Patent ID: 7174139

Claim:
A device for controlling a relative delay between a same analog R.F. output signal of a plurality of digital radio transmission branches in a digital radio transmitter system, each radio transmission branch including a digital part for receiving a digital input signal, a digital to analog converter for converting the digital input signal to an analog signal, and an analog part converting the analog signal to an analog RF output signal, comprising: at least one interface for receiving absolute delay information signals for each radio transmission branch; a processing unit for (1) determining an absolute delay for each radio transmission branch by determining a time difference between feeding an input signal into the radio transmission branch and providing a corresponding RF output signal from the radio transmission branch, and (2) determining the relative delay between outputing the same R.F. output signal from each radio transmission branch based on the received absolute delay information signals; and adjusting circuitry for adjusting in the digital part of one of the radio transmission branches the absolute delay of that one radio transmission branch in accordance with the determined relative delay.