What is the interference paradox in wireless networks?

When experiencing high interference, a device can increase its transmit power to improve its own SNR — but this increases interference for everyone else, potentially triggering a chain reaction.

* The interference paradox: a positive-feedback power race. *

The paradox:

1. Device A experiences interference and increases its transmit power
2. This improves A's SNR → A's connection gets better
3. But A's stronger signal now causes more interference for nearby devices B and C
4. B and C may also increase their power to compensate
5. This creates a positive feedback loop (Aufschaukeleffekt) where everyone keeps raising power

Sources of interference:

• Other radio sources on the same frequency band (other WLANs, Bluetooth)
• A classic example: a 2.4 GHz mobile phone interfering with 802.11b Wi-Fi
• Electromagnetic noise from household appliances (microwave ovens operate at ~2.45 GHz)

Real-world solution: This is why standards like LTE and 5G include power control mechanisms — the network tells each device exactly how much power to use, preventing this arms race. Wi-Fi uses a different approach: listen-before-talk (carrier sense) to avoid transmitting when others are active.

Go deeper:

• Power control (Wikipedia) — the transmit-power-control mechanism that prevents the power arms race.
• Near–far problem (Wikipedia) — the positive-feedback escalation where everyone boosting power defeats itself.