Method of handling downlink control information and related communication device

1. A method of arranging downlink (DL) control information (DCI) for a network of a wireless communication system, the method comprising:

configuring first DCI and at least one second DCI for a communication device of the wireless communication system;

transmitting the first DCI in a physical DL control channel (PDCCH) of a first transmission time interval (TTI) of a first component carrier, for indicating a control region of a first physical DL shared channel (PDSCH) to the communication device; and

transmitting the at least one second DCI in the control region of the first physical DL shared channel (PDSCH) of the first TTI of the first component carrier to the communication device, wherein the first DCI transmitted in the PDCCH of the first TTI of the first component carrier is different from the at least one second DCI in the control region of the first PDSCH of the first TTI of the first component carrier.

2. The method of claim 1 , wherein the at least one second DCI comprises an arrangement of a second PDSCH of a second TTI of a second component carrier to the communication device.

3. The method of claim 2 , wherein hybrid automatic repeat request (HARQ) resource for transmitting a HARQ corresponding to the second PDSCH is determined according to at least one of a location of the at least one second DCI and a location of the second PDSCH.

4. The method of claim 1 , wherein the at least one second DCI comprises an arrangement of a physical uplink (UL) shared channel (PUSCH) of a second TTI of a second component carrier to the communication device.

5. The method of claim 1 , wherein the at least one second DCI comprises an indication for power control of the communication device.

6. The method of claim 1 , wherein the at least one second DCI comprises a HARQ corresponding to a PUSCH transmitted in a previous frame.

7. The method of claim 1 , further comprising:

transmitting a header in the first PDSCH of the first TTI of the first component carrier, for indicating the control region to the communication device.

8. The method of claim 7 , wherein the header comprises information related to at least one of a size and a location of the control region.

9. The method of claim 7 , wherein a modulation and coding scheme (MCS) of the header and the control region is different from a MCS of data transmitted in the first PDSCH.

10. The method of claim 1 , wherein the first DCI comprises at least one legacy field and at least one field newly added, wherein the at least one field newly added comprises information related to at least one of a size and a location of the control region.

11. The method of claim 1 , wherein a size of the control region for carrying the at least one second DCI is determined according to at least one of a modulation order and a size of the first PDSCH.

12. A method of detecting downlink (DL) control information (DCI) for a communication device of a wireless communication system, the method comprising:

receiving, by the communication device, first DCI in a physical DL control channel (PDCCH) of a first transmission time interval (TTI) of a first component carrier, wherein the first DCI indicates a control region of a first physical DL shared channel (PDSCH); and

receiving, by the communication device, the control region of the first physical DL shared channel (PDSCH) of the first TTI of the first component carrier; and

detecting, by the communication device, at least one second DCI in the control region of the first PDSCH, wherein the first DCI transmitted in the PDCCH of the first TTI of the first component carrier is different from the at least one second DCI in the control region of the first PDSCH of the first TTI of the first component carrier.

13. The method of claim 12 , wherein the at least one second DCI comprises an arrangement of a second PDSCH of a second TTI of a second component carrier to the communication device.

14. The method of claim 13 , wherein hybrid automatic repeat request (HARQ) resource for transmitting a HARQ corresponding to the second PDSCH is determined according to at least one of a location of the at least one second DCI and a location of the second PDSCH.

15. The method of claim 12 , wherein the at least one second DCI comprises an arrangement of a physical uplink (UL) shared channel (PUSCH) of a second TTI of a second component carrier to the communication device.

16. The method of claim 12 , wherein the at least one second DCI comprises an indication for power control of the communication device.

17. The method of claim 12 , wherein the at least one second DCI comprises a HARQ corresponding to a PUSCH transmitted in a previous frame.

18. The method of claim 12 , further comprising:

receiving a header transmitted by a network of the wireless communication system in the first PDSCH of the first TTI of the first component carrier, wherein the header indicates the control region.

19. The method of claim 18 , wherein the header comprises information related to at least one of a size and a location of the control region.

20. The method of claim 18 , wherein a modulation and coding scheme (MCS) of the header and the control region is different from a MCS of data transmitted in the first PDSCH.

21. The method of claim 12 , wherein the first DCI comprises at least one legacy field and at least one field newly added, wherein the at least one field newly added comprises information related to at least one of a size and a location of the control region.

22. The method of claim 12 , wherein a size of the control region for carrying the at least one second DCI is determined according to at least one of a modulation order and a size of the first PDSCH.

23. The method of claim 2 , wherein the first TTI and the second TTI are the same TTI or different TTIs.

24. The method of claim 2 , wherein the first component carrier and the second component carrier are the same component carrier or different component carriers.

25. The method of claim 13 , wherein the first TTI and the second TTI are the same TTI or different TTIs.

26. The method of claim 13 , wherein the first component carrier and the second component carrier are the same component carrier or different component carriers.