3.2 Normalized and relative power

Usually in TMAA, the radiation pattern is synthesized at center frequency by suppressing the sideband radiation level to sufficiently low value. Thus, the maximum of the power radiated at f0 is used to normalize the corresponding power pattern at center frequency. On the other hand, the sideband power is divided by the maximum power at f0 to measure the relative power level at different sidebands with respect to that of the radiation at center frequency. In this regard, the relative signal power radiated at different harmonics (k 6¼ 0) is measured as in Eq. (12):

$$\text{SBL}\_k(\text{dB}) = \text{20} \ast \log\_{10}(AF\_k(\theta, t) / \max \left(AF\_0(\theta, t)\right)) \tag{12}$$

where "SBLk" represents the relative value of sideband level at kth harmonic (k = 1, 2, … ), i.e., relative value of the array factor AFk in dB, and "max (AF0 (θ, t))" is the maximum value of the array factor at operating frequency ω0, i.e., the maximum radiation level at k=0. Thus, with k=0, Eq. (11) gives the normalized power pattern for the center frequency pattern, whereas, for the sideband radiations (with k ¼6 0), it is the relative power with respect to the maximum of the center frequency pattern.
