Barrie Gilbert (born June 5th 1937 in Bournemouth, England, died January 30th 2020) was an English-American inventor. He was well known for his invention of numerous analog circuit concepts, holding over 100 patents worldwide, and for the discovery of the Translinear Principle. His name is attributed to a class of related topologies loosely referred to as the Gilbert cell, one of which is a mixer - a key frequency translation device - used in every modern wireless communication device. A similar topology, for use as a synchronous demodulator, was invented by Howard Jones in 1963. During the 1950s he pursued an interest in solid-state devices while at Mullard, working on the development of early transistors, and later, the first-generation planar ICs. After some pioneering development of sampling oscillography he emigrated to the United States in 1964 to pursue this interest at Tektronix, Beaverton, Oregon, where he developed the first electronic knob-readout system and other advances in instrumentation. He returned to England in 1970, where he was Group Leader at Plessey Research Laboratories, managing a team developing OCR systems and integrated circuits (ICs) for communications applications. From 1972-1977 he consulted for Analog Devices Inc., Beaverton, OR, designing several ICs embodying novel nonlinear concepts. He returned to the USA and Tektronix in 1977 to pursue HF ICs and process development.