Qualcomm Inc. said it sued Ericsson of Sweden on charges of unfair competition in a suit that comes on the heels of an Ericsson suit claiming the San Diego company infringed eight of Ericsson's wireless telephone patents. Qualcomm said in its suit filed in U.S. District Court in San Diego that Ericsson's patent infringement charges violate a nondisclosure pact between the companies. It also seeks a declaration that its patents don't infringe Ericsson's patents and charges Ericsson has disparaged Qualcomm products. The suit is the latest conflict between the two companies, which back rival technologies in the fast-growing market for digital wireless equipment. Qualcomm focuses on a wireless technology known as code-division multiple-access, or CDMA. Ericsson also deals in CDMA, though it has largely backed a rival technology called time-division multiple-access, or TDMA, and a similar technology known as GSM. An Ericsson spokeswoman said the Qualcomm charges were "without merit."