Method of radio coverage extension and base station using the same

1. A radio coverage extension method applicable to a base station, the method comprising:

transmitting a system information in a radio frame through a broadcast channel, wherein the system information is transmitted through a master information block (MIB);

selecting a payload structure of repetitive system information from a plurality of predefined payload structures comprising a first payload structure and a second payload structure, wherein

the first payload structure has a first payload size, the second payload structure has a second payload size, and the first payload size is greater than the second payload size; and

transmitting within the same radio frame a plurality of the repetitive system information having the payload structure through the broadcast channel in response to transmitting the system information, wherein

when the first payload structure has been selected, there are N1 number of the repetitive system information, when the second payload structure has been selected, there are N2 number of repetitive system information, and N2 is smaller than or equal to N1, wherein N1 and N2 are both integers greater than 0.

2. The method of claim 1 , wherein the first payload structure has the same content as the system information.

3. The method of claim 1 , wherein the first payload structure has reduced content relative to the system information.

4. The method of claim 1 , wherein selecting the payload structure of repetitive system information from the plurality of predefined payload structures comprising:

selecting the payload structure of repetitive system information from a third payload structure having a third payload size which is smaller than the second payload size; and

transmitting within the same radio frame N3 number of the repetitive system information having the payload structure having the third payload size for N3, wherein N3 is smaller than or equal to N2, wherein N3 is the integer greater than 0.

5. The method of 1 , wherein selecting the payload structure of repetitive system information from the plurality of predefined payload structures comprising:

selecting the payload structure of repetitive system information from the plurality of predefined payload structures based on instantaneous data traffic so that the first payload size is preferred over the second payload size when the instantaneous data traffic has increased.

6. The method of 1 , wherein selecting the payload structure of repetitive system information from the plurality of predefined payload structures comprising:

selecting the payload structure of repetitive system information from the plurality of predefined payload structures based on system requirement so that the first payload size is preferred over the second payload size when the system information has increased.

7. The method of 1 , wherein selecting the payload structure of repetitive system information from the plurality of predefined payload structures comprising:

selecting the payload structure of repetitive system information from the plurality of predefined payload structures based on cell type so that the first payload size is preferred over the second payload size when the base station is a Macro cell.

8. The method of claim 1 , wherein the plurality of predefined payload structures comprises reduced system information content.

9. The method of claim 1 , wherein the plurality of predefined payload structures comprises reduced spare bits.

10. The method of claim 1 , wherein the plurality of predefined payload structures comprises reduced error detecting code.

11. A base station comprising:

a transmitter, configured to transmit wireless data; and

a processing circuit, coupled to the transmitter and configured to:

transmit a system information in a radio frame through a broadcast channel by using the transmitter, wherein the system information is transmitted through a master information block (MIB);

select a payload structure of repetitive system information from a plurality of predefined payload structures comprising a first payload structure and a second payload structure, wherein

the first payload structure has a first payload size, the second payload structure has a second payload size, and the first payload size is greater than the second payload size; and

transmit within the same radio frame a plurality of the repetitive system information having the payload structure through the broadcast channel in response to transmitting the system information by using the transmitter, wherein

when the first payload structure has been selected, there are N1 number of the repetitive system information, when the second payload structure has been selected, there are N2 number of repetitive system information, and N2 is smaller than or equal to N1, wherein N1 and N2 are both integers greater than 0.

12. The base station of claim 11 , wherein the first payload structure has the same content as the system information.

13. The base station of claim 11 , wherein the first payload structure has reduced content relative to the system information.

14. The base station of claim 11 , wherein the processing circuit is configured for selecting the payload structure of repetitive system information from the plurality of predefined payload structures comprising:

selecting the payload structure of repetitive system information from a third payload structure having a third payload size which is smaller than the second payload size; and

transmitting within the same radio frame N3 number of the repetitive system information having the payload structure having the third payload size for N3, wherein N3 is smaller than or equal to N2, wherein N3 is the integer greater than 0.

15. The base station of 11 , wherein the processing circuit is configured for selecting the payload structure of repetitive system information from the plurality of predefined payload structures comprising:

selecting the payload structure of repetitive system information from the plurality of predefined payload structures based on instantaneous data traffic so that the first payload size is preferred over the second payload size when the instantaneous data traffic has increased.

16. The base station of 11 , wherein the processing circuit is configured for selecting the payload structure of repetitive system information from the plurality of predefined payload structures comprising:

selecting the payload structure of repetitive system information from the plurality of predefined payload structures based on system requirement so that the first payload size is preferred over the second payload size when the system information has increased.

17. The base station of 11 , wherein the processing circuit is configured for selecting the payload structure of repetitive system information from the plurality of predefined payload structures comprising:

selecting the payload structure of repetitive system information from the plurality of predefined payload structures based on cell type so that the first payload size is preferred over the second payload size when the base station is a Macro cell.

18. The base station of claim 11 , wherein the plurality of predefined payload structures comprises reduced system information content.

19. The base station of claim 11 , wherein the plurality of predefined payload structures comprises reduced spare bits.

20. The base station of claim 11 , wherein the plurality of predefined payload structures comprises reduced error detecting code.