Career

The history of cellular phone technology began on December 11, 1947 with an internal memo written by Ring in which he proposed development of a cellular telephone system by American Telephone & Telegraph Company. Although Martin Cooper of Motorola is considered the inventor of the first handheld cellular telephone and the first person to demonstrate to reporters a handheld cell phone call, Cooper"s April 1973 call used cellular telephone technology invented and developed by Bell Labs engineers. Patents of Ring United States. Patent 2,025,400 -- Volume Control Circuits", filed May 26, 1934 United States. Patent 2,165,509 -- Oscillation Generator, filed April 22, 1938 United States. Patent 2,225,928 -- Multiple Unit Steerable Antenna System, filed July 14, 1939 United States. Patent 2,406,402 -- Frequency Adjustment of Resonant Cavities, filed September 3, 1941 United States. Patent 2,410,838 -- Microwave Coupling System, filed March 26, 1942 United States. Patent 2,425,345 -- Microwave Transmission System, filed December 23, 1942 United States. Patent 2,633,492 -- Guided Wave Frequency Range, filed December 30, 1948 United States. Patent 2,629,782 -- Reduction of Phase Distortion, filed August 20, 1949 United States. Patent 2,639,326 -- Microwave Frequency Structure Using Hybrid Junctions, filed March 6, 1951 United States. Patent 2,629,772 -- Reduction of Phase Distortion, filed September 21, 1951 United States. Patent 2,775,700 -- Frequency Stabilized Oscillator", filed October 1, 1953 United States. Patent 3,032,723 -- High Speed Microwave Switching Networks, filed May 31, 1960.