I want to generate a for loop to inject primary user (PU) signals inside the primary resource blocks (PRBs)

Pls can someone help with generating a for loop for injecting primary user (PU) signals into primary resource blocks (PRBs). The signals are complex In-phase and Quadrature signals (IQ), each used frequency is '1' meaning user is active, and each unused frequency is '0' meaning user is not active or absent. Find the codes below.

%% Parameters

T = 600; % transmit signals

PRB = 6; % Primary Resource Block (PRB)

M = 4; % Modulation

snr = 15; % Noise

%% Select PU activity inside the RF spectrum:

usedFrequencies = [1, 3, 5];

unUsedFrequencies = [2, 4, 6];

%% inject PU signals inside the available PRBs:

for t = 1:1:T