| 摘要 |
A PDSCH resource element mapping method is used for joint transmissions. The method solves a problem of colliding resource elements in joint transmissions, due to interference caused when PDSCH resource elements are transmitted in the resource block of one cell and cell-specific reference signals (CRSs) are transmitted in the same location of the resource block of an adjacent cell. The method is particularly beneficial for coordinated multipoint (CoMP) transmissions. The PDSCH resource element mapping method employs one of three schemes for transmitting the collided resource elements, with minimal interference. In the first scheme, one PDSCH symbol is transmitted over three consecutive CRS-collided PDSCH resource elements. In the second scheme, two PDSCH symbols are transmitted over three consecutive CRS-collided PDSCH resource elements. In a third scheme, CRS-collided resource elements are transmitted using a lower modulation order than is specified by the modulation and coding scheme. |
| 主权项 |
1. A method comprising:
receiving, by a user equipment (UE) in a cluster, a joint transmission comprising a plurality of resource blocks (RBs) from multiple respective base stations (eNBs) in the cluster, each RB comprising a plurality of physical downlink shared channel (PDSCH) resource elements (REs), wherein:
a first eNB transmits a first RB of the at least two RBs, the first transmission comprising:
a cell-specific reference signal (CRS) at a first RE location of the first RB, wherein the first RE location comprises a subcarrier and symbol period of the RB; anda linear combination of multiple symbols at a second location of the first RB, wherein the first and second RE locations occupy the same symbol period of the RB;a second eNB transmits a second RB of the plurality of RBs, the second transmission comprising:
a second CRS at the second RE location of the second RB; anda linear combination of the multiple symbols at the first location of the second RB; extracting, by the UE, a linear combination of the multiple symbols from the joint transmission; detecting, by the UE, the first CRS from the first RB, wherein the UE employs the first CRS to estimate a first channel response of a first channel disposed between the UE and the first eNB; detecting, by the UE, the second CRS from the second RB, wherein the UE employs the second CRS to estimate a second channel response of a second channel disposed between the UE and the second eNB; and detecting, by the UE, a third CRS from a third RB, wherein the UE employs the third CRS to estimate a third channel response of a third channel disposed between the UE and a third eNB; multiplying, by the UE, the first channel response by the first CRS, resulting in a first reconstructed CRS; multiplying, by the UE, the second channel response by the second CRS, resulting in a second reconstructed CRS; and multiplying, by the UE, the third channel response by the third CRS, resulting in the third reconstructed CRS. |
