Calculating Phase Noise Margins for Industrial Wi-Fi Seven Modules Operating near Arc Welders
Phase noise margin calculations near arc welders demand adding reciprocal mixing degradation figures directly to local oscillator phase noise floors.
Power Line Transient Ripple
Meaning
Fluctuations in the supply voltage of an electronic circuit can introduce noise and instability into sensitive system components. Excessive power line transient ripple often results from the switching of nearby power regulators or high load devices.
Supply Stability
Maintaining a constant DC level is essential for the reliable operation of precision analog and digital circuits. When power line transient ripple exceeds the tolerance of a module, it can cause errors in frequency synthesis or data conversion. Designing for low noise at the power input ensures that the system can handle sudden changes in current demand.
Component Response
Sensitive radio frequency frontends are particularly susceptible to performance degradation from power supply noise. If the power line transient ripple is not properly filtered, it can modulate the output of a local oscillator and create unwanted sidebands. Sensitive components require dedicated voltage regulators to maintain a stable operating point despite fluctuations on the main power rail.
Filtering Technique
Passive components such as inductors and low equivalence series resistance capacitors are used to attenuate high frequency noise. Placing these filters close to the device power pins provides the most effective protection against power line transient ripple. A combination of bulk storage and high frequency decoupling is necessary to cover a wide range of noise frequencies.