text: Siemens launches new unit to focus on end-to-end systems  Synergy was the word Siemens AG used several years ago when it talked about combining its carrier and enterprise network and mobile phone businesses under one roof. Then the company spun off these operations into separate divisions to be able to focus -- it said -- more closely on customers' individual needs. Now the manufacturer is pulling everything back together and the buzzwords are end-to-end systems and convergence.