Communications Blockset™

Differential Decoder - Decode binary signal using differential coding

Library

Source Coding

Description

The Differential Decoder block decodes the binary input signal. The output is the logical difference between the present input and the previous input. More specifically, the block's input and output are related by

m(t₀) = d(t₀) XOR Initial condition parameter value

m(t_k) = d(t_k) XOR d(t_k-1)

where

• d is the differentially encoded input.

• m is the output message.

• t_k is the kth time step.

• XOR is the logical exclusive-or operator.

The input can be either a scalar, a vector, or a frame-based matrix. This block processes each vector element independently.

Dialog Box

Initial condition

The logical exclusive-or of this value with the initial input value forms the initial output value.

References

[1] Couch, Leon W., II, Digital and Analog Communication Systems, Sixth edition, Upper Saddle River, N. J., Prentice Hall, 2001.

Pair Block

Differential Encoder

Descrambler

Differential Encoder