IS-95A Rev Ch Repeater/Derepeater (CDMA Reference Blockset)

Repeat or derepeat the symbols of the input frame for the reverse Access and Traffic channels based on the data rate

Library

IS-95A Mobile Station Transmitter

Description

This block repeats or derepeats the symbols of the input frame for the reverse Access and Traffic channels based on the data rate.

In repeater operation mode, the block repeats each input symbol whenever the information rate is lower than full rate. Each symbol is repeated once for half rate, three times for quarter rate, and seven times for eighth rate. This results in the same modulation symbol rate for all data rates.

In derepeater operation mode, the block obtains the symbols by adding together the repetitions of the transmitted symbols.

The size of the input port is equal to the maximum possible size of 576 (Rate Set II, Traffic Full Rate) for the repeater mode of operation. Similarly, the output size is equal to the maximum possible size of 576 (Rate Set II, Traffic Full Rate) for the derepeater mode of operation. Any unused bits in the output are set to zero. The number of relevant input bits for repeater operation mode and relevant output bits for derepeater operation mode are specified in the table below.

Channel Type
Number of Relevant Input Bits (Repeater)
Number of Relevant Output Bits (Derepeater)

Access
288
288

Traffic, Rate Set I, Full Rate
576
576

Traffic, Rate Set I, Half Rate
288
288

Traffic, Rate Set I, Quarter Rate
144
144

Traffic, Rate Set I, Eighth Rate
72
72

Channel Type	Number of Relevant Input Bits (Repeater)	Number of Relevant Output Bits (Derepeater)
Access	288	288
Traffic, Rate Set I, Full Rate	576	576
Traffic, Rate Set I, Half Rate	288	288
Traffic, Rate Set I, Quarter Rate	144	144
Traffic, Rate Set I, Eighth Rate	72	72

Inputs

Rate

Integer scalar that specifies the data rate for the input signal. To indicate a rate fraction of Full, Half, or Quarter, use an input value of 0, 1, or 2, respectively. The table below shows all valid channel types and rate fractions, along with their associated data rates and Rate input values.


Channel Type	Data Rate (bps)	Input Value
Access (always Half rate)	4800	1
Traffic, Rate Set I, Full	9600	0
Traffic, Rate Set I, Half	4800	1
Traffic, Rate Set I, Quarter	2400	2
Traffic, Rate Set II, Full	14400	0
Traffic, Rate Set II, Half	7200	1
Traffic, Rate Set II, Quarter	3600	2

Frame In

Real vector (of binary data for repeater functionality) of size 576 containing the input frame.

Outputs

Real vector (of binary data for repeater functionality) of size 576. It represents the repeated or derepeated output frame, depending on the Function parameter.

Dialog Box

Parameters

Channel type: The channel type, either Access or Traffic.
Function: Repeater or Derepeater.

Specification References

IS-95A 6.1.3.1.4
J-STD-008 2.1.3.1.4

IS-95A Rev Ch Rake Finger IS-95A Rev Ch Short Code Despreader