CDMA Reference Blockset | ![]() ![]() |
Repeat, puncturing if necessary, or derepeat the symbols of the encoded frame
Library
IS-95 Base Station Transmitter
Description
This block repeats or derepeats the convolutionally encoded frame symbols for the forward channel. While repeating, the block also punctures the data if necessary.
For the Paging and Traffic channels and in repeater operation mode, this block repeats the convolutionally encoded symbols prior to block interleaving whenever the information rate is lower than full rate. In the half rate, quarter and one-eighth data rate modes of operation, each symbol repeats once, three and seven times, respectively. In Rate Set I, the repetition operation results in a frame size of 384 symbols for all data rates. For Rate Set II, the repetition operation results in a frame size of 576 symbols for all data rates, but the repeated data is punctured before leaving the output port. The puncturing pattern deletes the third symbol in a group of three symbols while retaining the first and the second symbols. After puncturing, the output frame size is 384 symbols.
For the Sync channel in repeater operation mode, the block repeats each symbol once. Therefore, each output frame consists of 128 symbols.
The derepeater inserts zeros in the positions of the punctured symbols and averages over the repeated data symbols.
For repeater operation mode, the input and output frame sizes equal 576 and 384, respectively, in Paging and Traffic channels. For the Sync channel, the input frame size is 576 and the output frame size is 128.
For derepeater operation mode, the output port size is the maximum possible size of 576 (Rate Set II, Traffic Full Rate). The following table shows the number of relevant bits at the input of the repeater and output of the derepeater, for each channel type and data rate.
Inputs
Outputs
For repeater operation mode, this is a binary vector of size 384 (128 for the Sync channel) representing the output frame. For derepeater operation mode, this is a real vector of size 576.
Dialog Box
Parameters
See Also
IS-95A Rev Ch Repeater/Derepeater
IS-95A Forward Traffic Channel Codec Demo
Specification References
IS-95A 7.1.3.1.4
J-STD-008 3.1.3.1.4
![]() | IS-95A Fwd Ch Rake Finger | IS-95A Fwd Ch Scrambler | ![]() |