The 4th-generation (4G) communication system, which is a future communication system, is advancing to providing users with services of various Quality of Service (QoS) levels at a transfer rate of about 100 Mbps. Its representative examples include an Institute of Electrical and Electronics Engineers (IEEE) 802.16 communication system. The IEEE 802.16 communication system adopts Orthogonal Frequency Division Multiplexing (OFDM)/Orthogonal Frequency Division Multiple Access (OFDMA) scheme to support a broadband transmission network in physical channels.
To support terminals of different available bandwidths at the same time, the broadband wireless communication system can adopt a frequency overlay scheme. The frequency overlay scheme supports the terminals that use different bandwidths, using a plurality of Frequency Assignments (FAs). For example, a base station 101 divides the whole band into two 10-MHz FAs 110 and 120 and supports one or two FAs according to a supportable bandwidth of the terminal as illustrated in FIG. 1. A terminal A 103 can use two FAs and a terminal B 105 can use only one FA. Accordingly, the base station 101 communicates with the terminal A 103 through the first FA 110 and the second FA 120, and communicates with the terminal B 105 through the second FA 120.
Typically, when the multiple FAs are used, each FA confirms to the independent frame structure. Thus, the resource allocation in each FA is independently carried out and a MAP message for informing of the resource allocation result is provided per FA. Yet, when one terminal makes use of the multiple FAs at the same time as in the frequency overlay scheme, the terminal needs to check the multiple MAP messages received in the FAs. That is, the resource allocation information for one terminal is delivered through the multiple MAP messages. As a result, the resource allocation information for the terminal using the multiple FAs increases in proportion to the number of the FAs in use and thus the MAP messages increases overhead.