A method for transmitting information in a wireless system is provided. In this method, the traffic on a plurality of channels can be determined. A bandwidth for a packet can be selected based on the traffic and available channel bandwidths. A modulation and a coding rate can be selected from a plurality of modulations and associated coding rates. The modulation and coding rate can be applied to a segment of the packet, wherein each segment includes one or more bandwidth units. The packet including the selected modulation and coding rate therein can be transmitted on at least one channel