In time modulated array (TMA), harmonic radiations, which causes a decrease in efficiency, occurs in multiples of the modulation frequency in addition to the main radiation due to the implementation of RF switches. In this study, a new sinusoidal beamforming method is proposed for the desired pattern only at required harmonic frequencies. Furthermore, the number of excitation functions has been significantly reduced with the help of the proposed thinned array architecture. Compared to existing beamforming methods with TMA, the proposed method has the ability to generate independent beam only at the desired harmonic frequency. The effectiveness of the proposed method is shown in the example scenario.