5.4.2B PUCCH format 4
36.2113GPPEvolved Universal Terrestrial Radio Access (E-UTRA)Physical channels and modulationRelease 17TS
The block of bits 
shall be scrambled with a UE-specific scrambling sequence, resulting in a block of scrambled bits 
according to
where the scrambling sequence 
is given by clause 7.2. The scrambling sequence generator shall be initialised with 
at the start of each subframe where 
is the C-RNTI.
The block of scrambled bits 
shall be QPSK modulated as described in Clause 7.1, resulting in a block of complex-valued modulation symbols 
where 
.
The block of complex-valued symbols 
is divided into 
sets, each corresponding to one SC-FDMA symbol. Transform precoding shall be applied according to
where 
, 
and 
are given by Table 5.4.2C-1 for normal PUCCH format 4 and shortened PUCCH format 4, resulting in a block of complex-valued symbols 
. The variable
, where 
represents the bandwidth of the PUCCH format 4 in terms of resource blocks, shall fulfil
where 
is a set of non-negative integers.