Computing Channel Power from file containing RMS measurements from tri-axial spectrum analyzer

Question

I have some files from a spectrum analyzer in RMS mode equipped with a tri-axial antenna. I am supposed to compute the channel power evolution for two distinct LTE channels.

I have files containing the various measures which I parse and upload in MATLAB.

I was using this function to compute the channel power but I'm not 100% sure it is the correct method

    % Compute the power of a signal within the specified frequency range
function power = ChannelPower(signal, FreqStart, FreqStop, FreqStep)

    
    % Create a frequency vector
    frequencyAx = FreqStart:FreqStep:FreqStop;
    
    % Find the indexes corresponding to FreqStart and FreqStop
    indexStart = find(frequencyAx >= FreqStart, 1);
    indexStop = find(frequencyAx <= FreqStop, 1, 'last');
    
    % Take the signal and extract the relevant portion
    signalInRange = signal(indexStart:indexStop);


    power = sum(abs(signalInRange)*FreqStep); %height*base (rectangular approximation?)

I'm quite confused about computing the channel power starting from frequency measurements in RMS mode, so any help would be very appreciated. Can I use the bandpower MATLAB function to achieve similar results?

Furthermore, I was computing the channel power using this vector

total_field_per_measurement = (sum(signals.^2, 3));

which is the squared sum of the signals acquired along the three axes of my tri-axial antenna.