WE CLAIM:
1. A communications method comprising:
creating a group of a plurality of mobile terminals (3), the mobile terminals carrying out a detection of a candidate set including control channel elements which are used for transmission of an L1/L2 control signal from a base station (2), the base station carrying out communications using a plurality of frequency bands, each of which is one of a plurality of regions into which one of said plurality of frequency bands is divided, where one of the plurality of mobile terminals is a destination of transmission of said L1/L2 control signal on a basis of attribution information of said one of the plurality of mobile terminals; and
performing a detection process on said candidate set corresponding to the group of the plurality of mobile terminals, and reading said L1/L2 control signal from the control channel elements included in said candidate set;
adding a load on the group of the plurality of mobile terminals in response to a variation occurring in a number of acknowledgments/non-acknowledgements received by the group of the plurality of mobile terminals; and
wherein said control channel elements are of a non-uniform size.
2. The method as claimed in claim 1, wherein the base station further transmits a control channel element group which includes acknowledgement/non-acknowledgement information.
3. The method as claimed in claim 1, wherein the base station further transmits a control channel element group which includes a combination of acknowledgement/non-acknowledgement information and other L1/L2 control information, wherein the acknowledgement/non-acknowledgement information may be omitted if at least one of the plurality of mobile terminals are not expecting acknowledgement/non-acknowledgement information.
4. The method as claimed in claim 1, wherein the step of performing a detection process is done at a fixed time.
5. The method as claimed in claim 1, wherein the step of performing a detection process is done when a predetermined event occurs.
6. The method as claimed in claim 1, further comprising transmitting a signal including a control channel element group including acknowledgement/non-acknowledgement information.

7. The method as claimed in claim 6, wherein the signal including a control channel element group including acknowledgement/non-acknowledgement information further comprises a control channel element group including other L1/L2 control information.
8. The method as claimed in claim 7, wherein the signal including a control channel element group including acknowledgement/non-acknowledgement information and a control channel element group including other L1/L2 control information further comprises a common control channel element group.
9. A communication system, comprising:
a base station (2) which groups a plurality of mobile terminals (3) and assigns the plurality of mobile terminals to a plurality of frequency bands and transmits a L1/L2 control signal including a control channel elements group with uplink control information and a control channel elements group with downlink control information to at least one of the plurality of mobile terminals; and
at least one mobile terminal (3) which receives the at least one L1/L2 control signal selected from a candidate set and performs a detection and a demodulation process based on the type of control channel element group, wherein the candidate set is created from values of the L1/L2 control signal at a time when a system bandwidth varies; and
wherein a mobile terminal (3) which has not sent a request for an uplink channel performs no demodulation process on an uplink control channel element group.
10. The system as claimed in claim 9, wherein the uplink control channel element group comprises acknowledgement/non-acknowledgement information.
11. The system as claimed in claim 10, wherein the uplink control channel element group further comprises other L1/L2 control channel information.
12. The system as claimed in claim 9, wherein the base station groups the plurality of mobile terminals into a plurality of groups based on the signal quality indicator transmitted by each of the plurality of mobile terminals.
13. The system as claimed in claim 9, wherein cutoff values for each group of the plurality of mobile terminals is predetermined.
14. The system as claimed in claim 13, wherein the plurality of mobile terminals are grouped into a high quality signal group, a medium quality signal group, and a low quality signal group.

15. A communications system, comprising:
a base station (2) configured to group a plurality of mobile terminals (3) and assigns the plurality of mobile terminals to a plurality of frequency bands and transmit an L1/L2 control signal, and receive a signal quality indicator from the plurality of mobile terminals; and
a mobile terminal (3) which receives the L1/L2 control signal selected from a candidate set for a selected bandwidth transmitted from a base station (2), and transmits the signal quality indicator to the base station, wherein the candidate set is determined by referring to a bandwidth table, wherein the candidate set is assigned to the selected bandwidth in the bandwidth table;
wherein the base station groups the plurality of mobile terminals into a plurality of groups based on the signal quality indicator transmitted by each of the plurality of mobile terminals.
16. The system as claimed in claim 15, wherein cutoff values for each group of the plurality of mobile terminals is predetermined.
17. The system as claimed in claim 15, wherein the plurality of mobile terminals are grouped into a high quality signal group, a medium quality signal group, and a low quality signal group.
18. The system as claimed in claim 15, wherein the L1/L2 control signal comprises a plurality of control channel element groups.
19. The system as claimed in claim 18, wherein one of the plurality of control channel element groups comprises acknowledgement/non-acknowledgement information.
20. The system as claimed in claim 18, wherein one of the plurality of control channel element groups comprises acknowledgement/non-acknowledgement information and other L1/L2 control information.