Essex Corp. announced it has received awards valued at $2 million that expand current signal processing engineering projects. Based in Columbia, Md., Essex designs optical components for the US military and other government agencies.   . . .   BAE SYSTEMS North America has named Robert T. Murphy as president of its technology solutions sector. He succeeds Bruce Hamilton, who has retired.   . . .   In a deal worth more than $945,000 (600,00 pounds), Carl Zeiss Inc. has supplied seven fluorescence microscopes with imaging systems for The Biomedical Research Centre at the University of East Anglia, in Norwich, England. The center will be a base for fifteen biomedical research groups, providing technology for research in diseases such as cancer, arthritis, diabetes, neurological disease, hearing disorders, cardiovascular disease and antibiotic resistance.