A wireless communication system that communicates (500) frames having first and second sub-frames (510, 520) with time-frequency resource elements. The first sub-frame including first reference symbol information and the second sub-frame including second reference symbol information, and not more than one of the first and second sub-frames including user specific radio resource assignment information. Wireless communication entities receiving the frames process the time-frequency elements of the first sub-frame using the first reference symbol information and processing the time-frequency elements of the second sub-frame using the second reference symbol information.