Clock Spur Suppression in Phased-Array RF Subsystems (Download)
In high-performance RF systems, maintaining exceptional signal purity is essential to ensure accurate signal representation and optimal dynamic range. Clock spurs — unwanted tones resulting from clock leakage or coupling into sensitive analog signal paths — pose a significant threat to system performance. These spurious components can elevate the noise floor, reduce spurious-free dynamic range (SFDR), and compromise overall signal integrity, particularly in direct-RF-sampling architectures where clock and data domains are tightly integrated.
Within the Quad-Apollo MxFE platform, detailed signal-integrity analysis revealed that clock spurs originated from the ADF4382 ICs, with radiative coupling mechanisms introducing periodic interference into the DAC output traces. Such coupling not only produced coherent spectral artifacts, but it also affected system-level linearity and multichannel synchronization.