 This equipment was also produced under license in Poznań (Poland), and in Yugoslavia, and elsewhere.ITT was the largest owner of the LM Ericsson company in Sweden but sold out in 1960.Alec Reeves invented pulse-code modulation (PCM), upon which future digital voice communication was based, and Charles K. Kao pioneered the use of optical fiber, for which he was awarded the 2009 Nobel Prize in Physics.