John Walker is currently European Sales Manager at Integra Technologies, Inc. He received his PhD from the University of Leeds in 1976 and has since held various industry positions, including Microwave Hybrids Manager at Thorn-EMI Electronics and RF Division Manager at Semelab. He is the editor and co-author of the books High Power GaAs FET Amplifiers and Classic Works in RF Engineering. He is a Fellow of the IEE.