Willy Christian Simonsen (*13.09.1913) was a Norwegian enginer and business founder.
After his graduation at the Univertity of Dresden (Germany) in 1938 he worked for 'Elektrisk Bureau', and since 1939 at 'Chr. Michelsen Institute'.
In WWII he was involved in the Norwegian resistance movement. Arrested by the GeStaPo he was soon admitted to to the "Ullevål Hospital" from weher he escaped and fled to England. There he started working in the Radio Production Unit of the British War Office and developed the shortwave radio "Sweetheart" which was manufactured in England from 1942 to 1944 (about 50.000 units).

In 1947 he founded "Simonsen Radio A/S" in Oslo. The brand name "SIMRAD" became known in the communications business, and was leading in echo sounding equipment.
In 1957 the company 'Simonsen & Mustad' followed in Horten.
In 1968 Simonsen backed out of these companies and started *'Simonsen Elektro (in Oslo) in 1970 and Simonsen Elektro Løkken' (in Løkken Verk). These companies produced automatic cell phones, in the NMT 450 system, and were leading in the Norwegian market until the 1980s.

Simonsen was decorated with the 'Defence Medal 1940–1945, the UK Defence Medal', the 'Haakon VII 70th Anniversary Medal' and the 'Order of St. Olav', and has received the 'Reginald Fessenden Award'. He died in December 2003.