Happy Friday, everyone.

As wireless systems—from 5G and satellite communications to tactical radios—push into the millimeter-wave and other high-frequency domains, the demands on performance are rising fast. These systems need to tune across wider bandwidths, handle more complex waveforms with advanced modulation schemes, and operate in faster tuning modes. That means their frequency sources—especially local oscillators (LOs)—must also move higher in frequency and deliver significantly lower phase noise.

Direct synthesizers still set the performance benchmark. But it's the more compact, cost-effective designs based on phase-locked loops (PLLs) that are increasingly stepping up to meet the challenge. In today’s top story, analog expert Frederick Weist digs into the details of designing very wide loop bandwidth PLLs. Check out Parts 1 and 2 of his feature, and stay tuned for the final installment in the near future.

-James Morra, Senior Editor