Roll-off parameter determining method and module

1. A roll-off parameter determining device, disposed at a receiving terminal, the receiving terminal comprising an analyzing module, the analyzing module analyzing a first frame and a second frame to identify first roll-off information in the first frame and second roll-off information in the second frame, the first frame being adjacent to the second frame, the roll-off parameter determining device comprising:

a register unit, storing the first roll-off information;

a first determining unit, determining whether one of the first roll-off information and the second roll-off information comprises a first data type according to the first roll-off information received from the register unit and the second roll-off information received from the analyzing module to generate a first roll-off parameter indicator;

a second determining unit, determining whether at least one of the first roll-off information and the second roll-off information comprises a second data type according to the first roll-off information received from the register unit and the second roll-off information received from the analyzing module to generate a second roll-off parameter indicator; and

a look-up table (LUT) unit, looking up an LUT according to the first roll-off parameter indicator and the second roll-off parameter indicator to output a roll-off parameter.

2. The roll-off parameter determining device according to claim 1 , wherein each of the first roll-off information and the second roll-off information is formed by two bits.

3. The roll-off parameter determining device according to claim 1 , wherein the first data type is “logic 11”.

4. The roll-off parameter determining device according to claim 1 , wherein the second data type is one of “logic 00”, “logic 01” and “logic 10”.

5. The roll-off parameter determining device according to claim 1 , wherein the register unit comprises:

a first register; and

a second register;

wherein, the first register stores a first bit of the first roll-off information, and the second register stores a second bit of the first roll-off information.

6. The roll-off parameter determining device according to claim 1 , wherein the first determining unit comprises:

a first OR gate, having a first input end coupled to the register unit and a second input end coupled to the analyzing module;

a second OR gate, having a first input end coupled to the register unit and a second input end coupled to the analyzing module; and

an AND gate, having a first AND input end, a second AND input end and an AND output end, the first AND input end coupled to a first OR output end of the first OR gate, the second AND input end coupled to a second OR output end of the second OR gate, and the AND gate outputting the first roll-off parameter indicator.

7. The roll-off parameter determining device according to claim 1 , wherein the second determining unit comprises:

a first AND gate, having a first input end coupled to the register unit and a second input end coupled to the analyzing module, outputting a first AND output bit; and

a second AND gate, having a first input end coupled to the register unit and a second input end coupled to the analyzing module, outputting a second AND output bit;

wherein, the second roll-off parameter indicator comprises the first AND output bit and the second AND output bit.

8. A roll-off parameter determining method, applied to a receiving terminal of a communication system, the receiving terminal comprising an analyzing module, the analyzing module analyzing a first frame and a second frame to identify first roll-off information in the first frame and second roll-off information in the second frame, the first frame being adjacent to the second frame, the roll-off parameter determining method comprising:

storing the first roll-off information in a register unit;

determining, with a first determining unit, whether one of the first roll-off information and the second roll-off information comprises a first data type according to the first roll-off information received from the register unit and the second roll-off information received from the analyzing module to generate a first roll-off parameter indicator;

determining, with a second determining unit, whether at least one of the first roll-off information and the second roll-off information comprises a second data type according to the first roll-off information received from the register unit and the second roll-off information received from the analyzing module to generate a second roll-off parameter indicator; and

looking up a look-up table (LUT) according to the first roll-off parameter indicator and the second roll-off parameter indicator to output a roll-off parameter.

9. The roll-off parameter determining method according to claim 8 , wherein each of the first roll-off information and the second roll-off information is formed by two bits.

10. The roll-off parameter determining method according to claim 8 , wherein the first data type is “logic 11”.

11. The roll-off parameter determining method according to claim 8 , wherein the second data type is one of “logic 00”, “logic 01” and “logic 10”.

12. A receiving terminal, comprising:

an analyzing module, analyzing a first frame and a second frame to identify first roll-off information in the first frame and second roll-off information in the second frame, the first frame being adjacent to the second frame; and

a roll-off parameter determining module, outputting a roll-off parameter according to the first roll-off information and the second roll-off information.

13. The receiving terminal according to claim 12 , wherein the roll-off parameter determining module comprises:

a register unit, storing the first roll-off information;

a roll-off parameter determining unit, outputting the roll-off parameter according to the first roll-off information received from the register unit and the second roll-off information received from the analyzing module.

14. The receiving terminal according to claim 13 , wherein the roll-off parameter determining unit comprises:

a first determining unit, determining whether one of the first roll-off information and the second roll-off information comprises a first data type to generate a first roll-off parameter indicator; and

a second determining unit, determining whether at least one of the first roll-off information and the second roll-off information comprises a second data type to generate a second roll-off parameter indicator;

wherein the roll-off parameter determining unit outputs the roll-off parameter according to the first roll-off parameter indicator and the second roll-off parameter indicator.

15. The receiving terminal according to claim 14 , wherein the roll-off parameter determining unit further comprises:

a look-up table (LUT) unit, looking up an LUT according to the first roll-off parameter indicator and the second roll-off parameter indicator to output the roll-off parameter.