MATLAB: Error when running Pluto Radio QPSK Example

adalm-plutoCommunications Toolboxexampleplutoqpskreceivertransmitter

Recently I have been attempting to run the 'QPSK Transmitter with ADALM-PLUTO Radio' and 'QPSK Receiver with ADALM-PLUTO Radio' example in MATLAB R2020b, however I have been encountering the following error:
'QPSKDataDecoder' is used in QPSK Transmitter and Receiver
Error in QPSKReceiver/setupImpl (line 113)
obj.pDataDecod = QPSKDataDecoder(...
Error in runPlutoradioQPSKReceiver (line 56)
[~, ~, ~, BER] = rx(rcvdSignal):
Error in RX (line 5)
BER = runPlutoradioQPSKReceiver(prmQPSKReceiver, printReceivedData);
I have attached links to these examples for reference:
Transmitter Example:
https://www.mathworks.com/help/releases/R2020b/supportpkg/plutoradio/ug/qpsk-transmitter-with-adalm-pluto-radio-1.html
Receiver Example:
https://www.mathworks.com/help/releases/R2020b/supportpkg/plutoradio/ug/qpsk-receiver-with-adalm-pluto-radio.html
Why is this error occurring and how can it be resolved?

Best Answer

The 'plutoradioQPSKReceiverExample' throws the error:
 'QPSKDataDecoder' is used in QPSK Transmitter and Receiver
due to a missing file 'QPSKDataDecoder' in the Support Package path. Both the 'plutoradioQPSKReceiverExample' in Pluto Hardware Support and 'QPSKTransmitterAndReceiverExample' in Communications Toolbox use a common file 'QPSKDataDecoder' that is missing in the support package directory, and returns this error as a result.
To resolve this issue:
Click on the link "QPSK Transmitter and Receiver" in the error message 
'QPSKDataDecoder' is used in QPSK Transmitter and Receiver
The current folder path will then be changed to the 'QPSKTransmitterAndReceiverExample' directory in the Communications Toolbox, in which 'QPSKDataDecoder' is available,
Next, execute:
>>addpath(pwd)
at the MATLAB Command Window to add this location to the MATLAB path. After doing so, 'plutoradioQPSKReceiverExample' and 'QPSKTransmitterandReceiverExample' will run successfully.
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