where is the wrong this code!

where is the wrong in this code.i can't run this code

clear; clc;

% Modulation schemes to compare
modulations = {'BPSK', 'QPSK', '8-PSK', '16-QAM', '64-QAM'};

% Transmit power and data rate
P_t = 0.1; % W
R = 100e6; % bps

% Extinction coefficient
c = 0.15; % m^-1

% PIN PD parameters
eta = 0.82;
fc = 300e6; % Hz

% Rx parameters
d = 0.2; % m
f = 0.25; % m
fov = 0.69;

% BER calculation
for i = 1:length(modulations)
    modulation = modulations{i};
    % Assume ideal receiver for simplicity
    [~, ber(i)] = berawgn(modulation, R, P_t);
end

Error using berawgn
EbNo must be a real vector.

% Plot BER results
semilogy(1:length(modulations), ber, '-o');
xlabel('Modulation');
ylabel('BER');
xticks(1:length(modulations));
xticklabels(modulations);
grid on;

Answer 1

[Cris LaPierre]

The first input to berawgn must be a scalar or vector. Your first input is a character vector that seems to what is expected as the second input (modtype).

ber = berawgn(EbNo,modtype,M)

The first input argument, EbNo, is the ratio of bit energy to noise power spectral density in dB (Eb/N0).

Consult the documentation to be sure you are supplying the inputs the function expects.