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comm.DifferentialEncoder System object

Package: comm

Encode binary signal using differential coding


The DifferentialEncoder object encodes the binary input signal within a channel. The output is the logical difference between the current input element and the previous output element.

To encode a binary signal using differential coding:

  1. Define and set up your differential encoder object. See Construction.

  2. Call step to encode a binary signal according to the properties of comm.DifferentialEncoder. The behavior of step is specific to each object in the toolbox.

    Note:   Starting in R2016b, instead of using the step method to perform the operation defined by the System object™, you can call the object with arguments, as if it were a function. For example, y = step(obj,x) and y = obj(x) perform equivalent operations.


H = comm.DifferentialEncoder creates a differential encoder System object, H. This object encodes a binary input signal by calculating its logical difference with the previously encoded data.

H = comm.DifferentialEncoder(Name,Value) creates object, H, with each specified property set to the specified value. You can specify additional name-value pair arguments in any order as (Name1,Value1,...,NameN,ValueN).



Initial value used to generate initial output

Specify the initial condition as a real scalar. This property can have a logical, numeric, or fixed-point ( object) data type. The default is 0. The object treats nonbinary values as binary signals.


cloneCreate differential encoder object with same property values
getNumInputsNumber of expected inputs to step method
getNumOutputsNumber of outputs from step method
isLockedLocked status for input attributes and nontunable properties
releaseAllow property value and input characteristics changes
resetReset states of differential encoder object
stepEncode binary signal using differential coding


expand all

Create a differential encoder object.

diffEnc = comm.DifferentialEncoder;

Generate random binary data. Encode the data.

data = randi([0 1],10,1);
encData = diffEnc(data)
encData =



This object implements the algorithm, inputs, and outputs described on the Differential Encoder block reference page. The object properties correspond to the block parameters, except:

The object only supports single channel, column vector inputs.

Introduced in R2012a

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