General Brazilian
conexão sem fio
Most common usage; also used for WiFi and Bluetooth
Rio de Janeiro
conexão sem fio / conexão wireless
Often uses English term 'wireless' mixed with Portuguese
São Paulo
conexão sem fio
Standard usage; tech-savvy speakers may use 'wireless'
Portugal
ligação sem fios / conexão sem fios
Slightly different spelling with 'ligação' also commonly used