Application of a Channel Estimation Algorithm to Spectrum Sensing in a Cognitive Radio Context

Algorithm 1

Application of the MMSE-based algorithm to free band detection.

begin

  Initialization: 𝐑^LS_𝐻, 𝑒_𝜎>0, 𝜎²_(𝑖=0) and 𝜍;

 𝑖←1;

 while 𝜎²_(𝑖)−𝜎²_()𝑖−1>𝑒_𝜎 do

  if  𝑖=1 then

    Perform LMMSE channel estimation;

    Perform the noise variance estimation;

    Calculate the matrix 𝐑^LMMSE_𝐻;

  else

    Perform an LMMSE channel estimation with 𝐑^LMMSE_𝐻;

    Perform the noise variance estimation;

  end

  𝑖←𝑖+1;

 end

 Calculate the metric ℳ;

 if ℳ<𝜍 then

    return  ℍ₀;

 else

    return  ℍ₁;

 end

end