How can I change it from BPSK to QPSK?

I have identified a relevant example code document at this link : https://uk.mathworks.com/help/phased/ug/improve-snr-and-capacity-of-wireless-communication-using-antenna-arrays.html?searchHighlight=ULA%20MIMO&s_tid=srchtitle_support_results_24_ULA%2520MIMO

However, it mentions a SISO system with the signal at BPSK. how can I change it from BPSK to QPSK as I am struggling to see where the BPSK section is as there is no pskmod or demod function within the code available.

Any Help would be appreciated

Answer 1

[Ganapathi Subramanian R]

Hi Liam,

I understand that you are working with 'Improve SNR and Capacity of Wireless Communication Using Antenna Arrays' example and would like to know how BPSK modulation is implemented in that example. Kindly follow the below steps to visualize the BPSK implementation.

1) Execute the following command in MATLAB command window to open the above example.

>> openExample('phased/ArrayProcessingForMIMOExample')

2) Under the 'Current Folder' tab in MATLAB, open the 'helperMIMOBER.m' file.

3) This MATLAB script computes the Bit Error Rate(BER) for BPSK modulation. This script contains the implementation of BPSK modulation.

Note : Kindly modify the the above MATLAB script to convert BPSK modulation into QPSK modulation.

[Liam]

I have opened this, however, I am still unsure as to how the BPSK is coded. The function is that of xt = 1/sqrt(Ntx)*(2*x-1)*wt

How is this mapping to BPSK?