Disclosed is a system and method for multiple wireless communication devices (WCDs) to share a resource block in an orthogonal frequency division multiplexing communication system by assigning each WCD a different one of multiple different sub-segments of the resource block. A base station can allocate the shared resource block on to the WCDs, and use hash function applied to each WCD to assign a different one of the sub-segments to each WCD. Each of the WCDs can apply the same hash function to determine the same sub-segment assignment made by the base station. For downlink communications, the base station can transmit data to each WCD in the assigned sub-segment, and each WCD can recover its data from its assigned sub-segment. For uplink communications, each WCD can transmit its data to the base station in its assigned sub-segment, and the base station can recover each WCD's data from the assigned sub-segment.