RESOURCE ALLOCATION IN COMMUNICATIONS SYSTEM

• US 20140092790A1
• Filed: 09/30/2013
• Published: 04/03/2014
• Est. Priority Date: 09/28/2012
• Status: Active Grant

• Current Assignee: Nokia Technologies Oy (Nokia Corporation)
• Original Assignee: Nokia Solutions and Networks US LLC (Nokia Corporation)
• Inventors: ZHANG, Li, Lunttila, Timo Erkki, Tiirola, Esa Tapani
• Granted Patent: US 9,729,295 B2
• Time in Patent Office: Days
• US Class Current: 370/280
• CPC Class Codes: H04L 1/1861 Physical mapping arrangements for ACK signaling see also H04L5/0053
• CPC Class Codes: H04L 5/001 the frequencies being arranged in component carriers
• CPC Class Codes: H04L 5/0053 Allocation of signaling, i.e. of overhead other than pilot signals
• CPC Class Codes: H04L 5/0055 Physical resource allocation for ACK/NACK for physical mapping arrangements in ARQ protocols H04L1/1861
• CPC Class Codes: H04L 5/1469 using time-sharing

Abstract

An exemplary embodiment discloses a multi-subframe physical uplink control channel PUCCH resource arrangement for PUCCH format 1a/1b resource allocation for enhanced physical downlink control channel EPDCCH in time division duplex TDD transmission. A definition of a semi-static offset for each EPDCCH set is extended by considering multiple downlink subframes, and a dynamic offset mechanism is enhanced to avoid resource collision between multiple DL subframes.

Claims

1. A method for resource allocation in a communications system, characterized by

determining, in a network apparatus, PUCCH format 1a/1b resources for HARQ-ACK for time division duplex signaling based on

an index of the first enhanced control channel element used for transmission of a corresponding EPDCCH downlink assignment in an uplink subframe,

the index of the downlink subframe in which the EPDCCH downlink assignment is transmitted, and

one or more configured parameters.

2. A method as claimed in claim 1, characterized by the one or more configured parameters comprising one or more of:

a first semi-static user terminal-specific resource starting offset defined for an EPDCCH set,

a second user terminal-specific resource offset defined for each EPDCCH set,

a dynamic offset modifier.

3. A method as claimed in claim 1, characterized in that a multi-subframe PUCCH format 1a/1b resource allocation is carried out for HARQ-ACK corresponding to PDSCH scheduled via EPDCCH.

4. A method as claimed in claim 1, characterized in that when M=1, the resource determination is independent of the second user terminal-specific resource offset.

5. A method as claimed in claim 1, characterized in that for time division duplex signaling when M>

1, the second user terminal-specific resource offset impacts resource allocation when PUCCH HARQ-ACK resources for multiple downlink subframes map into a single uplink subframe.

6. A method as claimed in claim 1, characterized in that the offset for each EPDCCH set applied in each downlink subframe is dependent on the first semi-static user terminal-specific resource starting offset, second user terminal-specific resource offset, and m, where m(0 . . . M−

1) is a relative index of the downlink subframe, M being the number of downlink subframes associated with an uplink subframe for HARQ-ACK feedback.

7. A method as claimed in claim 1, characterized in that the dynamic offset modifier k is dependent on an antenna port or a power control command.

8. A method as claimed in claim 1, characterized in that the dynamic offset modifier is applied such that it is independent on a subframe index m, wherein the dynamic offset modifier is derived based on downlink control information DCI that EPDCCH is carrying.

9. A method as claimed in claim 1, characterized in that a dynamic offset modifier is applied such that the dynamic offset modifier depends on a subframe index m, wherein multiple sets of dynamic offset modifiers are defined to be a matrix C with (M−

1) columns and N rows, N corresponding to the number of options to perform dynamic switching, M being the number of downlink subframes associated with an uplink subframe for HARQ-ACK feedback, and the subframe index m is used as one factor to determine the value of the dynamic offset modifier k(n, m), where n is an index of dynamic switching option signaled as downlink control information DCI via EPDCCH.

10. A method as claimed in claim 9, characterized in that the resource index of the ACK/NACK resource corresponding to the m-th subframe X_m is derived from the resource index of the first subframe X₀ as X₀+C(m), where C(m) is a predefined constant number.

11. A method as claimed in claim 10, characterized in that the matrix C is configured via a protocol layer higher than the physical layer.

12. A method as claimed in claim 1, characterized in that the dynamic offset modifier k is an antenna port-specific offset associated with antenna port p, where p is the antenna port allocated to the first control channel element CCE of corresponding EPDCCH or other explicitly signaled or implicitly derived parameter.

13. A method as claimed in claim 1, characterized by scheduling the PUCCH format 1a/1b resources for EPDCCH for time division duplex signaling based on formula I:

n_PUCCH⁽¹⁾=N_UE-PUCCH-TDD⁽¹⁾*m+n_eCCE+N_UE-PUCCH⁽¹⁾+k,  

 

(III)

where

n_PUCCH⁽¹⁾ is a PUCCH format 1a/1b resource to be allocated for a HARQ-ACK signal;

N_UE-PUCCH⁽¹⁾ is the first semi-static user terminal-specific resource starting offset defined for an EPDCCH set;

N_UE-PUCCH-TDD⁽¹⁾ is the second user terminal-specific resource offset defined for EPDCCH sets when M>

1, M being the number of downlink subframes associated with an uplink subframe for HARQ-ACK feedback, m being a relative index of a downlink subframe, wherein 0≦

m≦

M−

1;

n_eCCE is an index of the first enhanced control channel element eCCE used for transmission of a corresponding EPDCCH downlink assignment in a downlink subframe n−

k_m, where m is the relative index of the downlink subframes and 0≦

m≦

M−

1;

k is a dynamic offset modifier.

30. A computer program product, characterized by comprising program code means configured to perform any of method steps of claim 1 when the program is run on a computer.

31. A computer-readable storage medium, characterized by comprising program code means configured to perform the method steps of claim 1 when executed on a computer.

14. An apparatus comprising at least one processor;

and at least one memory including a computer program code, characterized in that the at least one memory and the computer program code are configured to, with the at least one processor, cause the apparatus to

determine PUCCH format 1a/1b resources for HARQ-ACK for time division duplex signaling based on

an index of the first enhanced control channel element used for transmission of a corresponding EPDCCH downlink assignment in an uplink subframe,

the index of the downlink subframe in which the EPDCCH downlink assignment is transmitted, and

one or more configured parameters.

15. An apparatus as claimed in claim 14, characterized in that the one or more configured parameters comprise one or more of:

a first semi-static user terminal-specific resource starting offset defined for an EPDCCH set,

a second user terminal-specific resource offset defined for each EPDCCH set,

a dynamic offset modifier.

16. An apparatus as claimed in claim 14, characterized in that the at least one memory and the computer program code are configured to, with the at least one processor, cause the apparatus to carry out a multi-subframe PUCCH format 1a/1b resource allocation for HARQ-ACK corresponding to PDSCH scheduled via EPDCCH.

17. An apparatus as claimed in claim 14, characterized in that when M=1, the resource determination is independent of the second user terminal-specific resource offset.

18. An apparatus as claimed in claim 14, characterized in that for time division duplex signaling when M>

1, the second user terminal-specific resource offset impacts resource allocation when PUCCH HARQ-ACK resources for multiple downlink subframes map into a single uplink subframe.

19. An apparatus as claimed in claim 14, characterized in that the offset for each EPDCCH set applied in each downlink subframe is dependent on the first semi-static user terminal-specific resource starting offset, second user terminal-specific resource offset, and m, where m(0 . . . M−

1) is a relative index of the downlink subframe, M being the number of downlink subframes associated with an uplink subframe for HARQ-ACK feedback.

20. An apparatus as claimed in claim 14, characterized in that the at least one memory and the computer program code are configured to, with the at least one processor, cause the apparatus to apply the dynamic offset modifier k dependent on an antenna port or a power control command.

21. An apparatus as claimed in claim 14, characterized in that the at least one memory and the computer program code are configured to, with the at least one processor, cause the apparatus to apply the dynamic offset modifier such that it is independent on a subframe index m, wherein the dynamic offset modifier is derived based on downlink control information DCI that EPDCCH is carrying.

22. An apparatus as claimed in claim 14, characterized in that the at least one memory and the computer program code are configured to, with the at least one processor, cause the apparatus to apply the dynamic offset modifier such that the dynamic offset modifier depends on a subframe index m, wherein multiple sets of dynamic offset modifiers are defined to be a matrix C with (M−

1) columns and N rows, N corresponding to the number of options to perform dynamic switching, M being the number of downlink subframes associated with an uplink subframe for HARQ-ACK feedback, and the subframe index m is used as one factor to determine the value of the dynamic offset modifier k(n, m), where n is an index of dynamic switching option.

23. An apparatus as claimed in claim 22, characterized in that the resource index of the ACK/NACK resource corresponding to the m-th subframe X_m is derived from the resource index of the first subframe X₀ as X₀+C(m), where C(m) is a predefined constant number.

24. An apparatus as claimed in claim 23, characterized in that the at least one memory and the computer program code are configured to, with the at least one processor, cause the apparatus to define the matrix C via a protocol layer higher than the physical layer.

25. An apparatus as claimed in claim 14, characterized in that the dynamic offset modifier k is an antenna port-specific offset associated with antenna port p, where p is the antenna port allocated to the first control channel element CCE of corresponding EPDCCH or other explicitly signaled or implicitly derived parameter.

26. An apparatus as claimed in claim 14, characterized in that the at least one memory and the computer program code are configured to, with the at least one processor, cause the apparatus to set the parameter N_UE-PUCCH-TDD⁽¹⁾ as

the number of PUCCH resources corresponding to a first EPDCCH set+the number of PUCCH resources corresponding to a second EPDCCH set;

or

the number of eCCEs in the first EPDCCH set+the number of eCCEs in the second EPDCCH set.

27. An apparatus as claimed in claim 14, characterized in that the at least one memory and the computer program code are configured to, with the at least one processor, cause the apparatus to schedule the PUCCH format 1a/1b resources for EPDCCH for time division duplex signaling based on formula I:

n_PUCCH⁽¹⁾=N_UE-PUCCH-TDD⁽¹⁾*m+n_eCCE+N_UE-PUCCH⁽¹⁾+k,  

 

(IV)

where

n_PUCCH⁽¹⁾ is a PUCCH format 1a/1b resource to be allocated for a HARQ-ACK signal;

N_UE-PUCCH⁽¹⁾ is the first semi-static user terminal-specific resource starting offset defined for an EPDCCH set;

N_UE-PUCCH-TDD⁽¹⁾ is the second user terminal-specific resource offset defined for EPDCCH sets when M>

1, M being the number of downlink subframes associated with an uplink subframe for HARQ-ACK feedback, m being a relative index of a downlink subframe, wherein 0≦

m≦

M−

1;

n_eCCE is an index of the first enhanced control channel element eCCE used for transmission of a corresponding EPDCCH downlink assignment in a downlink subframe n−

k_m,

where m is the relative index of the downlink subframes and 0≦

m≦

M−

1;

k is a dynamic offset modifier.

28. A user terminal comprising at least one processor;

and at least one memory including a computer program code, characterized in that the at least one memory and the computer program code are configured to, with the at least one processor, cause the user terminal to

apply PUCCH format 1a/1b resource mapping for EPDCCH scheduled PDSCH for time division duplex signaling based on

an index of the first enhanced control channel element used for transmission of a corresponding EPDCCH downlink assignment in an uplink subframe,

the index of the downlink subframe in which the EPDCCH downlink assignment is transmitted, and

one or more configured parameters.

29. A user terminal as claimed in claim 28, characterized by the one or more configured parameters comprising one or more of:

a first semi-static user terminal-specific resource starting offset defined for an EPDCCH set,

a second user terminal-specific resource offset defined for each EPDCCH set,

a dynamic offset modifier.