi-Fi, and other wireless services, where tight channel plans and coexistence requirements demand attention to adjacent channel emissions.