Variable coherence adaptive antenna array
A user equipment (UE) ( 200, 500, 1530 ) transmits data to a base station ( 100, 500, 1520 ) in a wireless communication network. The UE ( 200, 500, 1530 ) comprises multiple antenna ports, and selects a precoding matrix from a respective first, second, third, or fourth set of precoding matrices according to a number of spatial layers. The first, second, third, and fourth sets of precoding matrices are available for all coherence capabilities and are comprised within a larger set of precoding matrices. The larger set comprises precoding matrices that are not available for all coherence capabilities. The first, second, third, and fourth sets of precoding matrices correspond to one, two, three, or four spatial layers, respectively. The number of columns in the selected precoding matrix is equal to the number of spatial layers and each column comprises a single non-zero element and one or more zero elements. The UE ( 200, 500, 1530 ) transmits data on the number of spatial layers according to the selected precoding matrix.
1. A method implemented by a user equipment (UE) of receiving precoding matrix indication from a base station in a wireless communication network, the UE being configured to transmit over multiple antenna ports, said method comprising:
receiving a control message from a base station including a precoding matrix indication field configurable to at least a first and second configuration,
wherein:
the first configuration of the precoding matrix indication field identifies precoding matrices in both a first set and a second set of precoding matrices, where the first and second set of precoding matrices correspond to a requirement for a first and second transmission coherence of the UE, respectively;
the second configuration of the precoding matrix indication field identifies precoding matrices in the second set of precoding matrices, but not the first set of precoding matrices;
the precoding matrix indication field is further configurable to a third configuration;
the third configuration of the precoding matrix indication field identifies precoding matrices in a third set of precoding matrices, in addition to the first and second sets of precoding matrices, the third set of precoding matrices corresponding to a requirement for a third transmission coherence of the UE; and
for maximum of four spatial layers, the first, second and third configurations of the precoding matrix indication field occupy 5 , 4 and 6 information bits, respectively.
2. The method of claim 1 , wherein the first, second and third transmission coherence represent partial coherence, non-coherence and full coherence, respectively.
3. The method of claim 1 , wherein the first transmission coherence represents partial coherence and the first set of precoding matrices includes
1
2
[
1
0
0
1
1
0
0
-
j
]
,
1
2
[
1
0
0
1
1
0
0
j
]
,
1
2
[
1
0
0
1
-
j
0
0
1
]
,
1
2
[
1
0
0
1
-
j
0
0
-
1
]
,
1
2
[
1
0
0
1
-
1
0
0
-
j
]
,
1
2
[
1
0
0
1
-
1
0
0
j
]
,
1
2
[
1
0
0
1
j
0
0
1
]
,
and
1
2
[
1
0
0
1
j
0
0
-
1
]
.
4. The method of claim 3 , wherein the first set of precoding matrices further includes
1
2
[
1
0
1
0
]
,
1
2
[
1
0
-
1
0
]
,
1
2
[
1
0
j
0
]
,
1
2
[
1
0
-
j
0
]
,
1
2
[
0
1
0
1
]
,
1
2
[
0
1
0
-
1
]
,
1
2
[
0
1
0
j
]
,
1
2
[
0
1
0
-
j
]
.
5. The method of claim 1 , further comprising:
initially recommending the first or second set of precoding matrices by indicating to the base station the first or second transmission coherence as a coherence capability of the UE.
6. The method of claim 1 , further comprising:
transmitting data over two or more antenna ports according to a precoding matrix indicated by a precoding matrix indicator contained in the precoding matrix indication field.
7. A method implemented by a base station in a wireless communication network of indicating to a user equipment (UE), a precoding matrix for an uplink transmission from the UE to the base station, said method comprising:
transmitting a control message to the UE, said control message including a precoding matrix indication field configurable to at least a first and second configuration,
wherein:
the first configuration of the precoding matrix indication field identifies precoding matrices in both a first set and a second set of precoding matrices, where the first and second set of precoding matrices correspond to a requirement for a first and second transmission coherence of the UE, respectively;
the second configuration of the precoding matrix indication field identifies precoding matrices in the second set of precoding matrices, but not the first set of precoding matrices;
the precoding matrix indication field is further configurable to a third configuration;
the third configuration of the precoding matrix indication field identifies precoding matrices in a third set of precoding matrices, in addition to the first and second sets of precoding matrices, the third set of precoding matrices corresponding to a requirement for a third transmission coherence of the UE; and
for maximum of four spatial layers, the first, second and third configurations of the precoding matrix indication field occupy 5 , 4 and 6 information bits, respectively.
8. The method of claim 7 , wherein the first, second and third transmission coherence represent partial coherence, non-coherence and full coherence, respectively.
9. The method of claim 7 , wherein the first transmission coherence represents partial coherence and the first set of precoding matrices includes
1
2
[
1
0
0
1
1
0
0
-
j
]
,
1
2
[
1
0
0
1
1
0
0
j
]
,
1
2
[
1
0
0
1
-
j
0
0
1
]
,
1
2
[
1
0
0
1
-
j
0
0
-
1
]
,
1
2
[
1
0
0
1
-
1
0
0
-
j
]
,
1
2
[
1
0
0
1
-
1
0
0
j
]
,
1
2
[
1
0
0
1
j
0
0
1
]
,
and
1
2
[
1
0
0
1
j
0
0
-
1
]
.
10. The method of claim 9 , wherein the first set of precoding matrices further includes
1
2
[
1
0
1
0
]
,
1
2
[
1
0
-
1
0
]
,
1
2
[
1
0
j
0
]
,
1
2
[
1
0
-
j
0
]
,
1
2
[
0
1
0
1
]
,
1
2
[
0
1
0
-
1
]
,
1
2
[
0
1
0
j
]
,
and
1
2
[
0
1
0
-
j
]
.
11. A user equipment (UE) operable in a wireless communication network, said UE being configured to transmit over multiple antenna ports, said UE comprising:
an interface circuit; and
a processing circuit configured to cause the UE to:
receive a control message from a base station including a precoding matrix indication field configurable to at least a first and second configuration,
wherein:
the first configuration of the precoding matrix indication field identifies precoding matrices in both a first set and a second set of precoding matrices, where the first and second sets of precoding matrices correspond to a requirement for a first and second transmission coherence of the UE, respectively;
the second configuration of the precoding matrix indication field identifies precoding matrices in the second set of precoding matrices, but not the first set of precoding matrices
the precoding matrix indication field is further configurable to a third configuration;
the third configuration of the precoding matrix indication field identifies precoding matrices in a third set of precoding matrices, in addition to the first and second sets of precoding matrices, the third set of precoding matrices corresponding to a requirement for a third transmission coherence of the UE; and
for maximum of four spatial layers, the first, second and third configurations of the precoding matrix indication field occupy 5 , 4 and 6 information bits, respectively.
12. The UE of claim 11 , wherein the first, second and third transmission coherence represent partial coherence, non-coherence and full coherence, respectively.
13. The UE of claim 11 , wherein the first transmission coherence represents partial coherence and the first set of orecodina matrices includes
1
2
[
1
0
0
1
1
0
0
-
j
]
,
1
2
[
1
0
0
1
1
0
0
j
]
,
1
2
[
1
0
0
1
-
j
0
0
1
]
,
1
2
[
1
0
0
1
-
j
0
0
-
1
]
,
1
2
[
1
0
0
1
-
1
0
0
-
j
]
,
1
2
[
1
0
0
1
-
1
0
0
j
]
,
1
2
[
1
0
0
1
j
0
0
1
]
,
and
1
2
[
1
0
0
1
j
0
0
-
1
]
.
14. The UE of claim 13 , wherein the first set of precoding matrices further includes
1
2
[
1
0
1
0
]
,
1
2
[
1
0
-
1
0
]
,
1
2
[
1
0
j
0
]
,
1
2
[
1
0
-
j
0
]
,
1
2
[
0
1
0
1
]
,
1
2
[
0
1
0
-
1
]
,
1
2
[
0
1
0
j
]
,
and
1
2
[
0
1
0
-
j
]
.
15. The UE of claim 11 , wherein the processing circuit is further configured to cause the UE to:
initially recommend the first or second set of precoding matrices by indicating to the base station the first or second transmission coherence as a coherence capability of the UE.
16. The UE of claim 11 , wherein the processing circuit is further configured to cause the UE to:
transmit data over two or more antenna ports according to a precoding matrix indicated by a precoding matrix indicator contained in the precoding matrix indication field.
17. A base station operable in a wireless communication network, said base station comprising:
an interface circuit; and
a processing circuit configured to cause the base station to:
transmit a control message to a user equipment (UE), said control message including a precoding matrix indication field configurable to at least a first and second configuration;
wherein:
the first configuration of the precoding matrix indication field identifies precoding matrices in both a first set and a second set of precoding matrices, where the first and second set of precoding matrices correspond to a requirement for a first and second transmission coherence of the UE, respectively;
the second configuration of the precoding matrix indication field identifies precoding matrices in the second set of precoding matrices, but not the first set of precoding matrices;
the precoding matrix indication field is further configurable to a third configuration;
the third configuration of the precoding matrix indication field identifies precoding matrices in a third set of precoding matrices, in addition to the first and second sets of precoding matrices, the third set of precoding matrices corresponding to a requirement for a third transmission coherence of the UE; and
for maximum of four spatial layers, the first, second and third configurations of the precoding matrix indication field occupy 5 , 4 and 6 information bits, respectively.
18. The base station of claim 17 , wherein the first, second and third transmission coherence represent partial coherence, non-coherence and full coherence, respectively.
19. The base station of claim 17 , wherein the first transmission coherence represents partial coherence and the first set of precoding matrices includes
1
2
[
1
0
0
1
1
0
0
-
j
]
,
1
2
[
1
0
0
1
1
0
0
j
]
,
1
2
[
1
0
0
1
-
j
0
0
1
]
,
1
2
[
1
0
0
1
-
j
0
0
-
1
]
,
1
2
[
1
0
0
1
-
1
0
0
-
j
]
,
1
2
[
1
0
0
1
-
1
0
0
j
]
,
1
2
[
1
0
0
1
j
0
0
1
]
,
and
1
2
[
1
0
0
1
j
0
0
-
1
]
.
20. The base station of claim 17 , wherein the first set of precoding matrices further includes
1
2
[
1
0
1
0
]
,
1
2
[
1
0
-
1
0
]
,
1
2
[
1
0
j
0
]
,
1
2
[
1
0
-
j
0
]
,
1
2
[
0
1
0
1
]
,
1
2
[
0
1
0
-
1
]
,
1
2
[
0
1
0
j
]
,
and
1
2
[
0
1
0
-
j
]
.