John Cowles

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We present a 16-element hybrid grid amplifier. This is the first successful grid amplifier to use a reflection architecture, which should provide thermal performance superior to transmission grids. The grid uses custom-made differential-pair chips with TRW InP Heterojunction Bipolar Transistors (HBTs) as the active devices. We measure a peak gain of 15 dB(More)
Many complex physical systems such as biological, ecological, and other natural systems are characterized both by incomplete models and limited empirical data. Accurate prediction of the behavior of such systems requires exploitation of multiple, individually incomplete, knowledge sources. This dissertation describes model-based adaptation, a technique for(More)
As wireless communication systems evolve toward higher frequencies, higher bandwidths, and multi-standard capabilities, the performance of their phase-locked loops (PLLs) becomes increasingly critical to overall system performance. Additionally, PLLs often must be integrated with large digital blocks, so there is strong and increasing economic pressure to(More)
Stipulations on the correctness of proofs produced in a formal system include that the axioms and proof rules are the intended ones and that the proof has been properly constructed (i.e. it is a correct instantiation of the axioms and proof rules.) In software implementations of formal systems, correctness additionally depends both on the correctness of the(More)
MULTIPLIERS Some 33 years ago, we noted the introduction of the AD530—the world's first complete analog multiplier-on-a-chip—with a rambling historical discourse appropriately dubbed, " Multiplier Memories and Meanderings. " Eighteen years later, with many successful generations of multipliers (and a growing family of other translinear devices) in our(More)
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