Allocation and logical to physical mapping of scheduling request indicator channel in wireless networks
A method for allocating resources for a scheduling request indicator (SRI) is disclosed. An SRI cycle period for use by user equipment (UE) within a cell is transmitted from a NodeB in a cell to UE within the cell. The NodeB transmits a specific SRI subframe offset and an index value to the particular UE within the cell. The specific SRI subframe offset and the index value enable the UE to determine a unique combination of cyclic shift, RS orthogonal cover, data orthogonal cover, and resource block number for the UE to use as a unique physical resource for an SRI in the physical uplink control channel (PUCCH).
1. A base station for use in a wireless network, comprising:
a processor operable to execute instructions, coupled to a memory containing instructions for the processor;
a radio receiver and a transmitter coupled to the processor;
wherein the transmitter is operable to:
transmit an SRI cycle period for use by user equipment (UE) within a cell;
transmit a specific SRI subframe offset to a first UE;
transmit an index value n to the first UE; and
wherein the specific SRI subframe offset and the index value n enable the first UE to determine a unique combination of cyclic shift, reference signal (RS) orthogonal cover, data orthogonal cover, and resource block number for the first UE to use as a unique physical resource for an SRI in the physical uplink control channel (PUCCH);
wherein the SRI is transmitted on a two-state SR channel.
2. The base station of claim 1 wherein the SRI cycle period extends the unique physical resource to a persistent periodic physical resource.
3. The base station of claim 1 wherein the SRI cycle period, the specific SRI subframe offset and the index value n are transmitted in UE-specific level three (L3) signaling in media access control (MAC) protocol data unit (PDU) on a physical downlink shared channel (PDSCH).
4. The base station of claim 1 , wherein the specific SRI subframe offset and the index value n enable the first UE to determine a unique combination, wherein an SRI resource indexed by n is located in a physical uplink control channel (PUCCH) resource block (RB) number wherein the PUCCH RB number is
[
n
mod
N
SRI
SFRB
N
SRI
N
SRI
SFRB
]
a subframe
S
0
+
⌊
n
mod
N
SRI
SFRB
N
SRI
N
SRI
SFRB
⌋
indicating where an SRI resource is located on a channelization resource indexed by n SRI (SRI resource index)=(n mod N SRI SFRB );
wherein the acronym SFRB means subframe source block;
wherein N SRI SFRB is the SRI multiplexing capacity in one subframe of an RB; and
wherein N SRI is the SRI period expressed in number subframes, and S0 is the number of a first subframe of an SRI period, and assuming a PUCCH RB indexing starts from an upper edge of the PUCCH down to a lower edge.
5. The base station of claim 4 , wherein N SRI SFRB is the SRI multiplexing capacity in one subframe of a RB, given a cyclic shift separation Δ shift PUCCH between resources using the same orthogonal covering code,
N
SRI
SFRB
=
{
6
N
SC
RB
/
Δ
shift
PUCCH
for
normal
cyclic
prefix
4
N
SC
RB
/
Δ
shift
PUCCH
for
extended
cyclic
prefix
,
wherein N SC RB is the number N of sub-carriers (SC) in one resource block (RB).
6. The base station of claim 4 , wherein resources used for SRI transmission on PUCCH in a given RB/subframe are identified by the resource index n SRI from which the orthogonal sequence indexes n OC,1 (n s ) , n OC,2 (n s ) , n OC,3 (n s ) of block spreading codes 1, 2 and 3 respectively, and a cyclic shift α(l) are determined according to:
n OC,1 (n s ) =( n OC,1 (0) +f 1 ( n s )) mod 3
n OC,2 (n s ) =( n OC,2 (0) +f 2 ( n s )) mod 3
n OC,3 (n s ) =( n OC,3 (0) +f 3 ( n s )) mod 3
α( l )=(α (0)+f 4 ( l )) mod N SC RB
where N SC RB =12 is the number of sub-carriers in one resource block (RB) and
n
OC
,
1
(
0
)
=
{
⌊
(
n
SRI
mod
(
N
SRI
SFRB
/
2
)
)
Δ
shift
PUCCH
/
N
SC
RB
⌋
for
normal
cyclic
prefix
2
⌊
(
n
SRI
mod
(
N
SRI
SFRB
/
2
)
)
Δ
shift
PUCCH
/
N
SC
RB
⌋
for
extended
cyclic
prefix
n
OC
,
2
(
0
)
=
⌊
(
n
SRI
mod
(
N
SRI
SFRB
/
2
)
)
Δ
shift
PUCCH
/
N
SC
RB
⌋
n
OC
,
3
(
0
)
=
⌊
2
n
SRI
/
N
SRI
SFRB
⌋
α
(
0
)
=
{
(
(
n
SRI
mod
(
N
SRI
SFRB
/
2
)
)
Δ
shift
PUCCH
+
δ
offset
PUCCH
+
(
n
OC
,
1
(
0
)
mod
Δ
shift
PUCCH
)
)
mod
N
SC
RB
normal
cp
(
(
n
SRI
mod
(
N
SRI
SFRB
/
2
)
)
Δ
shift
PUCCH
+
δ
offset
PUCCH
+
n
OC
,
2
(
0
)
)
mod
N
SC
RB
extended
cp
and f 1 (n s ), f 2 (n s ), f 3 (n s ) represent index hopping functions varying per slot and f 4 (l) represents index hopping function varying per symbol.
7. The base station of claim 1 , further comprising receiving an SRI from the first UE on the unique physical resource in accordance with the specific SRI subframe offset and the index value n.
8. A base station for use in a wireless network, comprising:
a processor operable to execute instructions, coupled to a memory containing instructions for the processor;
a radio receiver and a transmitter coupled to the processor;
wherein the receiver is operable to:
receive an SRI cycle period for use by user equipment (UE) within a cell;
receive a specific SRI subframe offset at a first UE;
receive an index value n at the first UE; and
determining a unique combination of cyclic shift, reference signal (RS) orthogonal cover, data orthogonal cover, and resource block number for the first UE to use as a unique physical resource for an SRI in the physical uplink control channel (PUCCH) according to the specific SRI subframe offset and the index value n;
wherein the SRI is transmitted on a two-state SR channel.
9. The base station of claim 8 wherein the SRI cycle period extends the unique physical resource to a persistent periodic physical resource.
10. The base station of claim 8 wherein the SRI cycle period, the specific SRI subframe offset and the index value n are received in level three (L3) signaling in media access control (MAC) protocol data unit (PDU) on a physical downlink shared channel (PDSCH).
11. The base station of claim 8 , wherein the specific SRI subframe offset and the index value n enable the first UE to determine a unique combination, wherein an SRI resource indexed by n is located in a physical uplink control channel (PUCCH) resource block (RB) number wherein the PUCCH RB number is
└n/N SRI SFRB N SRI ┘;
a subframe S 0 +└(n mod N SRI SFRB N SRI )/N SRI SFRB ┘ indicating where an SRI resource is located on a channelization resource indexed by n SRI (SRI resource index)=(n mod N SRI SFRB );
wherein the acronym SFRB means subframe source block;
wherein N SRI SFRB is the SRI multiplexing capacity in one subframe of a RB; and
wherein N SRI is the SRI period expressed in number subframes, and S0 is the number of a first subframe of an SRI period, and assuming a PUCCH RB indexing starts from an upper edge of the PUCCH down to a lower edge.
12. The base station of claim 11 , wherein N SRI SFRB is the SRI multiplexing capacity in one subframe of a RB, given a cyclic shift separation Δ shift PUCCH shift between resources using the same orthogonal covering code,
N
SRI
SFRB
=
{
6
N
SC
RB
/
Δ
shift
PUCCH
for
normal
cyclic
prefix
4
N
SC
RB
/
Δ
shift
PUCCH
for
extended
cyclic
prefix
,
wherein N SC RB is the number N of sub-carriers (SC) in one resource block (RB).
13. The base station of claim 11 , wherein resources used for SRI transmission on PUCCH in a given RB/subframe are identified by the resource index n SRI from which the orthogonal sequence indexes n OC,1 (n s ) , n OC,2 (n s ) , n OC,3 (n s ) of the block spreading codes 1, 2 and 3 respectively, and a cyclic shift α(l) are determined according to:
n OC,1 (n s ) =( n OC,1 (0) +f 1 ( n s )) mod 3
n OC,2 (n s ) =( n OC,2 (0) +f 2 ( n s )) mod 3
n OC,3 (n s ) =( n OC,3 (0) +f 3 ( n s )) mod 3
α( l )=)(α (0) ±f 4 ( l )) mod N SC RB
where N SC RB =12 is the number of sub-carriers in one resource block (RB) and
n
OC
,
1
(
0
)
=
{
⌊
(
n
SRI
mod
(
N
SRI
SFRB
/
2
)
)
Δ
shift
PUCCH
/
N
SC
RB
⌋
for
normal
cyclic
prefix
2
⌊
(
n
SRI
mod
(
N
SRI
SFRB
/
2
)
)
Δ
shift
PUCCH
/
N
SC
RB
⌋
for
extended
cyclic
prefix
n
OC
,
2
(
0
)
=
⌊
(
n
SRI
mod
(
N
SRI
SFRB
/
2
)
)
Δ
shift
PUCCH
/
N
SC
RB
⌋
n
OC
,
3
(
0
)
=
⌊
2
n
SRI
/
N
SRI
SFRB
⌋
α
(
0
)
=
{
(
(
n
SRI
mod
(
N
SRI
SFRB
/
2
)
)
Δ
shift
PUCCH
+
δ
offset
PUCCH
+
(
n
OC
,
1
(
0
)
mod
Δ
shift
PUCCH
)
)
mod
N
SC
RB
normal
cp
(
(
n
SRI
mod
(
N
SRI
SFRB
/
2
)
)
Δ
shift
PUCCH
+
δ
offset
PUCCH
+
n
OC
,
2
(
0
)
)
mod
N
SC
RB
extended
cp
and f 1 (n s ), f 2 (n s ), f 3 (n s ) represent index hopping functions varying per slot and f 4 (l) represents index hopping function varying per symbol.
14. The base station of claim 8 , further comprising transmitting an SRI from the first UE on the unique physical resource in accordance with the specific SRI subframe offset and the index value n.