The present invention relates to a radio device including a first mother unit for providing fundamental functions for the radio device, a first receiving unit for receiving signals and a first transmitting unit for transmitting signals. Each of the first mother unit, the first receiving unit and the first transmitting unit is a modularly designed unit such that it can be replaced with a corresponding second mother unit, second receiving unit or second transmitting unit. The radio device according to the present invention has the beneficial effect of facilitating scalability and being capable of reducing the maintenance costs.