5.3.3A Precoding

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The precoder takes as input a block of vectors , from the transform precoder and generates a block of vectors , to be mapped onto resource elements.

5.3.3A.1 Precoding for transmission on a single antenna port

For transmission on a single antenna port, precoding is defined by

where , .

5.3.3A.2 Precoding for spatial multiplexing

Precoding for spatial multiplexing is only used in combination with layer mapping for spatial multiplexing as described in clause 5.3.2A.2. Spatial multiplexing supports or antenna ports where the set of antenna ports used for spatial multiplexing is and , respectively.

Precoding for spatial multiplexing is defined by

where , .

The precoding matrix of size is given by one of the entries in Table 5.3.3A.2-1 for and by Tables 5.3.3A.2-2 through 5.3.3A.2-5 for where the entries in each row are ordered from left to right in increasing order of codebook indices.

Table 5.3.3A.2-1: Codebook for transmission on antenna ports

Codebook index	Number of layers
0
1		–
2		–
3		–
4		–
5		–

Table 5.3.3A.2-2: Codebook for transmission on antenna ports with

Codebook index	Number of layers
0 – 7
8 – 15
16 – 23

Table 5.3.3A.2-3: Codebook for transmission on antenna ports with

Codebook index	Number of layers
0 – 3
4 – 7
8 – 11
12 – 15

Table 5.3.3A.2-4: Codebook for transmission on antenna ports with

Codebook index	Number of layers
0 – 3
4 – 7
8 – 11

Table 5.3.3A.2-5: Codebook for transmission on antenna ports with

Codebook index	Number of layers
0