A transmission method for use in a multi-hop wireless communication system is provided. The system uses a time-frequency format in assigning available transmission frequency bandwidth during a discrete transmission interval. The format defines transmission windows within an interval, each window occupying a part of that interval and having a frequency bandwidth profile, each said window being assignable for a transmission interval. The transmission windows include an initial control window for control information transmission and a relay window for transmission by a source apparatus to an intermediate apparatus. The relay window is defined as the last window in the discrete transmission interval assignable to the source apparatus for transmission. The method includes employing the format to assign the control window to a source apparatus and to an intermediate apparatus for control information transmission and to assign the relay window to the source apparatus for data transmission to the intermediate apparatus.