e Block Channel Channel Channel d(6) d(i) ,d(s) ..., Concatenation Coding Coding Coding Rate Matching fof1,...,FG-1 Data and Control Multiplexing Code Block Concatenation Channel Interleaver Codewords Transport Block Processing for DL-SCH, PCH and MCH UL-SCH Transport Block Processing FIGURE 9-68 Downlink/uplink transport block processing [107] A tail-biting convolutional code with constraint length 7 and coding rate 1/3 is used in 3GPP LTE. The turbo encoder used in 3GPP LTE is a Parallel Concatenated Convolutional Code (PCCC) with two 8-state constituent encoders and one turbo code internal interleaver. The minimum coding rate of the turbo encoder is 1/3. Trellis termination is performed by taking the tail bits from the shift register feedback after all information bits are encoded. Tail bits are padded after the encoding of information bits. The rate matching for turbo coded transport channels is defined per coded block and consists of interleaving of the three information bit streams d(1) and d(2) followed by the collection of bits and the generation of a circular buffer, as depicted in Figure 9-69. The output bits for each code block are transmitted as described in the next section. The rate matching output bit sequence is denoted as eksk=0,...,E - 1 where E denotes the rate matching output sequence length. The input bit sequence 9.15 3GPP LTE physical layer protocols Table 9-19 Coding Schemes for Various Channel Types [107] Channel Types Channel Types Coding Scheme Coding Rate Traffic Channels Uplink Shared Channel (UL-SCH) Turbo Coding Downlink Shared Channel (DL-SCH) Paging Channel (PCH) Multicast Channel (MCH) Broadcast Channel (BCH) Tail-Biting Convolutional Coding Control Channels Downlink Control Information (DCI) Tail-Biting Convolutional Coding Control Format Indicator (CFI) Block Code HARQ Indicator (HI) Repetition Code Uplink Control Information (UCI) Block Code Variable Tail-Biting Convolutional Coding Sub-block Interleaver Virtual Circular Buffer Sub-block Bit Selection Interleaver Collection an