GreenPeak describes itself as a leader in battery-free communication technology for wireless sense and control applications. Its technology uses energy-harvesting to facilitate battery-free operation in a totally wireless environment, without the need for either communications or power connectivity.See http://www.greenpeak.com
Agilent Technologies
Analog Devices
Harting
LEM
Maxim Integrated Products
NXP
Rohde & Schwarz
Tektronix
Toshiba
Yokogawa