4.12 Coding for E-RUCCH

25.2223GPPMultiplexing and channel coding (TDD)Release 17TS

For 1.28Mcps TDD, E-RUCCH supports both a 5ms and a 10ms TTI. For 3.84Mcps and 7.68Mcps TDD, E-RUCCH supports a TTI of 10ms only. The sequence of 39 information bits to be transmitted on one E-RUCCH as supplied by higher layers is defined as bits .

The following processing steps (in sequential order) are defined for E-RUCCH:

– CRC attachment

– Channel coding

– Rate matching

– Bit scrambling

– Frame related 2^nd interleaving

– Mapping to physical channels

4.12.1 CRC attachment for E-RUCCH

From the sequence of A_i=39 bits () a CRC of length L_i=16 is appended according to Section 4.2.1.1. The bits output from CRC attachment are denoted b_im,k, where k=1,2,3, … A_i+L_i and A_i = 39

For 3.84Mcps and 7.68Mcps TDD, each parity bit b_im,k , (where k=A_i+1,A_i+2, … A_i+L_i) is then XOR’d with 1 such that its polarity is reversed.

4.12.2 Channel coding for E-RUCCH

1/3 rate convolutional channel coding is applied to the sequence b₁, b₂, …, b_im,k in accordance with section 4.2.3.1, resulting in the sequence of bits z₁, z₂, …, z_3(k+8).

4.12.3 Rate matching for E-RUCCH

Rate matching for E-RUCCH shall be applied to the input sequence z₁, z₂, …, z_3(k+8) to obtain the output sequence r₁, r₂, …, r_U, where U = 176 for 1.28Mcps and U= 232 for 3.84Mcps and 7.68Mcps TDD, according to the general method described in subclause 4.2.7.

4.12.4 Bit scrambling for E-RUCCH

Bit scrambling for E-RUCCH shall be performed in accordance with the general method described in subclause 4.2.9.

4.12.5 Interleaving for E-RUCCH

Frame-related 2^nd interleaving for E-RUCCH shall be performed in accordance with the general method described in subclause 4.2.11.1.

4.12.6 Physical channel mapping for E-RUCCH

Physical channel mapping for the E-RUCCH shall be performed in accordance with the general method described in subclause 4.2.12.1.